Sources and Techniques in Boat Archaeology: Papers based on those presented to a Symposium at Greenwich in September 1976, together with edited discussion 9780904531824, 9781407345673
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Table of contents :
Front Cover
Copyright
Table of Contents
LIST OF ILLUSTRATIONS
EDITOR'S INTRODUCTION
LIST OF CONTRIBUTORS
1. INTRODUCTORY ADDRESS
2. SETTING THE SCENE
3. A GLOSSARY OF BOAT ARCHAEOLOGY TERMS
4. DEGRADATION OF WOOD
5. CONSERVATION OF OLD WATER-LOGGED WOOD
6. ASPECTS OF WATERLOGGED WOOD CONSERVATION
7. NEW POSSIBILITIES IN CHEMICAL ENGINEERING FOR CONSERVING STRUCTURES OF WATERLOGGED WOOD
8. ETHNOGRAPHY AND LIVING TRADITION
9. THE XAVEGA BOAT A CASE STUDY IN THE INTEGRATION OF ARCHAEOLOGICAL AND ETHNOLOGICAL DATA
10. SEARCHING FOR PATTERN AMONG THE LOGBOATS OF ENGLAND AND WALES
11. QUANTITATIVE METHODS AND BOAT ARCHAEOLOGY
12. SOME PRINCIPLES FOR THE RECORDING AND PRESENTATION OF ANCIENT BOAT STRUCTURES
13. THE RECORDING AND PRESENTATION OF FINDS FROM NAUTICAL CONTEXTS
14. RECORDING THE REMAINS OF A SEWN BOAT FOUND AT SKEPPARGATAN 4 IN STOCKHOLM
15. HYPOTHETICAL RECONSTRUCTIONS IN BOAT ARCHAEOLOGY
16. HYPOTHETICAL RECONSTRUCTIONS AND THE NAVAL ARCHITECT
17. EXPERIMENTAL ARCHAEOLOGY THEORY AND PRINCIPLES
18. ASPECTS OF EXPERIMENTAL BOAT ARCHAEOLOGY
19. PRELIMINARY REPORT ON THE BRENDAN PROJECT
20. ANCIENT BOATBUILDING -- A PROVISIONAL CLASSIFICATION
21. CELTIC SHIPS OF EUROPE
22. BOAT-ARCHAEOLOGY OF THE THAMES
23. SUMMARY AND CONCLUDING REMARKS
GLOSSARY
Citation preview
Sources and Techniques in Boat Archaeology Papers based on those presented to a Symposium at Greenwich in September I 976, together with edited discussion edited by Sean_ McGrail
National Maritime Museum, Greenwich, Archaeological Series No. 1
BAR Supplementary Series 2 9 1 977
British Archaeological Reports 122, Banbury Road, Oxford OX2 7BP, England
GENERAL EDITORS A. C. C. Brodribb, M.A. Mrs. Y. M. Hands
A. R. Hands, B.Sc., M.A., D.Phil. D. R. Walker, M.A.
B.A.R. Supplementary Series 29, 1977: "Sources and Techniques in Boat Archaeology" ©
Th� individual authors and the National Maritime Museum, Greenwich, 1977
The authors’ moral rights under the 1988 UK Copyright, Designs and Patents Act are hereby expressly asserted. All rights reserved. No part of this work may be copied, reproduced, stored, sold, distributed, scanned, saved in any form of digital format or transmitted in any form digitally, without the written permission of the Publisher. ISBN 9780904531824 paperback ISBN 9781407345673 e-book DOI https://doi.org/10.30861/9780904531824 A catalogue record for this book is available from the British Library This book is available at www.barpublishing.com
CONTENTS Page List of Illustrations
(iv)
Editor's Introduction
(ix)
List of Contributors
(xi)
INTRODUCTION David Wilson
1: Introductory Address
1
E. V. Wright
2:
3
Setting the Scene
GWSSARY OF TERMS J. E • G. McKee
3: A Glossary of Boat Archaeology Terms
Discussion - Chaired by Basil Greenhill, National Maritime Museum
9
14
WOOD DEGRADATION AND CONSERVATION
15
J. F. Levy
4: Degradation of Wood
J. de Jong
5: Conservation of Old Waterlogged Wood
23
C. ·W. Gregson
6: Aspects of Waterlogged Wood Conservation
-±5
J. Roelf zema
7: New Possibilities in Chemical Engineering for Conserving Structures of Waterlogged Wood
55
Discussion - Chaired by Andrew Oddy, British Museum Research Laboratory ETHNOGRAPHY AND LlVING TRADITION ( 0 lof Hasrnf Octavio Lixa Filgueiras
60
8: Ethnography and Living Tradition
65
9:
77
The Xavega Boat - a case study in the integration of archaeological and ethnological data
Discussion - Chaired by Sean McGrail, National Maritime Museum
112
QUANTITATIVE TECHNIQUES Sean McGrail
10: Searching for Pattern among the Logboats of England and Wales
115
P age J . M. Graha m
1 1:
Quan t ita t ive Me thods a nd Boa t
1 37
Archaeo logy D iscuss ion - Cha ired b y Ruper t Bruce- M it ford , T he Br it ish Museu m
1 56
RECORD ING F INDS AND PRESENT ING I NFOR MAT ION O le Cru m l in-Pedersen
1 2 :
S o me Pr inc ip les f or t he Record ing
1 63
a nd Presen ta t ion o f Anc ien t Boa t S tructures Ange la Care Evans
1 3 : Record ing a nd P resen tat ion o f F inds f ro m Naut ica l C on tex ts
1 79
Car l O lof Ceder lund
1 4 :
1 91
Record ing t he r e ma ins o f as ewn s h ip f ound a t S kepparga tan 4 i n S tockho lm
D iscuss ion - Cha ired b y Co l in Mar t in, Un ivers i ty o f S t. Andrews
2 01
HYPOTHET ICAL RECONSTRUCT ION OF BOAT F INDS J . E . G . McKee
1 5 :
Hypothet ica l Recons truct ions i n
2 05
Boa t Archaeo logy J . F . Coa tes
1 6 :
Hypothet ica l Reconstruct ions a nd
2 15
t he N ava l Arch itec t D iscuss ion - Cha ired b y Ewan Cor let t, Na t iona l Mar it i me Museu m
2 27
EXPER I MENTAL ARCHAEOLOGY J . M. Co les
1 7 :
Exper i men ta l Archaeo logy -
2 33
t heory a nd p r inc ip les S ean McGra il
1 8 :
Aspects o f Exper i men ta l Boa t
2 45
Archaeo logy T i mo thy S ever in
1 9 :
Pre l im inary Repor t o n t he
2 59
Brendan Pro jec t D iscuss ion - Cha ired b y S verre Marstrander , . Un ivers itetets O ldsaksa m l ing , Os lo
2 66
ANCIENT BOATBU ILD ING Arne Em i l Chr is tensen
2 0 :
Anc ien t Boa tbu i ld ing - a p rov is iona l
2 69
c lass if ica t ion P eter Marsden
2 1:
C elt ic S h ips o f Europe
2 81
Dav id S turdy
2 2 :
Boa t A rchaeo logy o f t he Tha mes
2 89
D iscuss ion - Cha ired b y Det lev E l l mers, D eutsches S ch if fahr tsmuseu m , Bre merhaven
2 98
P age CONCLUS ION Bas i l Greenh i l l D iscuss ion G lossary
2 3 :
S u m mary a nd Conc lud ing Re marks
Cha ired b y Dav id W i lson , T he Br it ish Museu m
3 03 3 07 3 11
L IST OF I LLUSTRAT IONS
F igure 4 .1
P age S cann ing e lec tron micrograph o f Oak ( Quercus s p. )
1 6
s howing t he wood c u t i n t he t ransverse , t angen t ia l l ong i tud ina l a nd r adia l l ong i tudina l p lanes ( x 1 00 ) . 4 .2
S . E. M. p ic ture o f S co ts P ine ( P inus s y lvestr is)
1 6
s how ing t he wood c u t i n t he t ransverse , t angen t ia l l ong it udina l a nd r adia l l ong i tudina l p lanes ( x 9 0 ). 4 .3
S .E . M. p ic ture o f S cots P ine ( Pinus s y lvestris) ,
1 9
s howing t he wood c u t i n t he t ransverse p lane . 5 .1
The L ake I Jsse l l and r ec la ma t ion a nd d eve lop men t
2 4
p ro ject . 5 .2
T he l oca t ion o f t he s h ipwrecks f ound i n t he L ake
2 4
I Jsse l a rea . 5 .3
T he t hree ma in a xes i n wood a nd t he d a mage d ue t o
2 7
s hr inkage a f ter d ry ing a p iece o f o ld wa ter logged wood 5 .4
T he d istr ibu t ion o f PEG 4 000 p erpend icu lar t o t he
2 7
l ong i tudina l d irec t ion i n ap iece o f E uropean o ak . 5 .5
Graph s howing t he d i f ference i n impregna t ion a nd h ence
3 4
c onserva t ion f or o b jects o f t he s a me wood s pec ies a nd q ua li ty b u t o f d i f feren t s ize . 5 .
T he wreck o f a1 9 th c en tury s h ip , f ound n ear L e lystad.
4 1
5 .7
Two r igg ing b locks made o f e lm .
4 1
P ieces o f a n o ak t ree , d a t ing f ro m t he 2 nd . c en tury
4 2
5 .8
B .C . i n we t c ond i t ion , a ir d r ied a nd a f ter c onserva tion u sing t he t ba-PEG 4 000 me thod . 7 .1
P r inc ip les o f t he " Vacuu m F oi l C ocoon" wrapp ing
5 7
s yste m w ith h ea ted f ue l c ircu la t ion . 7 .2 7 .3
F low s hee t o f t he p i lo t p lan t .
5 7
T he b oi ling p oin t o f wa ter r e la ted t o a t mospher ic
5 7
p ressure . 5 8
7 .4
T he Vacuu m c ocoon t es t ing i nsta l la t ion .
8 .1
Bu i ld ing a b oa t w i th o ver lapp ing p lanks ( c l inker ) .
7 0-72
8 .2
B oa ts b u i l t w i th smoo th s ides , p lanks j o ined e dge
7 3-74
t o e dge .
i v
F igure 8 .3
Page Ag a leas u nder c onstruc t ion a t Kongsv iken ,
7 5
Bohus län S weden i n 1 938 . 8 .4
T hree t ypes o f h al f- mode l u sed d ur ing t he b u i ld ing
7 6
o f s h ips w i th s ke le ton c onstruc t ion . 9 .1
P or tuga l : t ypes o f c ra f t .
7 8
9 .2
T he r abelo f or t ranspor t ing t he Por t w ine c asks.
7 9
9 .3
T he f la t-bo t to med
r abe lo c onstruct ion s equence.
8 0
9 .4
T he g rea t migra t ions i n Europe : V-V I I c en tur ies.
8 1
9 .5
T he Pövoa l ancha r em inds u s o f t he B re ton s inago t .
8 2
9 .6
T he S aveiro
8 3
9 .7
u sed t o c arry t he x ävega s e ine .
T he s ave iro 's r esse mb lance t o t he s i lver mode l o f
8 4
a n a ncien t U r b oa t . 9 .8
T he me l ice iro s eaweed g a ther ing v esse l .
8 7
9 .9
Ano ther a nc ien t Ur b oa t .
8 7
The S . Mar t inho masse ira a nd t he s har toush o f t he
8 8
9 .10
Euphra tes . 9 .11
The b arca s errana o f t he Mondego r iver a nd a no ther
8 9
Ur mode l . 9 .12
T he t echn ical c onversion t o Medi terranean p a tterns
9 0-91
o bserved amongst t he Ma 'dan b oa tbu i ld ing . 9 .13
T he b arca s errana b u i ld ing s equence .
9 2
9 .14
T he w ide h u l l o f t he s ave iro .
9 3
9 .15
The p etrog l iph o f Berna .
9 4
9 .16
The p e trog liphs o f S tenkyrka , Go t land a nd o f H aggeby .
9 4
9 .17
An h ippos c o mpared w i th t he f ore ign s h ip c arved o n t he
9 6
Gebe l-e l-Araq k n i fe . 9 .18 9 .19
C aparica : mag ic e ye p a in ted o n t he b ow o f al oca l c ra f t .
9 7
B a lee ira ( Sagres/A lgarve ) : s tone a nchors u sed i n
9 7
c onven t iona l v esse ls. 9 .20
The r ound v esse ls a ppear ing o n Aegean a nd C re tan
9 8
s ea ls a round 2 200/2000 B . C. 9 .21
A c ra f t f ro m a S umer ian c y linder-sea l , mode ls o f p ro to-
9 9
d ynas t ic Egyp t ian c ra f t , a nd a s i lver mode l o f t he I I n ter med ia te Per iod . 9 .22 9 .23
De ta i ls f ro m d e Hag ia T r iada p a in t ing .
1 00
T he d ispersion o f S ou th P en insu lar p opu la t ions a f ter
1 01
t he f a l l o f Tar tessus c o mpared w i th t he migra t ion r ou tes o f t he s ave iro a nd s im i lar c ra f t .
F igure
P age
9 .24
The ma in l i nes o f westbound p rogression .
1 02
9 .25
V i la Franca d e X ira :b oa t-houses o f t he " sea g ipsies" .
1 04
T he b asic d a ta f or t he Poo le l ogboa t , c o mpi led f ro m
1 16
1 0.1
t he i n for ma tion a va i lab le b e fore t he l ogboa t was r ecorded . 1 0 .2
A r ecord o f t he P oo le l ogboa t , c o mp i led i n August
1 16
1 974. 1 0 .3
T he c a lcu la t ion o f t angen t ia l a nd r ad ia l s hr inkage
1 18
f actors. 1 0 .4
T he r e ma ins o f t he P oo le l ogboa t r ecorded i n
1 21
August 1 974. 1 0 .5
T he h ypothet ica l r econstruc t ion d rawing o f t he
1 21
P oo le l ogboa t , a f ter a n a l lowance h as b een made f or s hr inkage . 1 0 .6
The h ydrosta t ic c urves f or t he P oo le l ogboa t r econs truc t ion c o mpi led b y Burness ,
1 0 .7
1 23
C or le t t a nd P ar tners.
T he G igg leswick T arn l ogboa t t e mporar i ly r e-asse mb led ,
1 29
w i th o ne o f t he l ong i tudina l t imbers i n t he f oreground . 1 1.1
T ab le o f P lank B oa t f ea tures.
1 41
1 1.2
The S hor t F erry d ugout.
1 43
1 1.3
The d ugou t L ough L ynch 1 .
1 43
1 1.4
T he d ugou t f ro m L lyn L langorse .
1 46
1 1.5
L oad p lot ted a gainst f reeboard f or a C anad ian C anoe .
1 48
Behav iour o f t he b oundary l ayer a round a t yp ica l
1 50
1 1.6
y ach t h u ll . 1 1.7
The r esistance o f at yp ica l y ach t h u ll .
1 52
1 1.8
The r esistance c urve o f t he G okstad f aer ing r ep l ica .
1 53
1 2.1
Exa mp le o f a n e xcava t ion p lan .
1 67
The S even th-
C en tury Byzan t ine wreck f ound a t Yass i Ada . 1 2.2
Exa mp le o f ar econstruct ion p lan .
The B yzan tine
1 67
Yassi Ada wreck . 1 2.3
E xa mp le o f a1 :10 s ca le d rawing o f h u l l p lank f ro m
1 67
t he Graveney B oa t . 1 2.4
Trac ing i n f u l l s ca le o f aS ku lde lev V ik ing S h ip
1 68
f ra me o n to a c lear d ra f t ing f o lio . 1 2 .5 1 2.6
Pr inc ip les o f f u l l s ca le t racing o n t ransparen t f o l io .
1 69
Tracing o f ap lank f ro m S ku lde lev 1 c o mpared w i th
1 69
t he f rag men ts a f ter c onserva t ion .
v i
P age
F igure 1 2.7
Arrange men t f or r eproducing f u l l s ca le t rac ings
1 70
i n s ca le 1 :10 . 1 2.8
E xa mp le o f af u l l s ca le t racing o f h u l l p lank f ro m
1 70
t he S ku lde lev 1 S h ip . 1 2.9
E xa mp le o f s ca le d rawings o f a l l e le men ts o f a f rag men tary b oa t f ind .
1 75
The Egernsund b arge , f ro m
s ou thern D en mark . 1 2.10
P r im i tive " exp loded d raw ing" i l lustra t ing t he s truc-
1 75
t ura l l ay-ou t o f t he e nds o f t he Egernsund b arge . 1 2.11
The Egernsund b arge , r econstruct ion p lan .
1 75
1 3.1
T he S u t ton H oo s h ip l ook ing t owards t he b ow .
1 84
R econstruc ted c ross s ec tions o f t he k ee l , s te m , a nd
1 88
1 3.2
g unwa le s trake o f t he S u t ton H oo s h ip. 1 3.3 1 4 .1
The Graveney Boa t .
1 85
P ro jec tion p lan o f p ar t o f t he k ee l o f t he S kepparga tan
1 92
b oa t . 1 4.2
P ro jec t ion p lan o f as ec t ion o f p lank ing .
1 93
1 4.3
T he s urv iv ing p ar t o f t he k ee l w i th t he k ee l-ste m s car f .
1 94
1 4 .4
F u l l-sca le d ocu men ta tion o f b o th s ides o f al oose s ide p lank .
1 96
1 4 .5
S trake d iagra m o f o ne o f t he s urv iv ing s ec tions o f p lank ing .
1 97
1 4.6
R ecording t oo l marks o n t he S kepparga tan b oa t .
1 98
1 5 .1
S o me f or ms o f s tern c onsidered d ur ing t he h ypothe t ica l
2 08
r econstruc t ion o f t he Graveney B oa t . 1 5 .2
Hu l l f or ms f ro m d i f feren t s haped p lank e dges.
2 08
1 5 .3
En ig mas.
2 11
1 6.1
A mode l o f t he r e ma ins o f F err iby b oa t 1 .
2 17
Ah ypo thet ica l r econstruc tion o f aF err iby b oa t -
2 17
1 6 .2
min i mu m s olu tion w i th t wo s ide s trakes . 1 6.3
Ano ther p ossib le r econstruct ion - w i th t hree s trakes
2 20
a nd c losed e nds. 1 6 .4
At h ird r econs truction - t wo t imber s trakes w i th a h ide s heerstrake a nd a h ogg ing t russ. v i i
2 20
F igure
Page
1 6.5
T ransverse s tabi l i ty d iagra m .
2 24
1 6 .6
C on jectura l r owing a rrange men ts f or a t r ire me .
2 24
1 8 .1
A r ep lica o f t he Nyda m b oa t b u i l t i n 1 935 f or u se
2 46
i n aG er man f i lm . 1 8 .2
V ik ing , Magnus Andersen 's 1 893 r ep lica o f t he
2 47
Gokstad s h ip . 1 8 .3
V iking i n t he N or th S ea , w i th a f oresai l i n a ddi t ion
2 47
t o h er s quare ma insa i l . 1 8 .4
Hug in . The 1 949 Dan ish r ep lica o f t he G okstad s h ip .
2 48
1 8 .5
T he Dan ish Na t iona l Museu m 's N or land O t tr ing .
2 48
1 8 .6
The G okstad f aering c onstruc t ion p lan b y Arne Em i l
2 50
C hr istensen . 1 8 .7
The f ore s te m a nd t he f orward i nc l ined f ra me o f t he
2 52
G reenwich f aer ing r ep lica . 1 8 .8
A s im i lar v iew o f t he f aer ing r ep lica b u i l t b y
2 52
Egon H ansen a t Moes e Ard . 1 8 .9
T he r udder b oss o n t he G reenw ich f aer ing r ep l ica .
2 52
1 8 .10
The Greenwich f aer ing r ep lica u nder o ars.
2 53
1 8 .11
The Greenwich f aer ing r ep l ica u nder s a i l .
2 53
1 9 .1
S che ma tic d rawing o f t he o r ig ina l p lanned l ayou t
2 61
o f Brendan . 1 9 .2
T he s ke le ton o f a1 :12 s ca le mode l o f Brendan .
2 61
1 9 .3
S ea t r ia ls o f Brendan o f f C oun ty C ork , S pr ing 1 976.
2 63
1 9 .4
Brendan 's s teer ing g ear .
2 63
2 0 .1
The Gokstad f aer ing , a nd t he Ose lver b oa t .
2 72
2 0 .2
S hel l b u i ld ing t echn iques i n d if feren t r eg ions.
2 78
2 2 .1
F or mer c hanne ls o f t he R iver Tha mes a t Ox ford .
2 90
2 2.2
Two p ossib ly impor tan t a reas f or b oa t f inds o n t he
2 91
R iver T ha mes a bove Ox ford . 2 2. 3
B oa ts a t t he mou th o f t he F lee t R iver , L ondon i n 1 676.
v i i i
2 93
ED ITOR 'S I NTRODUCT ION
T he s uggest ion t ha t aS y mpos iu m o n Boa t Archaeo logy s hou ld b e h e ld c a me f ro m E . V . Wr igh t , e xcava tor o f t he Bronze Age F err iby b oats , a nd a Trustee o f t he Na t iona l Mar it i me Museu m.
The i dea was warm ly we lco med b y Bas il
Greenh il l , D irec tor o f t he Museu m , who n om inated a sma l l c o mm it tee t o d et erm ine t he t he mes t o b e d iscussed a nd t o i nv ite t he p r inc ip le s peakers. T h is o rgan is ing c o mm ittee a i med t o b r ing t ogether a l l t hose i nvo lved i n t he s tudy o f t he f orm , s tructure , f unct ion , a nd o pera t iona l p er formance o f a nc ien t b oats.
I n t h is c on tex t t he word b oa t was u sed a s ac onven ien t s hor thand f or
a l l f or ms o f w a ter t ranspor tb u il t b y h and.
I t was h oped t ha t t h is g a ther ing
w ou ld t ake s tock o f t he " sta te o f t he a r t" , a nd c r it ica l ly e va lua te t he methods a nd t echn iques c urren t ly i nu se. T he S ympos iu m was h e ld f ro m 2 0th t o 2 4th S ep te mber 1 976 , a t t he Nat iona l Mar it i me Museu m Greenw ich , a nd was a t tended b y 8 5 p eop le f ro m 1 0 d if feren t c oun tr ies , a s f ar a par t a s N orway a nd Austra l ia , Sw itzer land a nd Nor th Amer ica.
Che m ists , B otan ists , Nava l Arch itec ts , Eng ineers , Co mpu ter a nd
I n forma t ion S c ien t ists , H istor ians , D ivers , T e lev is ion Producers , Ed itors , Boa tbu i lders , a nd E thnographers a s w el l a s Archaeo log is ts , w ere t here , r ef l ect ing n o t o n ly t he w ide r ang ing a ppea l o f t h is s ub ject , b u t a lso t he mu l t id isc ip l inary a pproach n ow r equ ired i n Boa t Archaeo logy . T he o rgan is ing c o mm it tee d id n o t a t te mp t t o i nc lude i n t he p rogra mme a l l f orms o f e v idence o r a l l t echn iques u sed b yb oa t a rchaeo log ists , b ut c oncent ra ted o n t hose t op ics i tb e l ieved t o b e e spec ia l ly i mpor tan t .
Our n on-nau t ica l
c o l leagues s hou ld n ote t ha t t hese a re n o t e xc lus ive ly n aut ica l t op ics b eyond t he k en o f t he l and a rchaeo log ist , f or o f t he 8 t he mes c ons idered a t t he S ympos iu m , c onserva t ion , e thnography , q uan t ita t ive methods , r ecord ing , h ypothet ica l r ec ons truc t ions , a nd e xper i men ta l w ork , a re a l l o f d irect c oncern t o o ther b ranches b ranches o f a rchaeo logy ; wh i lst t he r e ma in ing t he mes - a g lossary o f t er ms , a nd a nc ien t b oatbu i ld ing - must b e o f w ide i n teres t , f or t he p rob le ms o f t he o ne a nd t he methodo logy o f t he o ther a re c om mon t o t he who le a rchaeo log ica l d isc ip l ine. Authors p resen ted t he ma in p o in ts o f t he ir p apers t o t he S ympos ium i n t a lks o f 2 0 minu tes d urat ion .
Each ma in t he me, c ons ist ing o f t wo p apers ,
w as t hen d iscussed i n h our l ong s ess ions wh ich w ere r ecorded .
Ed ited
v ers ions o f t hese d iscuss ions a re p ub l ished h ere , i m med ia te ly a f ter t he ir a ssoc ia ted p apers. T he p apers b y C . W. Gregson a nd J . Roe lfze ma w ere n o t p resen ted a t t he S ympos iu m , b u t t hey a re p ub l ished n ow b ecause t hey a dd t o t he t he me o n t he c onserva t ion o f wa ter logged wood , wh ich i s , a f ter a l l , t he p r inc ip le r aw mater ia l o fb oa t a rchaeo logy a nd t hus o f g reat impor tance. T he p apers b y Car l O lof C eder lund , T i mothy S ever in , a nd Dav id S turdy were p resen ted i n a
i x
s ess ion f or s e lec ted s hor t p apers , c ha ired b y E . V . Wr igh t ;
t hey a re h ere
p ub l ished u nder t he ir r e levan t t he me h ead ings . I tw as p lanned t hat , a f ter t he f orma l c onc lus ion o f t he S ympos iu m , Hag Ah med Youssef Musta fa t he a rchaeo log ist i n c harge o f t he Cheops S h ip , s hou ld g ive a n i l lustrated l ecture o n t h is mos t i mpor tan t f ind .
I n t he e ven t , t he Hag
was u nab le t o a t tend t he S ympos iu m , a nd a t t he l ast m inu te , h is Br it ish c o ll aborator , R ichard Wa l ter , d epu t ised f or h im . Regretab ly , i th as n o t p roved p oss ib le t o o b ta in p er m iss ion f ro m t he Egyp t ian a u thor it ies f or Wa l ter 's p resen ta t ion t o b e p ub l ished. Ih ave n ot s tandard ised t he s yste ms o f r eferences u sed b y t h is i n terna t iona l b and o f a uthors , n or h ave Ia t te mp ted t o e nsure u n iform u sage o f t echn ica l t er ms. A t t he p resen t s tage o f d eve lopmen t o f b oa t a rchaeo logy , t h is l a t ter w ou ld b e a n i mposs ib le t ask , a s t he G lossary p aper b y J . E . G . McKee , a nd t he s ubsequen t d iscuss ion s how . T erms s uch a s r ib , l u t ing , c arve l , c an mean d i f feren t t h ings t o d i f feren t a u thors. N ever the less , t o h e lp t he n onn aut ica l r eader , e x trac t f ro m t wo o f t he most r ecen t g lossar ies - b y Bas i l Greenh i l l , a nd b y E . V . Wr igh t -a re a ppended . T hese s hou ld r eso lve t he mean ing o f most t erms , e xcep t p oss ib ly t he word c arve l , wh ich , i fw e f o l low Bas i l Greenh il l 's a dv ice , may i n f uture f a l l i n to d isuse , o r b e r estr icted t o v esse ls b u i lt o f p lanks n ot j o ined t oge ther a t t he ir e dges , b u t f astened t o p ree rec ted f ra mes wh ich d eterm ine t he s hape o f t he f i n ished v esse l. One o f t he most p leas ing a spec ts o f t he S ympos iu m was t he p roposa l b y Professor S verre Marstrander , v o ic ing t he s pon taneous s ugges t ion o f many d e legates , t ha t ap ermanen t o rgan isa t ion o f b oa t a rchaeo log ists s hou ld b e f ormed. A p rov is iona l c omm it tee was e lec ted b y t he S ympos iu m t o u ndert ake t h is t ask , a nd i ti s e nv isaged t ha t t h is o rgan isa t ion w i l l n ot o n ly a rrange f u ture S ympos ia , b u t a lso t ack le s uch i n terna t iona l p rob le ms a s t he s tandardi sat ion o f t echn ica l t erms a nd t he h armon isa t ion o f r ecord ing methods , a nd i nvest iga te t he p oss ib i l it ies o f a n i n ternat iona l d a ta b ank . Iw ish t o t hank Mrs. Tr ic ia H itchcock who t ranscr ibed t he t apes o f t he d iscuss ion p er iods a nd c oped mos t e f fec t ive ly w ith t h is o f ten d i f f icu l t t ask , a nd Mrs. G ianne l la N ico l who t yped t he e d ited d iscuss ions a nd o ther s uppor ti ng s ect ions o f t h is p ub l ica t ion i n d ef iance o f my h andwr it ing .
S ean McGra i l Ed itor
L IST OF CONTR IBUTORS
Car l O lof Ceder lund f i l.l ic. Cura tor , S ta tens S j0h istor iska Museu m , S tockho lm Arne Em il Chr is tensen M.A. Cura tor , Un ivers ity Co l lec t ion o f Na t iona l An t iqu it ies , V ik ing S h ip Museu m , Os lo J . F . Coates M.A., F .R .I. N .A., R .C. N .C. Depu ty D irector o f Nava l Cons truc t ion , M in istry o f D efence , Ba th J . M. Coles M.A., P h .D., F .S .A. Reader i n European Preh istory , Un ivers ity o f Ca mbr idge O le Cru m l in-Pedersen D irector , V ik ing S h ip Museu m , Rosk i lde , Den mark J . d e J ong I Jsse l meerpo lders D eve lop men t Au thor i ty , Le lys tad , N ether lands Ange la Care Evans
B .A., F .S.A.
S en ior Research Ass is tan t , Dep t . o f Med iaeva l &L a ter An t iqu it ies , Br it ish Museu m , L ondon Octav io L ixa F ilgue iras Pro fessor o f Arch itecture , Esco la S uper ior d e Be las A r tes , Opor to , a nd D irector , Depar tmen t o f N ava l E thno logy , Cen tre f or H istor ica l S tud ies , Un ivers ity o f Opor to
J . M. Graha m , B .A., M.Sc. L ecturer , Depar t men t o f Co mpu ter S c ience , Un ivers ity o f Read ing Bas i l Greenh i l l C .M .G ., B .A., F .S .A., F .R. H ist.S. -D irector , Na t iona l Mar it i me Museu m , Greenw ich C . W. Gregson N .D .D ., A .T .0 ,D ip . Cons. Conserva t ion Of f icer , Archaeo log ica l Research Cen tre , Na t iona l Mar it i me Museu m , Greenw ich O lof Hass löf Ph .D. F or mer ly Curator a t t he S j0h istor iska Museu m , S tockho lm , a nd Professor a t t he Un ivers ity o f Copenhagen J . F . L evy D .Sc., A .R .C.S ., F .I.B io l., F .I. W.Sc., F .I.A. W .S ., F . L.S. Reader i n Wood S c ience , Dep t . o f Bo tany , Imper ia l Co l lege , L ondon
x i
S ean McGra i l B .A. ,Mas ter Mar iner Ch ief Archaeo log ist , Archaeo log ica l Research C en tre , N a t iona l Mar it i me Museu m , Greenw ich. J . E . G . McKee 0 .B . E. Ca ird Research F el low , Na t iona l Mar it i me Museu m , Greenw ich P eter Marsden F . S .A . F ie ld O f f icer , Depar t men t o f Urban Archaeo logy , Museu m o f L ondon J . Roelfze ma Nay. Arch . L ecturer , Eng ineer ing Co l lege o f S c ience a nd T echno logy ( H .T .S . Ams terda m T i mothy S ever in , M. A., B .L it t . 1 6 Thanet S treet , L ondon WC1 Dav id S turdy M.A., B .L it t . 2 5 , Rona Road , L ondon NW3 Dav id M. Wilson L it t.D., F .S .A. D irector , The Br it ish Museu m , L ondon E . V . Wr igh t M.B.E., M.A., F .S .A. Trus tee , Na t iona l Mar it i me Museu m , G reenw ich
1 .
I NTRODUCTORY ADDRESS D av id Wi lson
On t he f irs t e ven ing o f t h is S y mposium we were p r iv i leged t o b e p resen t a t t he o pen ing o f a n e xh ibi t ion o f a rchaeo log ica l r esearch i n t he Z u ider Z ee ; t h is was a s p lend id o ccasion , s t i mu la t ing t o a l l a nd a f i t t ing p re lude t o o ur p roceed ings . On ly a f ter t he war was s er ious a rchaeo log ica l work o n n au t ica l a rchaeo logy i n i t ia ted i n t he N e ther lands - s ince t hen more t han 3 00 wrecks h ave b een r epor ted - most ly v esse ls u sed i n t he f i sh ing i ndus try , b u t s o me f ew b e ing med ieva l a nd l a ter merchan t s h ips , wh ich ( w i th t he f a mous Bre men C og ) e nab le u s t o u nders tand i n s o me measure t he me thods a nd c onstruc t ion a nd a ppearance o f v esse ls o therw ise o n ly k nown f ro m p a in t ings a nd l i terary t ex ts.
T he e xh ib i t ion s hows t h is , b u t a lso i l lu m ina tes many a reas o f e cono m-
i c s pecu la t ion - t rade , f i sh ing a nd s o o n - wh ich a re n o t p erhaps t he i m med ia te c oncern o f t h is S ymposiu m . N o t e very c oun try h as b een e i ther a s f or tuna te o r a s f ar-see ing a s Ho l land. Bu t g radua l ly we a re b eg inn ing t o a pprec ia te much more o f t he mar i t i me h ist ory o f E urope t hrough a rchaeo log ica l i nves t iga t ions .
T he work o f t he mar i-
t ime museu m i n G dansk a nd o f t he n ew ly-bu i l t Museu m a t R osk i lde , f or e xa mp le , h ave a dded e nor mously t o o ur k now ledge .
Bu t a l l o f u s c ou ld men-
t ion many f inds o f n ew b oa ts a nd n ew e v idence , f ro m Miku lcice i n C zechoslova k ia t o B ergen i n N orway , wh ich a re n ow b e ing s tud ied b y s cho lars. I n t h is c oun try we h ave n o t p erhaps b een s o f or tuna te n or s o e nerge t ic u n t i l c o mpara t ive ly r ecen t ly .
Mr . G reenh i l l 's r ecen t b ook a nd t he f ounda t ion
o f t he n ew Archaeo log ica l R esearch C en tre a t G reenwich , u nder Mr . McGra i l 's l eadersh ip , a ugur we l l f or t he f u ture .
We h ope t hese a re h arbingers o f b e t ter
t imes a head , a s Iam s ure a re t he h igh ly p ro fessiona l a pproaches o f u nderwa ter a rchaeo log ists l ike C o m mander B ax a nd h is t ea m who work o u t o f F or t B ov isand , t he n ew lyfounded u n i t a t S t . Andrew 's Un iversi ty u nder C o l in Mar t in , a nd t he Mary R ose t ea m . T o p eop le l ike myse l f who work i n t he f ie ld o f e ar ly med ieva l a rchaeo logy i n n or th-western E urope , t he p rob le ms o f s ea a nd r iver t ranspor t a re e verp resen t .
We a re f or tunate i n h av ing a f a ir ly b road-based k now ledge o f s h ips
a nd s h ip-bu i lding f ro m s urv iv ing r e ma ins a nd f ro m l i tera ture .
T he Osberg
s h ip , t he S ku lde ley f inds , t he An twerp v esse ls a nd t he G raveney b oa t h ave g iven u s af a ir i dea o f e ar ly med ieva l s h ipp ing i n n or thern wa ters .
When we
l ook a t o ur k now ledge o f sma l ler b oa ts we a re , h owever , i n av ery d i f feren t s i tua t ion .
Sma l l b oa ts a re l i t t le n o t iced ,
t he ir p er for mance i s t he s ub jec t o f
g uess-work a nd t he ir r e ma ins a re r are ly c her ished .
T h is s ure ly i s s o me-
t h ing we must l ook a t . I ti s It h ink i n terest ing a nd h ope fu l t ha t s o many s essions o f t h is c on fere nce s hou ld b e d evo ted t o d iscussions o f d e f in i t ion a nd r ecord ing .
H ere
s ure ly a re s o me o f t he ma jor p rob le ms.
S o me a nswers a re p rov ided h ere .
H ow d oes o ne d e f ine a l angsk ip f or e xa mp le?
A r ecen t ly p ub l ished b ook b y
ad ist ingu ished I ce land ic s pec ia l is t s ays t ha t t he G oks tad b oa t i s al angsk ip - whereas many p eop le wou ld s ay t ha t i s was a k ar f i . I n many ways Iam s orry we h ave n o H ja l mer F a lk - a p h i lo log is t -t o h e lp u s i n o ur s tudy . B asic measure men t i s a lso a p rob le m .
Wood s hr inks , b u t t he r econ-
s truc t ions p roduced b y p rac t ica l ly a l l s cho lars r are ly t ake a ccoun t o f t he way i n wh ich i td oes s hr ink .
Ad ug-ou t b oa t , f or e xa mp le , wh ich h as l a in f or y ears
i n t he b ase men t o f ac en tra l ly-hea ted museu m w i l l n owadays b ear l i t t le r e la t ion t o t he b oa t wh ich o nce f err ied p eop le a cross a l ake o r r iver . Iam p leased t oo , t o s ee t ha t e xper i men ta l a rchaeo logy i s s o much t o t he f ore i n t he d iscussions o f t he c on ference .
Iam d eep ly s orry t ha t P au l
J ohns ton 's u n t i me ly d ea th h as r obbed u s o f o ne o f t he most e n thusiast ic r epl i ca b u i lders .
Many w i l l h ave s een , o r w i l l h ave t he o ppor tun i ty t o s ee , t he
f i l ms h e made o f I r ish c urraghs a nd ( more p ar t icu lar ly ) o f t he B ronze Age s k in b oa ts p ostu la ted b y P ro fessor Mars trander o n t he b asis o f t he N orweg ian r ock e ngrav ings .
B u t t he work wh ich h e was s o g ood a t g oes o n , a nd S ean
McGra i l w i l l b e t a lk ing a bou t t he p rac tica l a spec ts o f t h is v ery i mpor tan t s ub jec t a nd J ohn C o les w i l l t a lk a bou t t he p r incip les i nvo lved i n mak ing r epl i cas . A s a n Eng l ish man Ip art icu lar ly c o m mend t he p apers p resen ted b y Pro fessors F i lgue iras a nd H ass l e i f ; f or i n t h is c oun try o ne o f t he t h ings most n eg lec ted i n a rchaeo logy i s t he s tudy o f e thnograph ica l p ara l le ls .
Our me thods
h ere a re s o me t i mes mudd led , a s we h ave v ery l i t t le c on te mporary e thnograph ic ma ter ia ls i n many o f t he f i e lds f ound o n t he c on t inen t , b u t Iam s ure we c an l earn much h ere f ro m o ur c on t inen ta l c o l leagues. I n we lco m ing y ou t o wha t i s a mos t u se fu l a nd l i ve ly S y mposiu m , Iwou ld l ike t o e x -press o ur t hanks t o Mr . G reenh i l l a nd t he me mbers o f h is s ta f f f or whe t t ing o ur a ppe t i tes i n t he p roduc t ion o f t h is p rogra m me . P ar t icu lar ly , h owever , It h ink we mus t b e mos t g ra te fu l t o b e mee t ing i n t h is Museu m , s ure ly o ne o f t he most s p lend id s i tes o f a ny n au t ica l museu m i n t he wor ld .
2
2 .
S ETT ING THE S CENE E .V . Wr igh t S u m mary
T h is p aper o f fers a n o u t l ine o f t he ma ter ia l a va i lab le f or t he s tudy o f B oat A rchaeo logy i n B r i ta in i n c hrono log ica l o rder f ro m t he Meso l i th ic t o t he b eg inn ing o f p rec ise h is tor ica l r ecords. A l though s parse e xcep t f or d ugou ts a nd u n t i l r ecen t ly p a in fu l ly i l l r ecorded , t he r ange o f t ypes i s w ide . o f ten i nadequa te .
D a t ing e v idence i s a lso
C ond i tions i n t he B r i t ish I s les f or s urv iva l o f
a c tua l b oa t-re ma ins a re g ood a nd t h is i s a t tested b y t he g rowing l i s t o f f inds i n t he l ast q uar ter c en tury . T he s econd p ar t o f t he p aper s uggests i n b r ie f as yste ma t ic a pproach t o c on tro l , i nvest iga t ion , r ecovery a nd r esearch f o l lowing ad iscovery .
Iam p r iv i leged a s a n " invo lved t rus tee" o f t he N a t iona l Mar i t i me Museum t o o f fer a n i n troductory p aper f or t h is o ur f our th s y mpos iu m o n t op ics r e la ted t o a rchaeo logy .
T he f irst o n " Aspec ts o f t he H is tory o f Wooden S h ipbu i ld ing"
t ook p lace i n March 1 969 ; t he s econd o n " Three Ma jor Anc ien t B oa t F inds i n B r i ta in" i n 1 971 ; a nd t he t h ird o n t he o f ten c r i t ica l t echn iques o f "Wa ter logged Wood Conserva t ion" i n 1 973. The t he me f or t h is more amb it ious g ather ing i s " Archaeo logy o f t he B oa t" i t se l f a nd i tp rov ides u s w i th a n o ppor tun i ty t o e sta b l ish o r i n f luence i n t h is c oun try a n umber o f b asic d iscip l ines r e levan t t o o ur s pec ia l ised b ranch o f t he a rchaeo log ica l s c ience o r a r t . S ince t he 1 971 S y mposium a n u mber o f i mpor tan t e ven ts h ave o ccurred i n t h is c oun try . P ub l ica t ions i nc lude t he d e f in i t ive r epor t o n t he S u t ton H oo S h ip i n Vo lu me 1 o f " The S u t ton H oo S h ip-Bur ia l" a nd we s ha l l s oon h ave t ha t o n " The G raveney B oa t" .
Af u l ler b u t b y n o means f ina l a ccoun t o f t he N or th
F err iby B oa ts i s made a va i lab le i n t he g u ide-book i ssued t h is mon th b y t he N a t iona l Mar i t i me Museu m .
B as i l G reenh i l l 's n ew b ook " Archaeo logy o f t he
B oa t" f i l ls t he g ap i n Eng l ish l e f t b y t he o bso lescence o f s uch a n i nd ispensab le c lass ic a s J a mes Horne l l 's "Water T ranspor t".
Unques t ionab ly a n impor t-
a n t e xcava t ion h as b een S ean McGra i l 's o f t he Br igg " Ra f t" wh ich h as a lready b een t he s ub jec t o f ap re l im inary p ub l ished n o te.
No tab le a c t iv ity i n t he
a rea o f c onstruc t ion a nd t r ia ls o f ar ep l ica h as b een t he work o f Er ic McKee a nd S ean McGra il w ith t he G okstad f aer ing .
F ina l ly a nd b y n o means l eas t ,
w e h ave h ere a t Greenw ich a n e s tab l ished Archaeo log ica l Research C en tre w ith f ac il it ies t o c onduc t r esearch a nd c onserva t ion a nd a lso t o g u ide o thers who may n eed h e lp b oth i n Br ita in a nd e lsewhere.
3
I ti s t ime ly , t here fore , t ha t we s hou ld t o s o me e x ten t t ake s tock o f t he s ta te o f an u mber o f a spec ts o f b oa t a rchaeo logy , e spec ia l ly a s i tc oncerns N or th West E urope ; e xpose i deas , s o me o f wh ich may h e n ove l , t o c r i t ica l i n terna t iona l r ev iew ; d raw o n t he e xper ience o f o ur i n terna t iona l f e l lowworkers ; a nd , we h ope , emerge w i th i mproved e qu ip men t -i n me thods , t er m ino logy a nd s k i l ls -t o mee t t he c ha l lenges o f t he f u ture .
C onfession t hey
s ay i s g ood f or t he s ou l a nd Ih ave n o h es ita t ion t herefore i n a cknow ledg ing t ha t t he p as t r ecord i n t h is c oun try h as b een l a men tab le . It rus t t ha t o ur c o l leagues f ro m a broad w i l l r ecogn ise t ha t o ur h ouse i s n ow i n b e t ter o rder a nd j o in w i th u s h ere i n a dvanc ing o ur s c ience i n terna t iona l ly . I n s e t t ing t he s cene f or o ur p roceed ings t h is week Ii n tend t o d eve lop t wo c o mp le men tary l i nes , t he o ne ma ter ia l a nd t he o ther a bstrac t .
Is hou ld ,
h owever , emphas ise t ha t my a pproach i n e ach c ase w i l l l ean t owards t he p rac t ica l a nd t ang ib le r a ther t han t he t heore t ica l .
Ih ave h ad p ersona l e x-
p er ience o f t he t e mp ta t ion t o t heor ise o n t he b asis o f l im i ted e v idence , a t e mp ta t ion wh ich i s a s d i f f icu l t t o r esist i n B oa t Archaeo logy a s i n a ny b ranch , n o t l east b ecause f i nds a re r are a nd b y t he ir n a ture o f ten d ra ma t ic .
N ever-
t he less , a measure o f c on tro l led e xc i te men t i s n o t e n t ire ly o u t o f p lace s ince b oa ts a nd s h ips a re t he l arges t a nd among t he mos t c o mp lex movab le s truc tu res a t te mp ted b y man t hroughou t h is h is tory a nd a s s uch o f fer much i nsigh t i n to t echn ica l c apab i l i ty a nd o rgan isa t ion t hrough t he a ges.
T h is a nd t he
c ircu mstances o f d iscovery a nd e xcava t ion , wh ich a re s e ldo m w i thou t d ra ma a nd emergency , c o mb ine t o make t he s tudy a nd r epor t ing o f e p isodes i n mar it i me a rchaeo logy o f u nusua l i n terest n o t o n ly t o t he e xper t b u t t o t he g enera l p ub l ic a lso . T he f irst p ar t o f t h is p aper i s a n a t te mp t t o o rder t he r egre t tab ly s parse ma ter ia l a va i lab le i n B r i ta in s o a s t o p resen t t he o ppor tun i ty o pen t o u s a nd t he j ust i f ica t ion f or a pp ly ing r esources t o t he s tudy .
T he s econd c on ta ins s o me
r e f lec t ions o n t he me thod o f a pproach wh ich l i es b eh ind o ur p o l icy f or t he d eve lop men t o f as pec ia l ised f ac i l i ty i n t he N a t iona l Mar i t i me Museu m a nd i t s work .
T h is i n t urn h as g u ided t he c omm i t tee i n f ra m ing t he p rogra m me f or
t h is s y mposiu m . T he b as ic n eeds wh ich h ave i nduced man t o b u i ld b oa ts c an b e r educed t o r e la t ive ly f ew a nd i n t he ma in t hey h ave n ot v ar ied much o ver t he a ges.
I
s uggest t hese a s t he mos t i mpor tan t :F ood-ga ther ing : f i sh ing ,
f ow l ing ,
e tc .
T rave l a nd t ranspor t o f g oods b y wa terway a s a n a l terna t ive t o l and . C rossing o f wa ter o bs tac les o f wha tever w id th : f or p urposes o f t rave l , t ranspor t , e xp lora t ion , e tc . War C ere mon ia l a nd R e l ig ious o bservance P leasure A l l b ut t he l ast t wo f igure i n t he ma ter ia l r ecord o f f i nds f ro m Br ita in w h ich f a l l i n to my own s ugges ted c a tegory a s p roper ly o f a rchaeo log ica l r a ther t han h istor ica l c oncern .
Ip ersona l ly d e f ine t he l a t ter a s c o mprehend ing t hose
4
c overed b y t he s or t o f wr i t ten r ecords s uch a s s urv ive i n t h is c oun try f ro m t he l a t ter y ears o f t he s ix teen th c en tury o nwards. C hrono log ica l ly t he e ar l ies t d a ted t race o f b oa t ing a c t iv i ty i n t he B r i t ish I s les i s t he e ar ly Meso l i th ic p add le f ro m S tar C arr u nca l ibra ted r ad iocarbon y ears) .
7 ,5 00 b .c . ,i .e . i n
N o b oa t was f ound n ear t he s e t t le men t
s i te d esp i te d e l ibera te e x tension o f t he e xcava t ion i n t he most l i ke ly d irec t ion , n or was t he a va i lable t imber i n t he a rea ( B irch ) t hough t t o b e s u i tab le f or c ons truc t ion o f d ugou t b oa ts.
T he i n ference was , t here fore , t ha t s o me f or m
o f s k in-boa t m igh t h ave b een u sed ( C lark : E xcava t ions a t S tar C arr C a mbr idge 1 954 ) .
There i s ad ugou t " da ted s tra t igraph ica l ly" t o t he Meso l i th ic a s we l l
a s p add les f ro m S co t land , b u t t he b oa t h as n o t y e t b een s ecure ly d a ted . d eed t he o n ly a c tua l b oa t s o f ar s a fe ly a t tr ibu tab le
I n-
t o t he Meso l i th ic a ppears
t o b e t he Dren the d ugou t ( van d er H e ide i n h is p aper t o t he f i rst o f t hese Greenwich a rchaeo log ica l s y mposia , s ta tes t ha t i t" cou ld b e d a ted b y r ad ioc arbon a t 8 ,0 00 y ears o ld ) .
A t t h is p er iod B r i tain 's l andl inks w i th t he
ma in land h ad n o t b een s evered b y r is ing p ost-g lac ia l s ealeve ls.
T h is i s
b e l ieved t o h ave o ccurred a t t he e nd o f t he B orea l c l i ma t ic p hase p erhaps a bou t 5 ,5 00-5 , 0 00 b .c .
A t t h is p o in t Is hou ld men t ion t ha t If o l low t he c on-
v en t ion o f e xpressing c a lendar o r t rue y ears a s B . C.,
A .D . o r B .P. ( Be fore
P resen t t aken a s 1 950 A .D .) a nd r ad iocarbon y ears , wh ich b e fore t he C hr is t ian e ra a t l east s ign i f ican t ly u ndersta te t he t rue a ge , a s b .c ., a .d . o r b .p .
T here i s n o t y e t a n u n iversa l ly a ccep ted me thod o f c a l ibra t ing r ad io-
c arbon y ears w i th c a lendar y ears b u t t he most r ecen t B r i t ish work o n t he s ub jec t i s R . M. C lark 's i n An t iqu i ty Vo l . 4 9 , 1 975 . A f ter t he e nd o f t he B orea l p hase we a re f aced w i th t he u nden iab le f ac t t ha t wha t was b y t hen a n a rch ipe lago was v isi ted a nd s e t t led b y N eo l i th ic f ar m ing p eop le f ro m t he ma in land we l l b e fore 4 ,000 B .C . a nd t ha t t hey c ou ld o n ly h ave a ch ieved t h is p assage o f t he n arrow s eas w i th t he ir d o mes t ic a n i ma ls , c a t t le i n p ar t icu lar , i n b oa ts o f s ubstan t ia l c arry ing c apac i ty a nd s eawor th iness. We d o n o t k now f or c er ta in wha t t hese b oa ts were , t he e ar l ies t b oa ts s o f ar d a ted b e ing t he B ran thwa i te a nd C hape l F la t Dyke d ugou ts o f c . 2 ,000 B .C ., a l though t here a re s evera l d ugou ts wh ich h ave b een a scr ibed t o t he N eo l i th ic b y a ssoc ia t ion , e .g ., t ha t f ro m t he E r i th marshes wh ich c on ta ined a p o l ished f l in t a xe a nd a s craper . F or t he e ar l ier B ronze Age t oo we h ave c lear i nd ica t ion o f o versea c ont ac ts f ro m t he p resence o f " Beaker" e le men ts f ro m a bou t t he mid 3 rd mi l lenn iu m ,
n o tab ly t he c onnec t ions b e tween t he s ou th-west a nd B r i t tany wh ich a re
g enera l ly a ccep ted .
More p os i t ive e v idence f or s ea-tra f f ic c o mes f ro m t he
r ecen t d iscovery b y s k in-d ivers o f ah oard o f e ar ly b ronze a xes o f f t he Ken t ish c oast .
I ti s b eyond a rgu men t t ha t t here was s uch t ra f f ic a cross t he
C hanne l a nd t he I r ish S ea a t i n terva ls t hroughou t t he B ronze Age a nd t herea f ter t he E ar ly I ron Age u n t i l t he h is tor ica l r ecord b eg ins.
And y e t , f or a l l
t ha t we a re c on f iden t t ha t v oyages were made , we k now v ery l i t t le i ndeed f or c er ta in a bou t t he b oa ts u sed i n p reh istor ic t imes . We c an b e s ure o f d ugou ts f or many c en tur ies a nd McGra i l a nd S wi tsur 's work emphasises t ha t t he r ad iocarbon-da ted s pan s hows t he m i n u se a t l east f ro m 2 , 0 00 B .C . d own t o 1 ,0 00 A .D . ,l ong a f ter more s oph ist ica ted me thods o f b oa t-bu i ld ing h ad b eco me a va i lab le .
5
We a re f or tuna te t o h ave t he o n ly
e xamp les o f Bronze Age p lanked b oa ts k nown s o f ar f ro m Wes tern Europe , t he t hree N or th F err iby f ragmen ts a nd t he l a ter Br igg " Raf t".
F or o ther
f orms o f p reh istor ic b oa t t he s o le e v idence i sd ocu mentary , Caesar 's r eference t o s k in-boa ts i n Br ita in , a n i dea w h ich h is a rmy c op ied i n S pa in . Wha tever t ime-span may b e a ssu med f or t he mak ing o f s k in-boats i n t hese i s lands , o r e lsewhere , i n a n t iqu ity t he o ldes t d atab le r eference t o t he ir u se i n Br ita in i s o f t he i s t c en tury B .C. I ti s , o f c ourse , v ery l ike ly t ha t t hey w ere made i n p re- meta l a ges ; b u t n o a nc ien t e xamp les h ave b een f ound f or c er ta in , a lthough t here i s ad oub t fu l ly a u then t ic r epor t o f a" corac le" f ro m a b r ickyard a t S ou th F err iby . F or s h ips o f t he Ro man p er iod L ondon R iver h as b een c o mpara t ive ly r ich i n i t s y ie ld w ith t he t wo f i nds f ro m B lack fr iars a nd New G uy 's House , d a ted t o t he 2 nd c entury A .D . ,a nd t he r a ther l a ter C oun ty Ha l l v esse l l i f ted i n 1 910. Fro m S axon t imes S ut ton Hoo h as g iven u p a l l i t s g host ly e v idence a nd t he t imely d iscovery o f t he w el l-preserved r e ma ins o f t he G raveney b oat p rov ides ma ter ia l o f t he q ua l ity s o b ad ly n eeded f or d e ta iled a nd t horough t echn ic a l s tudy u s ing modern methods. I t w il l b e s urpr is ing i fw e a re n ot c on fron ted b efore many y ears w ith med ieva l f i nds c a l l ing f or " rescue" e xcava t ion a nd l e t i tn o t b e f orgot ten t hat t he b o t to m o f t he h u l l o f t he G race D ieu o f 1 418 l i es i n t he Ha mb le R iver awa it ing a tten t ion , i fi te ver b e t hough t j us t if iab le t o a pp ly ma jor r esources t o t he t ask . I n v ar iety a nd t ime-range w e a re most f or tuna te ly p laced i n wha t h as b een d iscovered , t hough p erhaps l ess s o i n t he p ast s tandards o f r ecord ing a nd r epor t ing .
T h is w e t rust h as n ow b een p u t r igh t , a s a lso h as f ac il ity f or c on-
s erva t ion i n t hose c ases where i ti s p ract ica l ly a nd e cono m ica l ly f eas ib le. Wha t , Is ugges t , s hou ld f o l low i s t he d e l ibera te p ursu it o f ap o l icy t o s eek o ut a nswers t o q ues t ions p osed s o a s t o f i l l t he g aps i n o ur k now ledge. S ome o f t h is c an b e t ack led u s ing f i nds a nd t he e v idence t o b e g a ined f ro m t hem i n a c on tro l led f ash ion a nd t o ap lanned p rogra mme. T h is i s p ar t icu lar ly t rue o f e xper i men ts i n u se o f mater ia ls , e ssays i n r econs truc t ion a nd t he mak ing a nd t r ia ltes t ing o f r ep l icas.
Wha t c annot u n for tuna te ly b e c on tro l led i s t he d is-
c overy o f a dd it iona l ma ter ia l , e spec ia l ly e xamp les o f t ypes f ro m p er iods a t p resen t l i t t le k nown . Id o , h owever , s tress t he f ac t t ha t i n t he e stuar ies a nd waterways o f t he e astern h a l f o f Eng land c ond it ionslead ing t o p reserva t ion a nd p oss ib le d iscovery o f a nc ien t b oa ts a re u nusua l ly f avourab le. Happ i ly , more p eop le w ith s o me i dea o f wha t t o l ook f or a re s pend ing more t ime a c tua ll y s earch ing f or a nc ien t b oa ts i n t he l ike l ier p laces o n t he f oreshores a nd b anks o f l akes , e stuar ies a nd r ivers a nd Iam c on f iden t t ha t t he o pportun it ies f or s e lec t ion o f ma ter ia l f or e xcavat ion w il l b e g rea t ly i ncreased . l ess , t he r ecord o f r ecen t ma jor f i nds i s n ot u n i mpress ive :1 958
G uy 's Hosp i ta l -
Romano-Br it ish
1 962 1 963 1 965-7
B lack fr iars Nor th Ferr iby 3 S u t ton Hoo - ( re-excavat ion ) -
Ro mano-Br it ish Bronze Age S axon
1 970
Graveney -
L a te S axon
1 974
Br igg Ra f t ( re-excava t ion ) -
L a te Bronze Age
6
N ever the-
T o t hese may b e a dded o ver a s core o f d ugou ts i n t he l as t t wen tyf ive y ears a nd a n u mber o f f ragmen ts o f med ieva l v esse ls s uch a s t hose f ro m L ondon , Dub l in , e tc . I ti s b y n ow a c o m monp lace t ha t t he mos t f or m idab le r isk t ha t a t tends a s urv iv ing r e l ic o f p er ishab le ma ter ia l l i ke a n a nc ien t b oa t i s d iscovery i t se l f . I ti s a measure o f t he i mprove men t i n c ircu mstances i n t h is c oun try t ha t t he mos t r ecen t e xcava t ion i n t he l i st a bove , i nciden ta l ly i n ac on tro l lab le d ry l and s i tua t ion , was c arr ied o u t w i thou t u ndue p ressure o f t ime a nd l ed t o c o mp le te r ecovery o f t he r e ma ins f or c onserva t ion .
T he e x istence o f a n e s tab l ish men t ,
a s a t G reenw ich , p roper ly s ta f fed a nd e qu ipped h owever i s , w i th in t he r es ources a va i lab le , n o more t han a b eg inn ing r a ther t han a s o lu t ion .
T here
r e ma ins t he d anger t ha t b ecause o f i nadequa te a ssess men t o f p r ior i t ies , o r as er ies o f emergenc ies c rea ted b y a cc iden ta l d iscover ies , e ven t he most amb i t ious f aci l i t ies c ou ld e asi ly b e o verwhe l med .
I ti s t he more i mpor tan t ,
t here fore , t ha t work s hou ld b e p lanned a nd p rogra m mes f or r esearch c ont ro l led .
A s i n o ther b ranches o f a rchaeo logy , i ti s a ma t ter o f a sk ing t he
r igh t q ues t ions a nd u sing t he t oo ls o f e xcava t ion o r o ther t ypes o f r esearch t o p roduce t he a nswers. I n t h is way c o mpro m ise , s hor t c u ts a nd r isks w i l l b e r educed a nd p urpose fu l a nd r e levan t i n for ma t ion b e p roduced . It here fore c onc lude t h is p aper b y a t te mp t ing a n a na lys is o f t he p ossib le c onsequences o f ad iscovery whe ther i tb e b y a cc iden t o r d esign .
T he s teps
a s Is ee t he m a re t hese :I .
F ind a nd e nsure r epor t t o ab ody q ua li f ied t o a ssess t he i mpor tance o f t he f ind .
2 .
I den ti fy a nd " po l ice" f or p ro tec t ion .
3 .
R ecord
4 .
D e ter m ine i mpor tance a nd e s tab l ish p r ior i ty f or a pp l ica t ion o f r esources f or f u ture r eseach b y a n o rgan isa t ion f u l ly c apab le o f t he r esponsib i l ty .
5 .
E xcava te
a nd/or i nvest iga te - a ga in b y ap roper ly q ua l i f ied t ea m .
6 .
R ecover i n t o ta l o r p ar t ia l ly f or - e xa m ina t ion ,
a na lysis ,
r esearch
- c onserva t ion - d isp lay 7 .
I n terpre t - o n p aper - w i th t he h e lp o f r econs truct ion - b y means o f p roduc t ion o f ar ep l ica - b y p rac t ica l t r ia l
8 .
P ub l ish r epor ts a t a l l a ppropr ia te s tages.
A me thod ica l a pproach o f t h is k ind may i nvo lve n ega t ive a s we l l a s p osit ive d ec isions a nd i ti s e spec ia l ly i mpor tan t t ha t ac onsc ious d ec ision NOT t o p roceed s hou ld b e p roper ly s uppor ted a nd f u l ly u nderstood .
I nac t iv i ty f or
g ood r easons must b e a cco mpan ied b y a dequa te f ac i l i t ies f or p ro tec t ion . 7
A c t iv i ty must a t a l l t imes b e b ased o n a wareness o f wha t i s i nvo lved i n a ccess t o r esources : h u man ,
ma ter ia l a nd f inanc ia l .
Our S y mposium p rogra m me i s d es igned t o i l lu m ina te a n umber o f a spec ts o f a n a c t ion p rogra m me s uch a s t ha t o u t l ined a nd , i n p ar t icu lar , t hose wh ich may h ave r ece ived t oo l i t t le a t ten t ion i n t he p ast o r i nvo lve n ove l a pproaches . We h ave n o t i ncluded t echn iques o f e xcava t ion wh ich u sua l ly r equ ire t o b e i mprov ised o r d eve loped s pec ia l ly a ccord ing t o c ircumstances . t ha t we s ha l l h ave a f ru i t fu l a nd s t i mu la t ing s ymposiu m .
8
Ib e l ieve
3 .
A GLOSSARY OF BOAT ARCHAEOLOGY TERMS J . E. G . McKee S u m mary
Wi th s a i lors c om ing f resh t o a rchaeo logy a nd a rchaeo log ists f irst g o ing t o s ea , words a re n o t g o ing t o mean t he s a me t h ing t o t he r eader a s t he wr i ter i n tended .
Whereas a rchaeo log ica l t er ms
h ave , f or t he mos t p ar t , b een c lose ly d e f ined a nd s tandard ised , we l ack a n a u thora t ive E ng lish n au t ica l d ic t ionary . P ast a t te mp ts t o c o mp i le a c o mprehensive work h ave f a i led d ue t o a im ing h igher t han t he a va i lab le s uppor t . f unds , wh ich a re h arder t han e ver t o f ind .
T o-day t h is means I ns tead a s hor ter a nd
more s e lec t ive g lossary wou ld p rove more p rac t ica l a nd a t ta inab le . T he p aper s uggests i t s s cope i n o u t l ine .
On ly h ead ings c over ing
av esse l 's p urpose , h er s hape , c onstruc t ion , c o mponen ts , p ropu lsion a nd t he r e la t ive p osi t ion o f t hese i t e ms a re e nv isaged .
P re ference
i s g iven t o t he s i mp ler u se fu l words wh ich c o mb ine we l l t o d escr ibe more c o mp lex o nes a nd s o a vo id t er ms o f l im i ted u se . D e f in i t ions wh ich l end t he mse lves t o u nderstand ing a nd t ransla t ion a re d esirab le .
T he n eed f or a mu l t il ingua l v ers ion i s a dm i t ted ,
b u t a s b e ing s econdary t o ac oun tries u nh indered p rogress i n h er o wn t ongue . C en tra l c on tro l i s e ssen t ia l i ft he work i s t o b e c o mp le ted a nd p ub l ished .
I n a dd i t ion t o t h is , s uch a n o rgan isa t ion wou ld b e a b le
t o s e t t le t er m ino log ica l p rob le ms a nd p ave t he way f or t he more c o mprehensive d ic t ionary .
T he c hes tnu t , wh ich g ives t he a dv ice t o t hose c onsider ing marr iage a s , " Don ' t" ,
p robab ly a lso a pp l ies t o t hose a bou t t o s tar t ag lossary .
c ases , h owever , i t may b e t he o n ly way o f g e t t ing a d esired g oa l .
I n b o th Wha t i s
t h is g oa l ? I n t he c ase o f t he g lossary , i ti s t he n eed t o u se words t ha t mean t he s a me t o t he r eader a s t he wr i ter .
T h is i s a s much a p rerequ isi te f or a
s c ien t ist a s marr iage l i nes f or a p ruden t ma iden . P roposa ls f or i nnova t ions must a nswer t he c ha l lenge , "Wha t i s wrong w i th wha t we 've g o t?"
T here i s n o t as i mp le a nswer , i n t ha t p ar t o f wha t
we 've g o t maybe g ood e nough a lready .
I ts ee ms t ha t aG lossary o f T er ms
f or N au t ica l Archaeo logy wou ld h ave t wo a spec ts .
T ha t i s t he p ar t d ea l ing
w i th t he a rchaeo log ica l t er ms u sed when e xa m in ing , r ecord ing , e va lua t ing a nd c onserv ing a v esse l 's r e ma ins ; a nd t hen t he n au t ica l p ar t d escr ib ing t he t er ms u sed a bou t t he v esse l h erse l f .
T hese t wo a spec ts h ave o n ly b een
b rough t t oge ther r ecen t ly ; a nd t h ink ing a bou t t he e f fec t o f t h is i s , t o s o me 9
e x ten t , t he p urpose o f t h is s y mposiu m .
Wh i le a rchaeo logy h as h ad i t s o wn
t er m ino logy f or s o me t ime , t he a dd i t ion o f an au t ica l s ide h as modi f ied o ld t echn iques a nd i nven ted n ew o nes . s e ldo m e xac t , c onstan t ly c hang ing .
S ea men h ave a lways h ad t he ir o wn a rgo t , Wh i le o ne s hou ld h ave s o me s y mpa thy
f or t he g ru mb les o f l and a rchaeo log is ts , Imust u rge t he n au t ica l a rchaeo log ist t o mas ter t he c orrec t u se o f s ea-words. May Id ea l w i th t he a rchaeo log ica l p ar t f irs t?
I ts ee ms t o me t ha t t hese
t er ms h ave a lready b een we l l d e f ined , a nd i fo ne h as h ad a nd b ene f i t ted f ro m ac lassica l e duca t ion , t hey a re e asy t o u se a nd u nderstand .
T he f ew n ew
t er ms c an b e i n tegra ted a s t hey a ppear , a nd when N au t ica l Archaeo logy h as s e t t led d own , t here w i l l b e ac ase f or a n a rchaeo log ica l s ec t ion .
C er tain ly ,
t h is wou ld b ene f i t web-foo ted n ewco mers , l i ke myse l f , who u ses f our l e t ter words l i k eboa t " r a ther t han f ive s y l lab le o nes l i ke ' archaeo logy ' .
A s t here
a re many p resen t we l l e ndowed t o c o m men t o n t he n eed f or a n a rchaeo log ica l s ec t ion , Ih ope t ha t t hey w i l l d o s o i n t he d iscussion p er iod . Iwou ld n ow l i ke t o s i t d own a nd l e t y ou d iscuss t he p ar t o f t he g lossary t o d o w i th v esse ls.
Bu t , If ee l i ti s u p t o me t o p rov ide a f ew v ic t i ms f or y ou
l i ons t o t ear a par t .
Wha t n au t ica l g lossar ies h ave we g o t?
T hough i n t he
p as t t here h ave b een s o me e xce l len t n au t ica l d ic t ionar ies , wh ich g ive v a luab le mean ings f or t he t er ms t hen u sed , o ur n eeds .
Ik now o f n o c urren t E ng l ish work t ha t mee ts
C ap ta in P aasch 's F ro m K ee l t o T ruck
( 4 th E d . 1 908 ) , i n E ng l ish ,
French a nd G er man i s i l lustra ted , b u t f a l ls s hor t a s i ti s ma in ly a bou t c o mmerce o ver a n arrow p er iod .
T he s a me s or t o f c r i t ic is m c an b e l eve l led a t t he
p ure ly m i l i tary a spec t o f t he 1 937 S ea mansh ip Manua l , wh ich i s a dm irab le , o nce t he d e f in i t ions s ca t tered t hroughou t t he t ex t h ave b een e xcava ted . N au t ica l D ic t ionary ( Brown , S on a nd F erguson ) ,
L ay ton 's
s t i l l i n p r in t a nd n o t c os t ly ,
a vo ids b ias a s i t was wr i t ten b y a n o f f icer o f t he Merchan t N avy b u t was r ev ised b y o ne f ro m t he R oya l N avy .
I ti ncludes many o f t he o lder t er ms a nd
i s ag ood work-a-day r e ference . A s he l f f u l l o f d ic t ionar ies may we l l h o ld t he c orrec t d e f in i t ion , b u t t h is c a l ls f or i nd iv idua l d ecis ions a nd r isk o f c on fusing t he r eader .
T he C onc ise
Ox ford D ic t ionary , a much a bbrev ia ted v ers ion o f t he N ew E ng l ish D ic t ionary , o f fers r e l iab le d e f in i t ions o f many n au t ica l t er ms , b u t t here i s t oo l i t t le e xp lana t ion . T o g e t t h is o ne must t urn t o t he N ew Eng l ish D ic t ionary , wh ich i s ab i t l i ke s ign ing o n t he L ondon P h i lhar mon ic Orchestra t o p lay t he s ea c han t ies o n b oard a T ha mes B arge . F ee l ing t he n eed t o r egu la te my o wn u sage , Ih ave b een a sse mb l ing a c ard i ndex o f b oa tbu i ld ing t er ms ; o ver t hree t housand o f t he m a nd s t i l l g rowi ng f ast .
I ti s u n l ike ly t ha t a ny p ersona l g lossary c an b e c o mp le ted o r u sed
i fi t was ; n o t b ecause t he ma ter ia l i s a t f au l t , b u t b ecause i tw i l l r epresen t t oo n arrow a p recoccupa t ion f or g enera l p urposes . I f Iam c onv inced t ha t n au t ica l a rchaeo log ists wou ld b ene f i t f ro m a n a u thora t ive g lossary o f t er ms , i ti s d ue t o t he f requency w i th wh ich Ih ave w ished t here was o ne . u sage .
A ny s pec ia l isa t ion t ends t o w eaken o nes c on tac t w i th n or ma l
T h is d oesn ' t ma t ter u n t i l o ne p icks u p ap en o r ab ook .
T h is i s t he
mo men t o ne i s a t al oss f or a word o r n eeds c lar i f ica t ion o f a mean ing .
F or
me , ag lossary o f n au t ica l t er ms wou ld n eed t o c over d escr ip t ions o f e very a spec t o f s h ipp ing o f a l l t rad i t ions a nd a ges , h ow t hey were b u i l t f or , a nd 1 0
o pera ted i n , t he p ursu i t o f war a nd t rade , f i sh a nd t ranspor t , p o mp a nd p leasure .
S uch a g lossary c an e i ther b e c onc ise w i th c are fu l ly c hosen a d-
a p tab le t er ms a ccura te ly d e f ined , o r i th as t o b e v ery l arge t o b e t ru ly d e f in i t ive . One o f t he d ec lared a i ms a t t he f ounda t ion o f t he S oc ie ty f or N au t ica l R eseach was " to c o mp i le a c o mp le te a nd s cho lar ly e ncyc lopaed ia o r d ic t iona ry" ( Ru le 1 1 , 3 .) . We k now f ro m L .G . C arr L augh ton 's a r t ic le i n t he Mar iner 's M irror ( Vo l . 1 0 , p . 2 99 ) , a nd t he i n troduct ion b y G .P.B. Na ish t o i t s r epr in t ( Vo l . 4 4 , p . 1 90 ) ,
t ha t i n s p i te o f t he f ine i n ten t ions a nd p ro found
s cho larsh ip o f ad ed icated f ew , t h is a im h as , t hrough l ack o f h e lpers , y et t o b e r ea l ised .
We c an l earn f ro m t h is t ha t a ny th ing s im i lar c a l ls f or s us-
t a ined e f for t o ver a l ong p er iod. I fi n 1 924 t here were n o t e nough s cho lars w i th i ndependen t means t o c arry t hrough t h is p ro jec t , Id oub t i ft hey c ou ld b e f ound t o-day .
T he o n ly
s ure way t o g e t c on t inu i ty u p t o c o mp le t ion i s t o p ay a c o mpe ten t s ta f f ; b u t wha t i s t he c hance o f f inding f unds f or s uch a n e n terpr ise a t p resen t? i s n o t t o s ay t ha t t he o b jec t ive i s n o t s t i l l d esirab le .
T h is
I t mos t c er ta in ly i s ,
b u t i t migh t b e r ea l ist ic t o s he lve i tf or t he mo men t a nd s e t t o work o n a more c onc ise g lossary o f u se fu l t er ms f or n au t ica l a rchaeo log ists. When a C h ina man l earns t o wr i te , h e h as t o me mor ise a nother i deograph f or e very n ew word h e u ses .
T h is a pparen t ly ' I nsur moun tab le t ask was s i mp-
l i f ied when t he s cho lars d rew u p al i st , k nown a s t he f irst h undred c harac ters . T hese were s o f unda men ta l o r c o m mon , t ha t r epe t i t ion f ixed t he m i n t he mind . T here t hen f o l lowed t he s econd a nd t h ird h undred c harac ters a nd s o o n u n t i l ; Is uppose , t he t h irst f or a ny more s cho larsh ip was s laked .
Is uggest t ha t a
wor thwh i le c onc ise g lossary c ou ld b e p u t t oge ther i n an o t d issi m i lar manner . D iv ided b e tween a g roup o f workers , t hree o r f our h undred words wou ld g ive u s a work ing n uc leus , w i thou t c rea t ing t oo g rea t ab urden .
T h is s hou ld
a t l east i nd ica te h ow much l arger t he c oncise g lossary migh t h ave t o b e , a nd wha t s or t o f a nd h ow much work was s t i l l n eeded .
Wh i le s ing le t er ms c an
b e d e f ined b y i nd iv idua l e f for t , af oca l o rgan w i l l b e n eeded t o a ppor t ion work , r eso lve d i f f icu l t ies a nd i n d ue c ourse , e d i t a nd p ub l ish t he g lossary. Wi thou t s o me f or m o f c en tra l c on tro l i ti s u n l ike ly t ha t f ina l i ty wou ld b e r eached , a nd y our v iews o n t he n a ture o f t h is w i l l b e s ough t l a ter . T o s t i mu la te i deas , i ti s s uggested t ha t ac onc ise g lossary o f t er ms s hou ld i nc lude t er ms u nder t hese h ead ings :P urpose o f v esse l , c og , f i f ie .
words s uch a s c oaster ,
t ender ,
D escr ip t ion o f f or m a nd a b i l i ty , s uch a s d ep th , c l ipper , a rden t . Bu i ld ing p rocesses a nd t oo ls , s uch a s c lench
r a ther t han t hose l i ke
s tab i l i ty ,
r a ther t han
a uger r a ther t han c arve l ,
f abr ica te . P ar ts o f av esse l ,
s uch a s d eadwood ,
c oun ter r a ther t han s korve l ,
s p irke t t ing . P ropu lsion me thods a nd g ear ,
s uch a s c lew a nd t ho lep in
1 1
r a ther t han
r a f fee
t hran i te .
P osi t ion i nside o r i n r e la t ion t o av esse l , s uch a s a thwar t , a stern r a ther t han w indward , s uper ior . T h is l i st i s f ar f ro m e xhaust ive a s y e t .
I tc ou ld e asi ly b e e x tended i n a
n u mber o f ways ; s ay b y t he i nc lusion o f t he t er ms u sed i n c o m merce .
Bu t ,
my p re ference wou ld b e f or t he min i mu m n u mber o f t er ms c onsisten t w i th s ound u sage .
T here i s n o th ing o b jec t ionab le a bout t he w ords e xc luded a bove ,
o ther t han t hey a re s u f f ic ien t ly s pec ia lised t ha t t hey o ugh t t o b e p u t i n a more c o mprehensive work t han t h is i s mean t t o b e . T he d ef in i t ion o f e ach t er m s e lec ted f or i nc lusion wou ld n eed t o b e s ubs tan t ia ted f ro m r e l iab le s ources , a nd t here wou ld h ave t o b e v ery g ood r easons f or d epar t ing f ro m t he g enera l s ense g iven i n t he N ew E ng l ish D ic t ionary . F or c lar i ty d escr ip t ions s hou ld u se o ther t han n au t ica l t er ms whenever i ti s p oss ib le , a nd p re ference g iven t o t er ms t ha t c o mb ine we l l i n d escr ip t ions o ver t hose whose u se i s l im i ted .
I ft he s cope o f t he g lossary i s t o b e c o mp le te
i n i t se l f , t h is w i l l mean t he i nc lusion o f many q u i te c o m mon t er ms.
T i me
a nd a ga in , i ti s t hese words t ha t a re mos t o f ten m isused a nd misunders tood a s t hey a re t he h ardest t o d e f ine . S ea men a re i nconsisten t a nd t end t o u se t er ms s lack ly , r e ly ing o n c on tex t t o c onvey mean ing ; b u t t h is i s n o t g ood e nough f or wr i t ten work . T ake t he word g unwa le . Or ig ina l ly t h is mean t t he r ange o f t h icker s trakes b e low t he g unpor ts ; b u t ac en tury a go i th ad c o me t o mean t he p lank wh ich c overed t he h eads o f t he t imbers b e tween t he d r i f ts , o r where t he s heer r ises t o ah igher l ine .
I n ab oa t , t he t er m w as u sed f or t he s heer s trake , t he i nwa le , t he r ubber
o r e ven t he c app ing i fi t was s turdy e nough .
T urn ing t o t he C oncise Ox ford
D ic t ionary o ne f inds , " The u pper e dge o f as h ip 's o r b oa t 's s ide" .
S o i ts ee ms
t ha t , o ver t he y ears , t he g unwa le i s n o l onger p ar t o f av esse l , b u t i s n ow a p osi t ion o n i t .
T here a re o ther c o m mon t er ms l i ke C h ine a nd Kee lson wh ich
w i l l n eed c are fu l u se u n t i l we h ave p rec ise d e f in i t ion f or t he m . S evera l t er ms may b e u sed f or a s ing le i t em ; s trake
s troke a nd s treak
b e ing e xa mp les . I fi n e ach c ase t he i t e m mean t i s i den t ica l , o ne wou ld e xp ec t t he c o m mones t f or m t o b e c hosen a s t he s tandard f or wr i t ten u se a nd t ransl a t ion .
T he o thers b eco me d ia lec t ic v ar ia t ions , wh ich s hou ld b e r ecorded i n
s o me more d e ta i led g lossary .
On t he o ther h and , s o me v ar ia t ions may r e-
l a te t o a n a c tua l d i f ference i n f or m o r a c t , f or i nstance ; b u l l c log .
c opp ,
a nd
T he p rob le m h ere i s t o d ec ide whe ther a c o l lec t ive t er m h as t o b e
f ound f or t hese t hree s ing le t ho lep in o ars o r i fa l l t he t er ms a re t o b e i nc luded . T hough t s hou ld b e g iven t o t he n eed f or a mu l t il ingua l g lossary d eve loped i n terna t iona l ly .
G iven t he c o m mand o f l anguages , i ti s h ard t o t h ink o f ab e t ter
o ccupa t ion ; b u t t o s tar t w i th , k eep ing i n s tep migh t h inder r a ther t han h e lp . I fc oun tr ies a re f ree t o make t he ir o wn s peed , wh i le t hey f o l low a c o m mon p a t tern , If ee l s ure t hey w i l l b e a b le t o a l ign t he ir e f for ts a t s o me l a ter d a te . T hough t he i dea o f ac o mprehens ive g lossary was p u t o n as he l f e ar l ier , i t was b y n o means a bandoned .
Much c an b e d one t o p repare f or i t , wh i le
h e lp ing n au t ica l a rchaeo log ists a t t he s a me t ime .
A s a n i m med ia te s tep ,
ab ib l iography o f s ources o f n au t ica l t er ms i s s uggested. 1 2
A r ev is ion o f
t he l i sts o f d ic t ionar ies g iven i n t he f irst t wo v o lu mes o f t he Mar iner 's M irror c ou ld b e t he way t o s tar t , i n E ng l ish a nd F rench a nyway .
T h is
Museu m 's S e lec t B ib l iography f or t he D eve lop men t o f t he B oa t i s a no ther s tep i n t he s a me d irec t ion , n o t o n ly f or i t s v a luab le c on ten ts b u t f or t he c lear i nd ica t ion t ha t t h is i s n o sma l l t ask .
S o me o f t he s ources may b e h ard t o l oca te ,
a nd i fr are , a ccess t o t he m may n o t b e e asy . r esearch , i tc an s low d own p rogress.
Wh i le t h is s hou ld n o t d iscourage
I t wou ld h e lp t here fore i fe ach s ource
l i s ted g ave a dv ice o n h ow o r where i t migh t b e s een . T o s um u p , h ere a re s o me p o in ts y ou migh t c are t o d iscuss. F irst ly , i s aG lossary o f T er ms a r equ ire men t? c onc ise a nd a va ilab le s oon?
I fs o , s hou ld i tb e :-
o r
c o mprehens ive , t ak ing l onger?
o r b oth?
I n a ny c ase , s hou ld a rchaeo log ica l t er ms b e i nc luded? a nd i s al i st o f s ources o f n au t ica l t er ms n eeded? F ina l ly , wha t s or t o f o rgan isa t ion d o y ou e nv isage t o f or mu la te a nd c arry o u t d ec is ions? T hough y ou may b e r eady t o d iscuss t hese p o in ts , y ou may n o t b e r eady t o make d ec isions r igh t a way .
I ft here i s s u f f icien t mer i t i n a ny o f t hese
p roposa ls , i s t h is s o me th ing y ou wou ld l i ke t o s ee t aken f ur ther?
1 3
D ISCUSS ION Mc Gra i l :
We n eed a n a greed work ing g lossary d e f in ing t he t er ms we n ow u se , wh ich may s ubsequen t ly b e e xpanded i n to t he g rand d ict ionary . T here i s s o much t o d o i n b oa t a rchaeo logy t ha t we n eed l and a rchaeo log is ts w i th a n i n terest i n b oa ts t o work w i th u s a nd n o t t o b e f r igh tened b y o ur t echn ica l t er ms .
I
s uggest t here fore t ha t we u se a ny c o m mon words t ha t c an b e u sed w i thou t l oss o f p rec ision .
I fc ove i s s ynony mous w i th
g roove l e t u s u se g roove , b ecause we w i l l l ose n o th ing , t he l and a rchaeo log is t w i l l g a in a l o t , a nd we w i l l g a in b y h is a c tive i n terst . Wo l le :
Ag lossary i s n eeded b y b o th s ea man a nd s cho lar .
Madden :
T h is g lossary s hou ld b e f u l ly i l lus tra ted .
Du P la t T ay lor :
L and a rchaeo log is ts o f ten misuse t echn ica l t er ms f or s ay a rch i tec ture a s we l l a s t he s ea , a nd a g lossary wou ld o verc o me t h is p rob le m .
Wr igh t :
F or ma ter ia l n o t c overed b y a ccep ted n ava l a rch i tec tura l t er m ino logy we d o n eed " new s peak" - t ha t i s , we n eed t o i n troduce n ew t er ms.
Greenh i l l :
T he t rad ing k e tch S ha mrock ,
wh ich t h is Museu m a nd t he
N a t iona l T rust a re r es tor ing , i s p erhaps c loser i n s truc ture a t t he b o t to m-apar t f ro m t he f ac t t ha t s he i s n o t e dgejo inedt o t he F err iby b oa ts t han t o most V ic tor ian s a i l ing s h ips. T h is i s a n e xa mp le o f why we n eed t he c lar i f ica t ion t ha t Mr . Wr igh t men t ioned , s o t ha t we c an d escr ibe t he c onstruct i on o f t hese b oa ts w i thou t amb igu i ty . C hr is tensen :
Ir eco m mend wha t h as b een d one i n N orway : p ick o u t a sma l l a nd we l l d e f ined a rea , o ne c ra f t , o ne t ype o f s h ip , t he w ork o f o ne c ra f ts mah , a nd d e f ine t he t er ms u sed t here .
Greenh i l l :
One o f t he main p rob le ms i n t h is c oun try w i l l b e d e ter m in ing t he p re ferred word f or d e f in i t ion , when y ou h ave g o t s uch t re mendous d ia lec t v ar ia t ion i n t he r eg ions .
E d i tor ia l N o te .
T h is t op ic was f ur ther c onsidered i n t he d iscussion a f ter B asi l G reenh i l l 's S u m mary .
1 4
4 .
DEGRADAT ION OF WOOD J . F. L evy S u m mary
T he a spec t o f d egrade o f wood o f mos t c oncern t o t he a rchaeo log ist i s c aused b y b ac ter ia a nd f ung i .
T hese o rgan is ms d egrade
wood w i thou t , a pparen t ly , a l ter ing t he s hape , s ize a nd o u t l ine o f t he o b jec t s o l ong a s i tr e ma ins we t .
T he midd le l ayer o f t he s econdary
c e l l wa l l i s d es troyed a nd w i th i tt he s treng th o f t he wood , wh ich i s n o l onger a b le t o w i thstand t he i n terna l s tresses s e t u p a s i td r ies o u t . T h is c an l ead t o s p l i t t ing , d istor t ion a nd a c hange o f s hape wh ich c an r ender t he o b jec t a l mos t u nrecogn isab le .
T he a c t iv i ty o f b ac ter ia
a nd f ung i a nd t he ir e f fec t o n t he wood c e l l wa l ls i s d escr ibed .
Wood c an b e d egraded i n many ways .
F ire , c he m ica ls , mechan ica l wear
a nd t ear , a nd e xposure t o wea ther ing o u t o f d oors c an a l l b r ing a bou t t he p ar t ia l o r c o mp le te b reakdown o f t he ma ter ia l .
T he mos t w idespread d egrade i s ,
h owever , c aused b y t he b io log ica l a genc ies wh ich n or ma l ly f or m p ar t o f t he p rocess whereby p lan t a nd a n i ma l r e ma ins a re b roken d own t o t he ir c onst it uen t p ar ts i n t he s o i l f or t he r ecyc l ing o f t hese ma ter ia ls i n to n ew p lan ts a nd s ubsequen t ly a n i ma ls .
T hese b io log ica l a genc ies t ake many f or ms : a n i ma l ,
f ro m r oden ts a nd woodpeckers t o mar ine b orers ; i nsec ts , i nc lud ing t he, t er m i tes ; a nd p lan ts , p ar t icu lar ly t he f ung i a nd b ac ter ia . F ro m t he a rchaeo log is t 's p o in t o f v iew t he d egrade c aused b y a n i ma ls i s s u f f ic ien t ly l arge a nd o bv ious t o b e s een , a nd t he d isf igure men t c aused may b e s o g rea t a s t o r ender t he o b jec t o f d oub t fu l v a lue f or c onserva t ion .
E ven
t he sma l les t wood-bor ing b ee t les make a g a l lery whose d ia me ter i s many t imes g rea ter t han a l l b u t t he l argest o f t he wood c e l ls. T he f ung i a nd b ac ter ia , o n t he o ther h and , c an c au se c onsiderab le d eg rade w i thou t a pparen t ly a l ter ing t he s hape , s ize a nd o u t l ine o f t he o b jec t s o l ong a s i tr e ma ins we t .
I ti s o n ly when t he o b jec t b eg ins t o d ry o u t t ha t d ry-
i ng s tresses c an c ause s p l i t ting , d is tor t ion a nd a c hange o f s hape , wh ich c an r ender t he o b jec t a l mos t u nrecogn isab le . T h is p aper w i l l , t here fore , o n ly b e c oncerned w i th t he t ype o f d egrada t ion c c aused b y f ung i a nd b ac ter ia ; t he ir e f fec t o n t he wood ; t he i mpor tance o f t he c ond i t ions o f b ur ia l ; t he p ar t o r p ar ts o f t he wood d estroyed ; a nd t he r easons f or t he d istor t ion o n d ry ing . Wood a s a ma ter ia l T he ma ter ia l , wood , c onsists o f al im i ted n u mber o f b asic u n i ts o r c e l ls wh ich a re f or med i n ar egu lar manner a s t he t ree g rows. Most o f t he t imber 1 5
F ig . 4 .1
S cann ing e lec tron m icrograph o f Oak
u ercus s p .) s how ing t he
wood c u t i n t he t ransverse , t angen t ia l l ong itud ina l a nd r ad ia l l ong itud ina l p lanes ( x 1 . 00 ).
F ig . 4 .2
S .E. M . p icture o f S co ts P ine ( P inus s y lvestr is ) s how ing t he wood c ut i n t he t ransverse , t angen t ia l l ong itud ina l a nd r ad ia l l ong itud ina l p lanes ( x 9 0 ).
o f c o m merce h as b een c u t f ro m t he s te m o f af orest t ree . T he a rrange men t o f t he c e l ls w i th in t he t imber w i l l r e f lec t t he t hreefo ld p urpose o f i t s f or mat ion , ( a ) mechan ica l s treng th t o s uppor t t he we igh t o f t he b ranches a nd l eaves a nd t o r esist p er manen t d a mage when t he w ind b lows ,
( b ) as yste m o f t ubes
o r p ipes t o a l low wa ter f ro m t he s o i l t o p ass f ro m t he r oo ts o f t he l i v ing t ree t o t he l eaves a nd ( c ) as ys te m t o e nab le t he l a tera l t ranspor t o f wa ter a nd ma ter ia ls t o t ake p lace a nd t o s tore r eserves o f f ood t o s uppor t g row th a nd d eve lop men t wh i lst t he b uds a re b reak ing a nd b e fore t he l eaves a re f u l ly o pen . T he c e l ls a re c harac ter ised b y t he p ossession o f ac e l l wa l l c onsisting o f c e l lu lose , h em icel lu loses a nd l ign in w ith o ther ma ter ia ls ( known a s e x tract ives ) a dded i n v ary ing amoun ts a t al a ter s tage o f d eve lop men t . C e l lu lose i s t he ma in s truc tura l c o mponen t , t he l ong c ha in mo lecu les b eco m ing a ggrega ted t oge ther t o f or m l ong p ar t-crysta l l ine s truc tures k nown a s microf ibr i ls . T hese micro f ibr i ls a re s e t d own i n c lose ly p acked h e l ices , s o mewha t a na logous t o t he w ind ing o f ah o l low b a l l o f s tr ing , b u t e ach h e l ix i s c rosslinked w i th i t s n e ighbours. T he micro f ibr i l i s t hough t t o c on ta in h em ice l lu lose i n i t s o u ter r eg ions a nd t hese h em ice l lu lose mo lecu les may , i n s o me way , a c t a s ak ey b e tween t he s truc tura l c e l lu lose a nd t he amorphous l ign in whose p rec ise p os i t ion a nd f unc t ion i s n o t e n t ire ly c lear , b u t may b e r egarded a s p ar t o f t he ma tr ix o f t he wa l l .
T he o r ien ta t ion o f t he microf ibr i ls w i th r espec t t o t he l ong a x is o f
t he c e l l h as a n i mpor tan t b ear ing o n t he s treng th p roper t ies o f t ha t c e l l , wh ich w i l l d i f fer a ccord ing t o whe ther t he s tress a c ts a long o r a cross t he l ong a x is o f t he c e l l .
Wood i s t hus a n a n iso trop ic ma ter ia l , t ha t i s t o s ay , i t s p roper-
t ies w i l l v ary a ccord ing t o t he o r ien ta t ion o f t he a x is o f t he c e l l o r , i n o ther words , t he g ra in d irec t ion . S ince t he s treng th a nd p roper t ies o f wood d epend o n t he o rgan isa t ion o f t he c e l l wa l l , i tf o l lows t ha t t he t h ickness o f t he wa l l a nd t he p ropor t ion o f a u n i t v o lu me o f wood o ccup ied b y c e l l wa l l ma ter ia l w i l l h ave a marked e f fec t o n t he p roper t ies o f wood .
B a lsa c an we igh a s l i t t le a s 1 0 l b/ f t3 ( 160 k g/ m 3 )
when a ir d rx , wh i lst l ignum v i tae i s e igh t t imes a s h eavy a t 8 4 l b/ f t3 ( 1250 Kg/ m `3) .
T he f or mer h as t h in c e l l wa l ls a nd much a ir s pace p er u n i t
v o lume o f wood , wh i lst t he l a t ter h as v ery t h ick wa l ls a nd v ery l i t t le a ir s pace p er u n i t v o lume . Fung i a nd b ac ter ia a c t o n t he c o mponen ts o f t he c e l l wa l ls. S o me a t tack a nd d es troy a l l t he c o mponen ts , o thers o n ly a t tack o ne o r t wo o f t he c o mponen ts , wh i ls t o thers o n ly d es troy a p ar t icu lar p ar t o f t he wa l l i n ap ar t icu lar way , Bravery ( 1971 a nd 1 975 ) , ( 1974 ) ,
K irk ( 1975 ) ,
L iese a nd G reaves ( 1975 ) ,
L evy
L evy , Mi l lbank , Dwyer a nd B a ines ( 1974 ) .
T ypes o f f ung i a nd b ac ter ia T he f ung i a ssocia ted w i th d egrade o f wood may b e s epara ted i n to f ive g roups . Mou lds S ta iners S o f t r o ts B rown r o ts Wh i te r o ts
1 7
Mou lds f eed o n t he c arbohydra tes , f a ts a nd p ro te ins a nd g enera l d e tr i tus e xposed when c e l ls a re c u t o pen a s wood i s s awn o r p laned .
T hey r are ly , i f
e ver , p ene tra te b enea th t he s ur face , a nd t hen o n ly t hrough h o les i n t he c e l l wa l ls s ince t hey d o n o t n or ma l ly p ossess t he e nzy me s yste ms c apab le o f b reak ing d own t he wa l l ma ter ia l .
T hey s erve t o i nd ica te t ha t t he wood i s i n
as u i tab le c ond i t ion t o s uppor t f unga l a t tack . S ta iners a re t hose f ung i wh ich c o lon ise t he r ay c e l ls i n s apwood , f eed ing o n t he s tored r eserve f ood ma ter ia ls l a id d own b y t he t ree .
T he f ine s trands
( or h yphae ) o f t he f ung i b eco me p igmen ted a t ma tur i ty a nd t h is d ark c o lour c an d isf igure t he s apwood o f mos t s pec ies o f t imber . I n s o me s of twood s peci es t he b r igh t b lue d isco loura t ion g ives r ise t o t he t er m " b lue s tain" .
I n wood
t hey c ause v ery l i t t le s truc tura l d egrade b u t a re a b le t o p ene tra te t hrough c e l l wa l ls f ro m t he l u men o f o ne c e l l t o t he l u men o f t he n ex t , s o me t i mes c rossing many c e l ls .
T he h ypha o n r each ing t he c e l l wa l l b u lges a t t he t ip a nd p ene-
t ra tes t hrough t he wa l l , w i th a much r educed d ia me ter t o emerge i n to t he l u men o f t he n ex t c e l l where t he h ypha a ssumes i t s n or ma l s ize .
T h is s trange ,
c harac ter is t ic , b u t l arge ly u nexp la ined b ehav iour , h as g iven r ise t o much s pecu la t ion , a nd may we l l b e e f fec ted p ar t ly b y l oca l ised e nzy me a c tion a nd p ar t ly b y s o me s or t o f mechan ica l means . T he t hree t ypes o f r o t a l l c ause d egrade o f wood b y d es troy ing s o me o r a l l o f t he c e l l wa l l .
T he e nd p o in t i n e ach c ase i s g rea t ly r educed s treng th
p roper t ies a nd c o l lapse o f t he wood s truc ture .
T he d if ferences i n micro-
morpho logy h ave b een we l l i l lustra ted b y B ravery ( 1 971 ) . T he s o f t r o t f ung i p ene tra te i n to t he wa l l i n a manner s o mewha t r ese mb ling t he s ta iners. H owever , i ns tead o f p ene tra t ing th rough t he wa l l t hey o n ly g o p ar t o f t he way a nd i n t he t h ickest l ayer o f t he wa l l ( known a s t he midd le l ayer o f t he s econdary wa l l , o r t he S2 l ayer ) t he h ypha a ppears t o t urn a t r igh t a ng les a nd b ranch a t t he b end i n t he o pposi te d irec t ion t o f or m wha t h as b een c a l led t he T -branch .
T he t wo e nds o f t he c ross o f t he T e x tend t he ir
g row th a long t he o r ien ta tion o f t he c e l lu lose micr f ibr i ls i n t h is l ayer o f t he wa l l .
A s t hey g row , t he h ypha b eh ind e xpands i n g ir th a nd e nzy me i s r e-
l eased a long i t s l eng th t o f or m a c av i ty i n t he wa l l r ound t he h ypha w i th p o in ted e nds. A c ha in o f s uch c av i t ies i s f or med , c harac ter ist ica l ly f or m ing a h e l ix w i th in t he wa l l p ara l le l t o t he o r ien ta t ion o f t he h e l ix o f t he c e l lu lose microf ibr i ls .
T he r eason f or c av i ty f or ma t ion i s n o t f u l ly u nders tood , b u t i t
mus t b e d ue t o a n i n terac t ion b e tween t he e nzy me s ys te m o f t he f ungus a nd t he a rrange men ts o f t he c onst i tuen t p ar ts o f t he c e l l wa l l .
The c e l lu lose a nd
h em ice l lu lose c o mponen ts a re d es troyed , b u t t he a c t iv i ty o f t he e nzy mes t owards t he l ign in i s a ma t ter o f s o me s pecu la t ion .
T he s ign i f icance o f t h is
t ype o f wood r o t t ing f ungus h as o n ly b een e stab l ished w i th in t he l ast t wen ty f ive y ears a nd i ti s t he c en tre o f much r esearch a c t iv i ty . T he b rown r o t f ung i a re c apab le o f d estroy ing b o th c e l lu lose c e l lu loses b u t l ign in i s n o t b roken d own , o n ly mod if ied .
a nd h em i-
T he h yphae l i e a long
t he c e l l wa l l i nner s ur face a nd e nzy mes d i f fuse f ro m t he f ungus i n to t he wa l l a nd a ppear t o p er mea te a l l t he wa l l l ayers.
T he r eac t ive c o mponen ts a re
b roken d own a nd t he s o lub le s ugars d i f fuse b ack t o t he h ypha .
T he a c t ion o f
t hese f ung i c an b e f ast a nd d evast ing a nd amongst t he ir n u mber a re many o f t he we l l k nown wood-ro t t ing f ung i , s uch a s D ry R o t ( Serpu la l acry mans ) a nd t he C e l lar F ungas ( Con iophora p u teana ) . 1 8
F ig . 4 .3
S .E. M . p icture o f S co ta P ine ( P inus s y lvestr is ) s how ing t he wood c u t i n t he t ransverse p lane. N o te t he c el ls ( t rache ids ) t o t he r igh t a nd l e f t o f t he p ic ture h ave i n tac t c el l wa l ls.
T he c e l ls i n
t he c en tre h ave b een a c t ive ly a t tacked b y as of t r o t f ungus a nd t he m idd le l ayer ( S2 l ayer ) o f t he c e l l wa l ls a l mos t c omp lete ly d estroyed ( x 7 50 ).
T he wh i te r o t f ung i a t tack a nd d estroy a l l t he wa l l c o mponen ts , b u t t hey d o s o i n a manner d i f feren t f ro m t he o ther t wo wood-ro t t ing f ung i .
T he
b ranched h yphae l i e a long t he c e l l wa l l i nner s ur face a nd t he e nzy mes s ecre ted f ro m t he m e rode a g roove r ound t he m .
T he g roove w idens a nd d eepens a nd t he
wa l l i s s low ly e roded i n i t s e n t ire ty f ro m t he i nner s ur face . T he e f fec t o f b ac ter ia o n wood h as o n ly b een s tud ied t o a ny e x ten t w i th in t he l ast t en y ears .
T hey h ave b een s hown t o i ncrease t he p er meab i l i ty o f l ogs
f loa t ing o r s tored i n wa ter b y d estroying t he t h in me mbranes c over ing t he p i ts i n t he c e l l wa l ls.
T h is a lso o ccurs i n t imber i n g round c on tac t a nd h as t he
e f fec t o f o pen ing u p t he s truc ture t o e nab le f ung i t o p ene tra te i n to t he wood i n d ep th .
I ta lso e nab les g aseous d i ffusion t o t ake p lace a nd may t hus c hange a
r eg ion t ha t was a naerob ic a nd c apab le o f s uppor t ing b ac ter ia l a c t iv i ty ,
i n to
a more a erob ic s i tua t ion a nd c apab le o f s uppor t ing f unga l d ecay . B ac ter ia h ave b een s hown c apab le o f d estroy ing t he wood c e l l wa l l u nder c er ta in c ond i t ions ( u sua l ly o f l ong t er m b ur ia l ) ,
a nd t o c ause a d es truc t ion o f
t he wa l l l ayers s im i lar t o t he e f fec t o f t he s o f t r o t f ung i ( L iese a nd G reaves , 1 974 ) . T hey a re k nown t o b e e ar ly c o lon isers o f wood .
N i trogen f ix ing b ac-
t er ia h ave b een s hown t o p ene tra te i n to wood a nd n i trogen f ixa t ion h as b een d e monstra ted i n wood i n g round c on tac t , i n wood i n wa ter c oo ling t owers a nd i n w indow j o inery .
T hey c lear ly h ave a c onsiderab le p ar t t o p lay i n t he c o m-
p lex o f o rgan is ms c ausing wood d ecay . Wood i n g round c on tac t S o i l i s u sua l ly c onsidered t o b e ar eservo ir o f wa ter a nd i ti s c er ta in ly a r eservo ir o f micro-organ is ms .
Wood l y ing o n t he s o i l s ur face o r b ur ied i n
t he g round i s l i ke ly t o b e i n c on tac t w i th a c o mp lex o f micro-organ is ms , s o me o f wh ich w i ll b e c apab le o f p ene tra t ing i n to t he wood , c o lon ising i ta nd t hen e i ther d es troy ing t he wood o r p repar ing t he way f or i t s d es truc t ion b y o ther o rgan is ms.
T he p rocesses o f c o lon isa t ion a re c o mp lex a nd t he s uccessions
a nd a ssoc ia t ion o f o rgan is ms a re o n ly b eg inn ing t o b e e luc ida ted Käär ik ( 1975 ), L evy ( 1975 a a nd b ). A n u mber o f p o in ts a re h owever b eco m ing c learer a nd i t i s we l l k nown t ha t n o t a l l s pec ies o f wood b ehave i n t he s a me way , s o me e xh ib i t ag rea ter d urab i l i ty t o d ecay t han o thers . b er o f o ther e f fec ts. 1 .
R ecen t work s uggests a n u m-
T he mo isture c on ten t o f t he wood may b e o f p ara mount i mpor tance i n d e ter m in ing wh ich o rgan is ms w i l l c o lon ise .
An a naerob ic s i tu-
a t ion w i l l s uppor t aq u i te d i f feren t m ix ture o f o rgan is ms t o a n a erob ic o ne . 2 .
3 .
T he mo isture c on ten t a nd t he d egree o f a era t ion w i l l c hange a s d ecay p roceeds. C harcoa l s hows a v ery h igh d egree o f d urab i l i ty t o d egrade b y b io log ica l a genc ies , a nd much o f t he c e l lu lar d e ta i l i s r e ta ined i nt ac t i n s i tua t ions where wood i t se lf wou ld b e t o ta l ly d estroyed .
S i te c ond i t ions a re t here fore c r i t ica l i n d e ter m in ing t he d egree o f p res erva t ion o f t he c e l l wa l l s truc ture i n wood b ur ied i n t he g round .
I ti s n o t b e-
y ond t he b ounds o f p oss ibi l i ty t ha t l ong t er m b ur ia l i n s low ly mov ing wa ter c ou ld p roduce a n a c id o r a lka l ine c he m ica l b reakdown o f wood . 2 0
C er ta in ly
f oss i l e v idence i s ac lear i nd ica t ion t ha t p e tri f ica t ion c an o ccur w i th t he c arb on o f l i v ing o rgan is ms b e ing r ep laced b y s i l ica . l ong t er m
H owever t he e v idence f or
b reakdown o f w ood b y a c ids o r a lka l is i s l arge ly n on-ex isten t
wh i ls t t here i s much e v idence o f b io log ica l d egrade , wh ich c an o f ten b e s een t o h ave s topped a t ac er ta in p o in t , p resu mab ly b y ac hange o f s o me s or t i n t he c ond i t ion o f b ur ia l . T he a rchaeo log ist i s t hus f aced w i th t he p rospec t o f f ind ing a wooden o bj ec t u sua l ly i n av ery we t c ond i t ion .
T he s ize a nd s hape may a ppear t o b e
u na l tered a par t f ro m a s of ten ing , a l most a p last ic is ing o f t he w ood.
Can i t
b e r e moved f ro m t he we t c ond i t ion i n wh ich i t was f ound a nd d r ied?
T he
a nswer i s " yes" , b u t o n ly i fc are i s t aken t o e xa m ine t he c ond i t ion o f t he wood . I fa ny o f t he wood-ro t t ing m icro-organ is ms h ave b een o n ly modera te ly a c t ive , t here may b e l i t t le v isib le e v idence w i thou t micropscop ic e xa m ina t ion . i s r equ ired i s t o k now wha t h as h appened t o t he c e l l wa l l l ayers. o r a ny o f t he m b een d es troyed?
Wha t
H ave s o me
I fs o , t hen i nev i tab ly s tresses w i l l b e s e t u p
i n d ry ing wh ich may c ause g rea t d istor t ion o f t he o b jec t .
Two c ourses a re
o pen . ( a )
S o lven t d ry ing t o r e move t he s ur face t ension e f fec ts o f wa ter d ryi ng o u t b y r ep lac ing t he wa ter w i th a s o lven t whose s ur face t ension e f fec ts l eave t he r e ma in ing p ar ts o f t he wa l l i n s i tu w i thou t d ry ing s tresses b e ing b u i l t u p .
T he r esu l t ing s a mp le may b e t he r igh t
s hape , b u t i tw i l l o f ten b e v ery b r i t t le a nd f rag i le a nd may we l l h ave c hanged c o lour . ( b )
I mpregna t ion w i th ma ter ia ls c apab le o f f i l l ing t he s paces l e f t b eh ind b y t he d es truc t ion o f t he c e l l wa l l c o mponen ts s o t ha t o n d ry ing t he r e ma in ing p ar ts o f t he wa l l a re s uppor ted b y i mpregna t ing ma ter ia ls a nd s hr inkage i s r esisted b ecause t he s paces a re a l l f i l led .
A rchaeo logy , s o f ar a s wood i s c oncerned , d ea ls w i th t hose wooden o bj ec ts t ha t h ave s urv ived c o mp le te d egrada t ion b y b io log ica l a genc ies b ecause t he c ond i t ion o f b ur ia l h as p reven ted , d e layed o r s topped t he a c t iv i ty o f t he o rgan is ms i nvo lved .
Where p ar t ia l d es truc t ion h as o ccurred c onsiderab le
d is tor t ion i s l i ke ly t o t ake p lace o n d ry ing t he wood u n less a c t ion i s t aken t o p reven t t h is h appen ing .
2 1
REFERENCES
Bravery , A .F ., 1 971 ,
'T he a pp lica t ion o f s cann ing e lec tron microscopy i n
t he s tudy o f t i mber d ecay ' . Bravery , A . F., wood" .
1 975 .
J . I nst . Wood S ci . 5( 6 ) ,
1 3-19 .
? M icro morpho logy o f d ecay i n p reserva t ive t rea ted
I n B io log ica l T ransfor ma t ion o f Wood b y Microorgan is ms ,
( Ed . W. L iese ) , Käär ik , A ., 1 975 .
S pr inger -Ver lag , Ber l in , 1 29-144.
' Succession o f micro-organ is ms d ur ing wood d ecay ' .
I n B io log ica l T ransfor ma t ion o f Wood b y M icro-organ is ms ,
( Ed . W.
L iese ) , S pr inger -Ver lag , Ber lin , 3 9-51. K irk , T .K ., 1 975 . f ung i ' .
' Che m istry o f l ign in d egrada t ion b y wood d estroy ing
I n B io log ica l T ransfor ma tion o f Wood b y Micro-organ is ms ,
( Ed . W. L iese ) , S pr inger -Ver lag , B er l in , 1 53-164. L iese , W., a nd Greaves , H ., 1 975 .
' M icro morpho logy o f b acter ia l a t tack ' .
i nB io log ica l T ransfor ma t ion o f Wood b y Micro-organ is ms , L iese ) ,
( Ed . W.
S pr inger -Ver lag , B er l in , 7 4-88 .
L evy , J .F., 1 974.
F ung i i n Wood .
S cann ing E lectron Microscopy/74 1 1 ,
4 62-468 . Levy , J . F., 1 975a .
' Co lon isa t ion o f wood b y f ung i '.
f or ma t ion o f Wood b y Micro-organ is ms ,
I n B io log ica l T rans-
( Ed . W. L iese ) , S pr inger -
Ver lag , B er lin , 1 6-23. Levy , J . F.,
( 1975b) .
' Bacter ia a ssocia ted w i th wood i n g round c on tac t ' .
i n B iolog ica l Transfor ma t ion o f Wood b y Micro-organ is ms , L iese ) , L evy , J . F.,
( Ed . W.
S pr inger -Ver lag , B er lin , 6 4-73. Mi l lbank , J . W .,
Dwyer , G ., Ba ines , E .F., 1 974 .
o f b ac teria i n wood d ecay '.
' The r o le
R ecord o f t he 1 974 Annua l C onven t ion o f
t he Br i t ish Wood Preserv ing A ssoc ia t ion ,
2 2
3 -13 .
5 .
CONSERVAT ION OF OLD WATER-LOGGED WOOD J . d e J ong
S u m mary
I n t he L ake I Jsse l a rea many s h ipwrecks h ave b een f ound a nd e xcavated.
The c onservat ion o f o ld water logged wood , i fl arge
o b jects a re t o b e t rea ted , s t il l c auses a n u mber o f p rob le ms. U s ing t he e x is t ing t rea t men t methods w ith p o lyethy lene g lyco l i t was f ound t ha t l i t t le d eter iora ted e uropean o ak , was v ery d if f icu l t t o c onserve. Based o n d a ta f ro m l i tera ture a nd t he o bserved impregna t ion r es u l ts a d iv is ion o f e uropean o ak i n to 3 c lasses i s g iven . i s b ased o n t he d egree o f d egrada t ion o f t he w ood.
The d iv is ion
T he wood o f t wo
o f t hese c lasses c an b e t reated b y e x ist ing wa ter-PEG p rocesses.
I NTRODUCT ION D ur ing t he s even teen th c en tury a p lan was made i n H o l land t o e nc lose t he Z u iderzee . t he s ea .
T he a i m was t o e stab l ish a b e t ter p ro tec t ion o f t he l and a ga inst
I t was n o t , h owever , u n t i l 1 918 t ha t t he Du tch G overn men t , a f ter
al arge f l ood i n 1 916 a nd a p er iod o f f ood s carc i ty d ur ing Wor ld War 1 , d ec ided t o h ave t he Z u iderzee s epara ted f ro m t he N or th S ea b y means o f a b arr ier d am , a nd t o c ons truc t 5p o lders i n t he f resh wa ter l ake , L ake I Jsse l , s o f or med . T he f irst p o lder , t he W ier inger meerpo lder , was d rained i n 1 930 , a nd t he b arr ier d a m was c o mp le ted i n 1 932.
T he f irst p o lder was t here fore c on-
s truc ted i n a mar ine e nv iron men t . T he o ther p o lders h ave b een r ec la i med f ro m a f resh wa ter l ake .
T he
s econd p o lder , t he N oordoos tpo lder ( Nor th-eas t-po lder ) , was d ra ined i n 1 942 , Ooste l i jk F levo land ( Eas tern F levo land ) i n 1 957 , a nd Z u ide l i jk F levol and ( Sou therm F levo land ) i n 1 968 . Z u ide l i jk F levo land i s s t i l l u nder d eve lopmen t . F igure 5 .1 g ives a n i mpress ion o f t he a rea o f r ec la i med l and i n L ake I Jsse l. Dur ing r ec la ma t ion , d eve lop men t a nd f ar m ing o pera t ions i n t he n ew p o lders many f inds o f a rcheo log ica l a nd h is tor ica l v a lue h ave b een made . R e ma ins o f n eo l i th ic s e t t le men ts , d a ted b e tween 3 650 a nd 3 350 B . C . h ave b een e xcava ted .
T here a re a lso f inds o f a more r ecen t d a te .
T he l a t ter f inds a re
ma in ly s h ipwrecks o r p ar ts o f s h ips d a t ing f ro m t he Midd le Ages t o r ecen t t imes , a nd c rashed a irp lanes f ro m Wor ld War 2 .
2 3
Bes ides b e ing a n impor tan t
T HE Y SSEL -LAK
P OLDERS
R I NGERMEE F C AKE n e t 1 25 .000 h e
R TH E ASTERN P OLD ER d r amed 1 942 4 8 .000 h a
MARKERWAARD E ASTERN P L EVOLAND d r amed 1 957 5 4 .000 h a
S OUTH F L EVOLAND d r amed 1 9 68 4 4 .000 h a
A ms te rdam
1 0
F ig . 5 .1
F ig . 5 .2
2 0
3 0
4 0
5 0
6 0
7 0 k m
T he L ake I Jsse l l and r ec lama t ion a nd d eve lop men t p ro jec t.
T he l oca t ion o f t he s h ipwrecks f ound i n t he L ake I Jsse l a rea.
f i sh ing a rea , L ake I Jsse l was i n p rev ious c en tur ies a c en tre f or n a t iona l a nd i n terna t iona l s h ipp ing , a nd i ti s t here fore n o t t o b e wondered a t t ha t t he b o t to m h as s o many s h ipwrecks.
U p t i l l n ow o ver 3 00 o f t he m h ave b een
f ound ( F ig . 5 .2 ). An u mber o f t hese s h ipwrecks h ave b een e xcava ted t o s tudy t he h istory o f t he t rade o f t he s h ipbu i ld ing a nd l i fe o n b oard . I n s evera l c ases t he e n t ire wreck , l arge p ar ts o f i t , o r t he s h ip 's i nven tor ies a ppeared t o b e o f s uch a n i n teres t a nd v a lue t ha t i tw as d ec ided t o a dd t he m t o t he c o l lec t ion o f t he Museum o f Mar i t i me Archaeo logy a t Ke te lhaven . I fi ti s d ec ided t o p reserve t he e xcava ted r e mains o f t he wrecked s h ips i ti s n ecessary t o a pp ly a c er ta in t echn ique o f c onserva t ion o f wood t o p reven t s hr inkage , c rack ing a nd d is tor t ion o f t he s h ip 's r e ma ins , wh ich o f ten h appens when o ld wa ter logged wood i s a l lowed t o d ry . THE PROPERT IES OF OLD WATERLOGGED WOOD I f wood i s k ep t i n av ery mo ist o r we t e nv iron men t i tw i l l a bsorb wa ter a nd e ven tua l ly b eco me wa ter logged .
A f ter a c er ta in amoun t o f t ime c hanges
w i l l o ccur i n t he wood s truc ture , a nd i n t he p hysica l a nd c he m ica l p roper t ies o f t he wood .
T hese c hanges a dverse ly a f fec t t he s u i tab i l i ty o f t he wood f or
c onstruc t ion p urposes , a nd a re ma in ly c aused b y microb io log ica l a t tack o n t he wood .
Physica l-che m ica l p rocesses a lso c on tr ibu te t o t he b reakdown o f t he
wood . H ow f ar wood w i l l d esin tegra te d epends o n t he wood s pec ies , i t s g row th h is tory , t he k ind o f e nv iron men t d ur ing t he p er iod t he wood h as b een u sed , a nd t he c ond i t ions a nd t he l eng th o f t he p er iod a f ter i t s u se .
Impor tan t f ac-
t ors i n t h is r espec t a re mechan ica l d a mage , t ype o f med ium , h um id i ty , 1 t e mpera ture , pH a nd r edox p o ten t ia l '2 . D ecay o f wa ter logged wood may o ccur u nder b o th a erob ic a nd a naerob ic c ond i t ions .
The amoun t o f o xygen i n
wa tersa tura ted s o i l , i n wh ich most o f t he s h ipwrecks a re f ound i n t he N e therl ands , i s sma l l , h ence t he d is in tegra t ion w i l l b e ma in ly a naerob ic .
T he
microb io log ica l d ecay c auses more d a mage t han p hysica l-che m ica l d ecay i n b o th a erobic a nd a naerob ic c ond i t ions. T h is b eco mes c lear when f inds made o f a wood s pec ies wh ich i s v ery r es isten t t o microb io log ica l a t tack , a nd f inds f ro m a n e nv iron men t where microb io log ica l a t tack c ou ld n o t o ccur ( e .g . t he N orweg ian V ik ing s h ips a nd t he Egyp t ian mum my c o f f ins ) a re c o mpared w i th d ecayed o ld wa ter logged wood I n many c ases d e ter iora t ion o f t he wood may s tar t b e fore i tb eca me wa terl ogged .
A t tack b y r o t c ausing f ung i , a nd t eredos may b e t aken a s e xa mp les.
F ina l ly t he p er iod b e tween t he mo men t t he wood b eca me wa ter logged , a nd was e xposed t o d ecay c aus ing p heno mena , a nd t he mo men t o f e xcava t ion w i l l p lay ar o le . T he p rocess o f d e ter iora t ion o f wood i n we t , a naerob ic c ond i t ions i s v isua l ised a s f o l lows
5:
A t t he o u tse t , t he r ead i ly wa ter s o lub le c o mpounds i n t he wood w i l l d i f fuse i n to t he s urround ing med iu m , f o l lowed b y r ead i ly h ydro l ised c o mpounds s uch a s t he p ec t ines a nd p en tosans .
T hen a microb io log ica l d egrada t ion o f t he
2 5
more s tab le h em ice l lu lose a nd c e l lu lose w i l l f o l low . F ina l ly o n ly l ign ine r e ma ins , wh ich c an a lso b e d eco mposed s low ly b y micro-organ is ms i n a n a naerob ic e nv iron men t .
B o th f ung i a nd b ac ter ia c ause t he microb io log ica l
b reakdown o f wood a nd b o th u se e x tra-ce l lu lar e nzy mes t o h ydro l ise h em ic e l lu lose , c e l lu lose a nd l ign ine .
I n t he c ase o f af unga l b reakdown d egrada-
t ion s preads t hroughou t t he c ap i l lary s yste m o f t he wood a t l east a s f ar a s t he e x tra-ce l lu lar e nzy mes c an p ene tra te i n to t h is s yste m
3' 4
.
T he r esu l t o f t he a t tack o n t he wood a nd t he d ecay o f t he c e l l ma ter ia l i s ac onsiderab le l oss o f o r ig ina l s treng th .
When d ry ing , o ld wa ter logged wood
s hows a v ery s trong s hr inkage , warp ing , c rack ing , a nd s o me t i mes a c o mp le te d is in tegra t ion ; c e l l-co l lapse c an a lso o f ten b e o bserved . T he c on trac ting c ap i l lary f orces o f t he e vapora t ing wa ter e xceed t he s treng th o f t he c ap i l lary s yste m o f t he d e ter iora ted wood .
A s ar esu l t o f t he d ecay o f c e l l ma ter ia l i n
t he wood t he s ize o f t he s ub m icroscop ic c ap i l lar ies i ncreases , c ausing a d ec rease i n t he s pec i f ic s ur face o f t he wood .
T he c e l lu lose b reakdown a lso
r esu l ts i n ad ecrease o f a dsorb t ive s i tes o n t he wood , r esu l t ing i n ad ecreased s we l l ing c apac i ty o f d r ied o ld wa ter logged wood a s c o mpared w i th n ew wood . I n p rac t ice , d r ied a nd s hrunken o ld wa ter logged wood s we l ls o n ly t o av ery l im i ted e x ten t when a ga in i n c on tac t w i th wa ter . i rreversib le .
Noack 6 ,7
C e l l-co l lapse i s most ly
r ecorded 9 -10% r ad ia l a nd 2 0% t angen t ia l s hr ink-
a ge i n l i t t le d ecayed wood o f t he B re mer Kogge ( t he d escr ip t ion l i t t le d ecayed i s b ased o n c he m ica l c o mposi t ion a nd wa ter c on ten t i n t he wa ter logged s ta te ) . T he l ong i tud ina l s hr inkage was a l mos t z ero . f ro m wa ter logged t o o vendry ( approx . 1 05 ° C ) .
T hese d a ta a re b ased o n d ry ing F igure 5 .3 i nd ica tes wha t t he
r esu l ts a re o f s uch a s hr inkage p rocess. F ro m i nves t iga t ions c onduc ted o n t he wood o f t he Zwa m merda m a nd U trech t s h ips i t was l earned t ha t e ven h igher d egrees o f s hr inkage may o ccur . T hese a re , c o mbined w i th d a ta r ecorded i n l i tera ture , l i s ted i n T ab le 1 . The wa ter c on ten t a s g iven i n t h is T ab le i s b ased o n t he o ven d ry we igh t ( 105 ° C ) o f t he wood .
T he more d e ter iora ted t he wood i s , t he h igher t he wa ter
c on ten t w i l l b e f or a ny g iven s pec ies o f wood .
T he b reakdown o f t he w ood a lso
c auses c onsiderab le c hanges i n t he c he m ica l c o mposi t ion o f t he wood .
T h is
i s s hown i n T ab le 2 b y g iv ing t he r esu l ts a s o b ta ined f or t he Wasa , t he B re mer Kogge 7 ,a nd t he i nvest iga t ions c onduc ted o n t he w ood o f t he Zwa m merda m a nd U trech t s h ips .
A l l d a ta g iven a re b ased o n t he o vendry we igh t o f t he
wood ma ter ia l . T ab le 1 s hows t ha t i n many c ases o ld d ecayed wa ter logged wood s hows a f ter d ry ing d egrees o f s hr inkage c onsiderab ly h igher t han t hose o f d r ied n ew wa ter logged wood .
O ld a nd d e ter iora ted wa ter logged wood c an o n ly b e a l-
l owed t o d ry i n af ew s pec ia l c ases when t he wood i s v ery s l igh t ly d egraded . T he d a ta o f t he T ab les 1 a nd 2 t oge ther s how t ha t e ven i n c ases i n wh ich a l most n o c he m ica l c hanges a re f ound , t here i s y e t ac onsiderab le i ncrease i n t he d egree o f s hr inkage a s c o mpared t o t ha t o f n ew wa ter logged wood . I ncreased d egrada t ion o f t he wood means i ncreased r ad ia l a nd t angen t ia l s hr inkage .
I n h igh ly d egraded wa ter logged wood a l ong i tudina l s hr inkage
w i l l a lso o ccur .
T he s hr inkage i n t h is d irec t ion may we l l b e o ver 1 0% .
When a n o u ter l ayer o f h igh ly d egraded woods i s o ver ly ing a l ess d egraded i nner c ore , t he h igh ly d egraded l ayer a nd t he i nner c ore w i l l s hr ink i n a l l
2 6
o ld wa te r logged wood b e fo re d ry ing
o ld wate r logged wood a f ter d ry ing
l a rge s hr inkages i n a l l d i rec t ions
a= r ad ia l b =tangent ia l c= l o ng itud ina l
—1
T he s hr ingkages a re l a rge r i n t he h igh ly d e te r iorated a reas t han i n t he r e lat ive ly s ound c o re o f t he wood
T he t hree ma in a xes i n wood a nd t he
F ig . 5 .3
d a mage d ue t o s hr inkage a f ter d ry ing ap iece o f o ld water logged w ood.
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T ab le 3 .
T he c lass if icat ion o f w ood s pec ies a ccord ing t o d urab il ity . T he d iv is ion i s b ased o n a n o u tdoor e xposure o f u n trea ted h ear twood i n c on tac t w ith a h um id s o il a nd i n at e mpo r a te c l i ma te.
L ifet i me C lass I
( years ) v ery d urab le
2 5
Wood s pec ies ( examp les ) a fromos ia , a fze l ia , a zobe , i roko , merbau , t eak , w enge
I
I I
d urab le
2 5-15
Ca l iforn ian r edwood , r ed c edar , wh ite c edar , European o ak , * Am. mahogany , s ipo mahogany , r ed meran ty ( heavy )
modera te ly d urab le
1 5-10
Oregon p ine , p i tch p ine , l arch , r ed meran ty ( l igh t ), s ape le mahogany , European wa lnut
I V
l i t t le d urab le
1 0- 5
f i r , E uropean p ine , p arana p ine , Am. r ed o ak , map le , e lm
V
v ery l i t t le d urab le
5
b a lsa , b irch , b eech , a sh , p op lar , a lder , l ime , w i l low
a t t he b oundary o f c lass I a nd I I
3 0
d irect ions d ur ing d ry ing , b u t t he o u ter l ayer w i l l s hr ink c onsiderab ly more t han t he i nner c ore .
T hese d i f ferences i n s hr inkage , c ause t he h igher d e-
g raded o u ter l ayer t o c h ip o f f f ro m t he i nner c ore .
E ven i n c ases w i th o n ly
ap ar t ia l ly c h ipp ing o f f o f t h is o u ter l ayer a l most a l l d e ta i ls o f t he t ex ture o f t he s ur face o f t he wood w i l l b e l os t . T o p reven t t hese a dverse a f fec ts i ti s n ecessary t o c onserve t he ma ter ia l . T he a im o f t h is c onserva t ion i s , a s f ar a s p ossib le t o s tab i l ise t he d i mensions o f t he f ind .
T h is means t ha t t he g oa l o f a ny c onserva t ion p rocess i s t o o bta in
a n e qu i l ibr ium b e tween wood a nd e nv iron men t , p reven t ing t he h igh d egree o f s hr inkage .
I n s o me c ases , e spec ia l ly w i th h igh ly d egraded wood , a n i mprove-
men t o f t he mechan ica l p roper t ies o f t he ma ter ia l i s d esirab le o r n ecessary . A s c an b e s een f ro m T ab le 1 e ven n ew wa ter logged wood s hr inks when d ry ing , ma in ly i n t he r ad ia l a nd t angen t ia l d irec t ions , a nd s o me s hrinkage w i l l a l most p rove i nev i tab le d ur ing a ny c onserva t ion p rocess .
T he a ccep tab le d egree o f
s hr inkage d epends l arge ly o n t he n a ture o f t he o b jec t a nd i t s u se a f ter c ons erva t ion .
I ff or e xa mp le t he o b jec t i s f a ir ly sma l l a nd h as a v ery f ine a nd
d e l ica te s ur face t ex ture ( e .g . s cu lp ture ) a nd w i l l b e u sed f or f ur ther r esearch ( archaeo log ica l o r h istor ica l ) s hr inkage s hou ld b e a s sma l l a s p ossib le .
I f ,
h owever , t he s ur face o f t he wood i s r a ther u nf in ished , a nd t he f inds w i l l b e u sed a f ter c onserva t ion t o g ive a n i mpression o f t he e n t ire c onstuc t ion ( a s i s t he c ase w i th many o ld s h ips ) s o me s hr inkage a nd s ur face d e fec ts c an b e a ccep ted . Ap ar t icu lar c ase o f w ood d e ter iora t ion h as t o b e e xpec ted i f wood i s f ound i n l and r ec la i med f ro m s ea o r l akes.
Dur ing t he t ime t ha t t hese f i nds were
c overed b y t he s ea o r l ake s ed i men ts t he wood o f t he m was a t tacked b y a naerob ic microb io log ica l a nd p hysico-che m ica l p rocesses.
A f ter t he r e-
c la ma t ion o f t he l and , c ausing a l ower ing o f t he g round wa ter l eve l , t he d eg rada t ion o f t he wood w i l l b e c on t inued b y a erob ic p rocesses a nd h ence . d e ter iora t ion i s s peeded u p
9.
An i nd ica t ion o f t he l i fe t i me o f wood u nder s uch c ircumstances c an b e o b ta ined f ro m t he d urab i l i ty c lasses wh ich h ave b een d eve loped f or n ew wood . T h is d iv ision o f wood s pec ies i n to s evera l d urab i l i ty c lasses i s b ased o n t he l i fe t i me o f =trea ted h ear twood , d ur ing a n o u tdoor e xposure a nd i n c on tac t w i th a h um id s o i l i n at e mpora te c l i ma te ( Tab le 3 ) .
E uropean o ak h ear twood
i s , a ccord ing t o t h is d iv ision , p laced o n t he b oundary o f t he c lasses 1 1 a nd 1 11. T he e xpec ted l i fe t i me w i l l b e a bou t 1 5 y ears a nd f or sma l l o b jec ts e ven l ess. METHODS OF CONSERVATION AND THEIR RESULTS Ar ev iew o n t he e x ist ing c onserva t ion t echn iques a nd t he r esu l ts o b ta ined i s g iven b y D e J ong 9 . TT 8 a pproaches c an b e d iscerned i n t he c onserva t ion o f o ld wa ter logged wood
. T he f irs t a pproach i s t o a t te mp t t o a pp ly a c oa t ing t o t he s ur face
a nd t o t he wood ma ter ia l c lose t o t he s ur face .
T he c oa t ing h as t o b e imper-
meab le t o wa ter a nd wa ter v apour t o av ery h igh d egree .
Un less v ery t h ick
c oa t ings a re a pp l ied t h is r equ ire men t w i l l n ever b e me t , a nd d ry ing w i l l o ccur a nd c racks r ead i ly f or m . s hr inkage .
H ence a c oa t ing t echn iques w i l l n o t p reven t
T he r esu l t i s mere ly a r e tarda t ion o f t he e stab l ish men t o f a n
e qu i l ibru im b e tween t he w ood a nd i t s e nv iron men t , a nd s hr inkage c orrespondi ng t o t he q ua l i ty o f t he wood a nd t he e nv iron men ta l c ond i t ions w i l l f ina l ly o ccur . 3 1
On ly i n av ery f ew c ases , where f or e xa mp le a t iny d e ter iora ted s ur face l ayer o ver l ies a s ound a nd a l most u ndegraded i nner c ore , c an s ur face t rea tmen t g ive s a t isfac tory r esu l ts.
S uch was t he c ase f or t he Ken t mere b oa t
where g ood c onserva t ion was s a id t o h ave b een a ch ieved
1
b y i mpregna t ion
a nd c onso l ida t ion o f t he s ur face o f t he wood w i th a n e pox ide r esin .
N ear
L e lys tad a 1 9 th c en tury s h ip h as b een e xcava ted a nd l e f t t o d ry i n t he o pen a ir . T he wood was i n av ery g ood c ond i t ion a nd n o o ther d a mage t han a l oca l s l igh t s ur face c rack ing o ccured a f ter a f ew y ears . T he s econd way o f a pproach i s t o i mpregna te
t he wood a s t horough ly a s
p ossib le , t he a im b e ing t o t rea t b o th t he micropscop ic a nd t he s ub m icroscop ic c ap i l lary s yste m o f t he wood .
Wa ter p resen t i n t he o ld wa ter logged wood i s
s ubst i tu ted b y n on v o la t i le c o mpounds.
I fs uch a c o mpound i s s trong ly a bsorbed
i n to t he c e l l wa l ls i tc an t ake o ver t he f unc t ion o f s we l l ing a gen t f ro m t he wa ter a nd f orce t he l a t ter t o l eave t he wood . l ess wa ter , r e ta ins i t s s wo l len s ta te .
H ence t he wood , t hough n ow c on ta in ing E specia l ly e thy leneg lyco l a nd p o ly mers
b ased o n t h is c o mpound a re s u i tab le f or t h is p urpose
1 2
'1 3 '1 4 '1 5 . T hese
p o ly thy leneg lyco ls a re c apab le , when a bsorbed i n to t he c e l l wa l ls , o f a c t ing a s as we l l ing a gen t l i ke wa ter .
Un l ike wa ter t hese c o mpounds a re n on-
v o la t i le a nd r e ma in u nder d ry c ircu mstances , i n t he wood , o nce t hey h ave b een i n troduced . S o , w i th t hese c o mpounds g ood a nd l ast ing d i mensiona l s tab i l isa t ion c an b e a ch ieved . S evera l me thods f or t he impregna t ion o f p o lye thy leneg lyco ls i n to o ld wa ter logged wood h ave b een d escr ibed i n l i tera ture a nd w i l l b e d iscussed l a ter .
I ft he h ard , waxlike p o lye thy leneg lyco l ( PEG )
g rades a re u sed a nd t he c ap i l lary s ys te m i s f i l led w i th t hese c o mpounds , a n i mprove men t o f mechan ica l s treng th c an a lso b e r ea l ised . When t rea t ing n ew wood e xce l len t r esu l ts a re a s ag enera l r u le , o b ta ined when , a bou t 3 5% o f p o lye thy leneg lyco l -b ased o n t he d ry wood ma ter ia l -i s p resen t i n t he wood
1 4
. When , a f ter o r d ur ing t he i n troduc t ion o f s uch a n
amoun t o f PEG i n t he wood , t here i s s u f f ic ien t t ime t o a l low f or a d i f fusion o f PEG f ro m t he c e l l l um ia i n to t he c e l l wa l ls , t hese c e l l wa l ls w i l l r e ma in s wo l len when t he wood d r ies o u t a nd i s k ep t a t l ow r e la tive h um id i t ies .
I ti s
s o me ti mes n ecessary t o r a ise t h is d i f fusion f ro m t he macrocap i l lary i n to t he microcap i l lary s yste m o f t he c e l l wa l ls b y s tor ing t he wood , a f ter t he i mp regna t ion w i th PEG , i n n on d ry ing c ond i t ions . Ambrose
1 6
F ro m t he i nvest iga t ions o f
i ta ppeared t ha t t he d i mensions o f o ld wa ter logged wood f ound i n
s wa mps i n N ew Gu inea were s tabi l ized when t he w ood c on ta ined a bou t 2 0% PEG w i th a mo lecu lar we igh t o f 4 00 . Based o n t he e xper ience o b ta ined i n t rea t ing n ew wood c onserva tors s tar ted t o u se p o lye thy leneg lyco ls f or t he c onserva t ion o f o ld wa ter logged wood 1 7 , 1 8 , 1 9 , 2 0 , 2 1 , 2 2 I n 1 973, u s ing t he b ath method d escr ibed b y Bar lunani
7
t he c onservat ion o f
o ld wa ter logged wood was s tar ted i n t he workshop o f t he Museu m o f Mar i t i me Archaeo logy a t Ke te lhaven .
PEG 4 000 was u sed a s ac onserva t ion a gen t .
T he e n t ire impregna t ion t ime was 1 8 mon ths , t he o b jec ts were t hen s tored i n t he impregna t ion l i qu id a t 6 0° C f or o ne mon th more .
A f ter r e mov ing t he
o b jec ts f ro m t he b a th t hey were d r ied i n a n e nv ironmen t o f i n i t ia l ly 7 0-80% a nd f ina l ly 5 0-60% r e la t ive h um id i ty .
Dur ing t h is d ry ing s hr inkage , c rack
f or ma t ion a nd warp ing o ccurred i n an u mber o f c ases . o f t he o b jec ts was a pprox i ma te ly 3 0% . 3 2
T he ma in we igh t l oss
T he c racks , wh ich d eve loped ma in ly p ara l le l t o t he f ibre d irec t ion , v ar ied i n w id th f ro m a f ew m i l l i me ters u p t o s o me c en t i me ters.
R ound o b jec ts w i th
t he c en tre o f t he t ree o r b ranch p resen t e spec ia l ly d eve loped t hese f i ssures. I n s o me c ases t he p ic ture c harac ter ist ic o f a n i nsu f f ic ien t impregna t ion w i th PEG was f ound .
N ear e nd p lanes , more o r l ess p erpend icu lar t o t he f i bre
d irec t ion , t here i s s u f f ic ien t PEG p resen t a nd n o s hr inkage o ccurs d ur ing d ry ing , wh i le o ther p ar ts s how s hr inkage . o bserved b y B rorson C hr is tensen
2 3
T hese p heno mena h ave a lso b een
.
T hese d isappo in t men ts l ed t o i nvest iga t ions i n to t he a c tua l d istr ibu t ion o f PEG i n o b jec ts wh ich a ppeared b ad ly a nd we l l c onserved .
T o o b ta in i n for ma-
t i on a bou t t h is PEG d istr ibu t ion p a t tern , s a mp les were t aken w i th a d ia me ter o f 2 .5 cm a nd ma in ly p erpend icu lar t o t he f i bre d irec t ion o f t he wood .
B y
d iv id ing t he s a mp les i n s evera l s l ices a nd e x trac t ing t he PEG w i th wa ter , a verage v a lues o f t he PEG p resen t i n d i f feren t l ayers c ou ld b e o b ta ined . I n i t ia l ly t he e x trac ted PEG was d e ter m ined t it itr i metr ica l ly b ut s ince t h is i s a t ime c onsum ing me thod , as pec tropho to me tr ic me thod was d eve loped .
9
I n F igure 5 .4 a n e xa mp le o f a PEG d istr ibu t ion c urve i s g iven .The amoun t o f PEG 4 000 e xpressed a s ap ercen tage o f t he d ry wood ma ter ia l i s p lo t ted a ga ins t t he d is tance f ro m t he wood s ur face .
T he measured wa ter c on ten t o f
t he wood d e ter m ined f ro m t he e x trac ted s a mp les i s a lso g iven .
I ti s a ssu med
t ha t n o s hr inkage h as o ccurred d ur ing t he c onserva t ion p rocess . I t was r e markab le t ha t o ak a l most e xc lusive ly c aused t he s hr inkage p robl e ms.
Dur ing i nves t iga t ions o ak a ppeared t o h ave r e ta ined i t s h igh ly i mper-
meab le s truc ture , a nd a l most n o p ene tra t ion o f PEG 4 000 i n to t he wood was o bserved .
B rorson C hr is tensen
2 3
d escr ibed t hese p heno mena .
T he wa ter
c on ten t o f t h is wood was f ound t o v ary b e tween 1 00% a nd 1 85% . We f ound t ha t t he s uccess o f ac onserva t ion p rocess a lso d epends o n t he s ize o f t he o b jec ts .
T h is i s i n n o way r e markab le a s w i l l b e e xp la ined l a ter .
I n sma l l t es t s a mp les o f l i t t le d e ter iora ted o ak h ear twood o f d i mensions 5x 5 x 1 0 cm ( t angen t ia l xr ad ia l xl ong i tud ina l ) ag ood p ene tra t ion o f PEG 4 000 was o bserved , whereas i n l arger o b jec ts s uch a s a nchorshanks o f c o mp arab le wood q ua li ty ( co mparab le wa ter c on ten t ) af ar l ess s a t isfac tory i mp regna t ion was f ound , a nd i n l arge o b jec ts s uch a s k nees a nd h u l l p lank ing t he impregna t ion was e ven worse .
T h is c lear ly i l lus tra tes t he f act t ha t r esu l ts
o b ta ined w i th sma l l t est s a mp les c an b e s trong ly mis lead ing when c onc lusions a re d rawn a bou t t he a pp l icab i l i ty o f a ny p rocess f or t he t rea t men t o f l arge o b jec ts . T he e xp lana tion o f t hese p heno mena i s b ased o n t wo f ac ts .
F irst t he
masstrans fer o f PEG f ro m t he s o lu t ion i n to t he wood i s af unc t ion o f t he a rea a va i lab le f or t h is mass-trans fer .
S ince i n sma l l s a mp les t he s ur face
t o v o lu me r a t io i n h igher t han f or l arge s a mp les , t he masstransfer p er u n i t o f v o lu me w i ll b e h igher f or t he sma l l s a mp les t han f or t he l arge o b jec ts. S econd ly t he t ranspor t o f PEG a nd o ther d isso lved ma ter ia ls i n t he wood p roc eeds w i th d i f feren t s peeds i n t he t hree ma in d irec t ions i n t he wood .
T he
t ranspor t i n l ong i tud ina l d irec t ion i s c onsiderab le f as ter t han i n t he t wo o ther d irec t ions 2 4 , 2 5 , 2 6 . The c onsequence i s t ha t i n sma l l o b jec ts , w i th s ur faces p erpend icu lar t o t he f ibre d irec t ion a t r e la t ive ly s hor t d istance f ro m e ach o ther , t he d egree o f i mpregna t ion w i l l l arge ly b e d e ter m ined b y t he " fast" 3 3
1 00 % P .E .G .
9 0
8 0
a— r equ ired amount a cco rd ing t o S ta mm b— r equ ired amoun t a cco rd ing t o Amb rose •t est p i eces
7 0
* med ium s i zed o b jec ts o l a rge o b jec ts 4 -ash a nd e lm s h ipb locks
6 0
5 0
4 0
3 0
2 0
_
1 0
4
5
7 cm
F ig . 5 .5
G raphs s how ing t he d i f ference i n impregna t ion a nd h ence c onserva t ions f or o b jec ts o f t he s ame w ood s pec ies a nd q ua l ity ( European o ak c on ta ini ng l ess t han 1 85% wa ter when w a ter logged ), b ut o f d if feren t s ize. Resu l ts f or sma l l t es t s a mp les , med iu m s ized o b jects ( e .g . a nchor s tocks ), l arge o b jects ( e .g . h u l l p lank ing a nd h eavy k nees ) a nd r igg ing b locks made o f a sh a nd e l m.
t ranspor t t hrough t hose s ur faces .
F or l arge o b jec ts t h is " fast" t ranspor t w i l l
b e t oo s low t o c o mpensa te f or t he much l arger d is tances b e tween t he s ur faces p erpend icu lar t o t he f ibre d irec t ion .
F ro m t hese c onsidera t ions o ne c an c lear ly
s ee t ha t n o c onc lusions a bou t t he c onserva t ion o f o ld wa ter logged wood f inds o f l arge d i mensions c an b e b ased o n t he r esu l ts f or sma l l t est
s a mp les .
H ow
t he p ene tra t ion o f PEG 4 000 i n o b jec ts o f d i f feren t s izes b u t o f t he s a me wood s pec ies ( European o ak ) a nd c o mparab le s ta te o f d ecay ( wa ter c on ten t 1 20-185% ) , a f ter t he s a me i mpregna t ion p rocess w i th PEG 4 000 , may d i f fer i s s hown i n f igure 5 .
Wi th t he e xcep t ion o f sma l l t est s a mp les , f or g ood d i mensiona l s ta-
b i l iza t ion , t he r equ ired amoun t o f 3 5% PEG ( w i th r espec t t o t he d ry wood ) i s o n ly f ound n ear t he s ur face o f t he o b jec ts.
T he s a me h o lds i ft he 2 0% l eve l
a s g iven b y Ambrose i s u sed . I ti s r e markab le t ha t t he s ur face c oncen tra t ion i s t he h ighest i n t he l arge s a mp les.
When u sing t he i mpregna t ion t echn ique a h igh s ur face c oncen tra t ion
may b e e xpec ted , s ince t he c onserva t ion i s s tar ted w i th a l ow PEG c oncen trat ion , wh ich i s i ncreased g radua l ly d ur ing t he p rocess.
A f ter t he r e mova l f ro m
t he b a th d ry ing s tar ts , a nd wa ter w i l l i n i t ia l ly e vapora te f ro m t he wood s ur face . T he e vapora t ing wa ter w i l l b e r ep len ished f ro m t he i n ter ior o f t he wood .
T he
r esu l t i s an e t f lux o f wa ter s a tura ted w i th PEG f ro m t he i n ter ior t owards t he s ur face , where t he wa ter e vapora tes a nd t he PEG p rec ip i ta tes .
T h is e f fec t
w i l l b e t he l arges t i n o b jec ts h av ing t he l owest s ur face t o v o lu me r a t io , h ence g enera l ly i n t he l arge o b jec ts. B esides t he s ize o f t he o b jec ts t he wood s pec ies p roved t o b e i mpor tan t , European o ak i s v ery d i f f icu l t t o p ene tra te a nd h ence t o c onserve b u t o ther wood s pec ies c an b e i mpregna ted much more e asi ly .
F ro m o ur i nves t iga tions
a nd t hose r epor ted i n t he l i tera ture , i tc an b e c onc luded t ha t o ld wa ter logged wood c an b e s uccessfu l ly c onserved w i th p o lye thy leneg lyco ls p rov ided t here i s at horough k now ledge o f t he wood t o b e t rea ted .
Know ledge a bou t t he d i f-
f eren t s tages o f d e ter iora t ion p resen t i n t he f ind a nd p ossib le c onserva t ion t echn iques a re e ssen t ia l .
Fur ther f unda men ta l r esearch f or me thods o f i m-
p rov ing t he s peed o f p ene tra t ion o f PEG i n to s o me wood s pec ies , e .g . E uropean o ak i s n eeded .
T he p rob le ms o f t rea t ing s l igh t ly d e ter iora ted o ld wa ter logged
European o ak a lso l ed B rorson C hr is tensen ( 2 3 ) t o s earch f or n ew me thods a nd d eve lope t he me thod o f d ehydra t ing t he wood w i th t er t iary b u ty la lcoho l ( t ba ) f ol lowed b y i mpregna t ion w i th a s o lu t ion o f PEG 4 000 i n t ba . n a t ion t he t ba i s r e moved f ro m t he wood b y f reeze-dry ing . u sed f or t he t rea t men t o f l arge o b jec ts i n D en mark . a va i lab le .
A f ter i mpregT h is me thod i s
R esu l ts a re a s y e t n o t
B ased o n t h is p r inc ip le t he f o l low ing e xper i men t was c arr ied o u t
i n o ur l abora tory , Wood s a mp les i n wh ich h igh ly d egraded o ak s apwood , d e teri ora ted o ak h ear twood , a nd s ound h ear twood were p resen t were d ehydra ted i n 8 8% t er t iarybu ty la lcoho l b y a xeo trop ic d is t i l la t ion o f t he a lcoho l wa ter mix ture ( 9 ) .
T he s a mp les h ad w e t we igh ts f ro m 0 .5 t o 3 0 k g a nd d i mens ions f ro m a bou t
5x 1 0 x1 0c m u p t o 1 00 x 15 x 20 cm ( rad ia l xt angen t ia l xl ong itud ina l ) . Dehyd ra t ion t ook t wo mon ths . A f ter d ehydra t ion t he wood was impregna ted w i th a s o lu t ion o f PEG 4 000 i n 8 8% t ba a t 5 0-55 ° C .
T he c oncen tra t ion was r a ised
i n 1 0% s teps u p t o 5 0% i n ap er iod o f f our weeks , a f ter wh ich t he c oncen tra t ion was ma in ta ined f or a no ther f our weeks a t 5 0% .
O ccasiona l ly PEG was a dded
t o ma in ta in t he c oncen tra t ion o f t he s o lu t ion a t 5 0% , b ecause o f d i f fusion o f PEG i n to t he wood .
T he f ina l PEG c oncen tra t ion i n t he b a th l i qu id was 5 2% .
3 5
A f ter t h is impregna t ion t he wood was r e moved f ro m t he b a th a nd c oo led .
T he
PEG c ry ta l l ises f ro m t he s o lu t ion a nd t here fore l i t t le o r n o t ranspor t o f PEG w i l l o ccur t o t he o u ts ide o f t he wood wh i le t he s o lven t e vapora tes .
A f ter t wo
weeks t he s a mp les were h ea ted f or 7 d ays u p t o 6 5°C t o me l t t he PEG .
T he
a im o f t h is i s t o d i f fuse t he PEG p resen t i n t he macrocap i l lary s yste m o f t he wood i n to t he c e l lwa l ls .
A f ter t h is t rea t men t , w h ich h as t he a dvan tage t ha t
f reeze d ry ing c an b e om i t ted a nd t ha t as econd h ea t t rea t men t c an b e g iven t o e nsure t he a bsorp t ion o f PEG i n to t he c e l lwa l ls , i t was f ound t ha t e ven i n s a mp les i n wh ich h igh ly d egraded s apwood , d e ter iora ted h ear twood a nd s ound h ear twood were p resen t , n o s hr inkage d a mage o ccurred , o n ly s o me sma l l f issures a long t he f i bre d irec t ion d eve loped.
As a r esu lt o f t he h ea t t reat men t
t he wood l ost t he f am i l iar w axy s ur face o f PEG t rea ted w ood . T he s hr inkages h ave b een measured a t s evera l s tages o f t he t rea t men t , b u t s ince t he f ina l s hr inkages a re t he most impor tan t s um mar ising w i l l b e l im i ted t o t he l a t ter . t rea t men t .
T hese v a lues a re d e ter m ined o ne mon th a f ter t he h ea t
Dur ing t h is p er iod t he s a mp les were s tored i n t he l abora tory a t
1 8-20°C a nd 5 5-65% r .h . T he f o l low ing s hr inkage v a lues were f ound f or d egraded h ear twood a nd s ound h ear twood ( i t was impossib le t o i so la te t he v a lues f or t he s apwood s ince t h is l ayer was t oo t h in a nd t oo s o f t t o p er m i t measure men ts i n t he we t s ta te w i th s u f f ic ien t a ccuracy ) :
l i t t le d e ter iora ted o ak h ear twood h igh ly d e ter iora ted o ak h ear twood
%s hr inkage
%s hr inkage
%s hr inkage
r ad ia l
t angen t ia l
l ong i tud ina l
3 . 0- 3 .7
2.9 - 4 .1
_ *
1 .8 - 2 .2
2.1 - 9 .6
1.2 - 1.7
* t h is v a lue c ou ld n o t b e measured w i th s u f f ic ien t a ccuracy b u t was l ess t han 1% . T h is me thod h as n ow b een i nvest iga ted i n to more d e ta i ls .
I tp roved s uc-
c essfu l f or s a mp les o f E uropean o ak , a sh , e lm . POSS IB IL IT IES OF CONSERV ING THE S H IPS FOUND AT ZWAM MERDAM AND AT UTRECHT I n F ebruary 1 973 t he I Jsse l meerpo lders Deve lop men t Au thor i ty e stab l ished ab oard o f Du tch e xper ts i n t he f ie ld o f wood c onserva t ion whose t ask was t o a dv ise o n t he c onserva t ion o f t he l arge f inds o f wa ter logged w ood f ound i n t he L ake I Jsse l p o lders.
I n t he f irst mon ths o f 1 973 t he Zwa m merda m s h ips ,
d a t ing f ro m R o man t imes , were f ound a nd i t was d ec ided t ha t t he I Jsse l meer p o lders D eve lop men t Au thor i ty s hou ld e xcava te a nd s a lvage t he m .
I t was a lso
d ec ided t ha t t he c onserva t ion a nd r estora t ion o f t he f inds s hou ld b e d one i n t he workshop o f t he Museu m o f Mar i t i me Archaeo logy a t Ke te lhaven . t he s h ips w i l l b e e xh ib i ted t here a f ter c onserva t ion .
S o me o f
I n U trech t i n 1 974 t wo
med ieva l s h ips were f ound a nd i t was d ec ided a ga in t ha t t he I Jsse l meerpo lders Deve lop men t Au thor i ty s hou ld s a lvage a nd c onserve t hese f inds.
I tw i l l b e
c lear t ha t t he a t ten t ion o f t he a dv isory b oard h as b een f ocussed a l most e n t irely o n t he p ossib i l i t ies o f c onserv ing t hese f inds. 3 6
T he c ond i t ion o f t he wood was t oo b ad a nd t he d a mage s us ta ined b y t he wood i n t he s o i l t oo h eavy t o e nab le s a lvag ing a nd r estora t ion o f t he s h ips a s a who le . S o i t was d ec ided t o t ake t he t imber o f t he s h ips a par t , a nd p u t t he s epara ted p ar ts o n n ew b oards u pon wh ich t he o ld wa ter logged wood c ou ld b e t ranspor ted , c leaned a nd c onserved .
A t t he e xcava t ion s i te a nd d ur ing t he t ranspor t t o t he
museu m workshop t he wood was k ep t we t .
A t t he workshop t he wood was
s tored i n wa ter , f irs t i n t e mporary b asins o u tside , t hen a f ter c lean ing i n a n u mber o f c oncre te t anks. was a dded t o t he wa ter ( 5 ) .
T o p reven t t he g row th o f microorgan is ms t hy mo l H owever t h is c he m ica l p roved d ur ing s u m mer t o
b e i nsu f f icien t , a nd i t was d ec ided t ha t t he wa ter s hou ld b e r enewed r egu lar ly . S ince t he s h ips h ad b een t aken a par t i n s epara te p ieces a nd s ince much o f t he wood , e spec ia l ly o f t he Zwa m merda m s h ips , was h igh ly d e ter iora ted , i t was d ec ided t o c onserve t he wood f irs t a nd t o r es tore t he s h ips a f terwards. Any p rocess f or t he c onserva t ion o f l arge f inds o f o ld wa ter logged wood s hou ld f u l f i l l t he f o l lowing r equ ire men ts . -T he p rocess s hou ld b e s a fe .
T h is means t ha t i t mus t b e r easonab ly
c er ta in t ha t ag ood r esu l t c an b e e xpec ted , o r t he e n t ire p rocess s hou ld b e r eversib le . -T he c onservat ion p rocess s hou ld r esu l t i n a n a s ' un ifor m ' a s p oss ib le d istr ibu t ion o f t he impregnated c he m ica ls t hroughou t t he wood.
T he
move men t o f t he c he m ica ls i n t he wood a f ter c onserva t ion s hou ld b e a s l i t t le a s p oss ib le. -T he c he m ica ls s hou ld e xer t n o s tress u pon t he wood e i ther d uring a pp l ic a t ion , o r a f terwards . -T he c he m ica ls s hou ld n o t r eac t w i th l arge d i mensiona l c hanges i n r esponse t o c hanges i n t he s urround ing med iu m . -T he c he m ica ls s hou ld n o t b e g row th med ia f or microorgan is ms .
F ina l ly
-F ina l ly t he p rocess t o b e u sed h as t o b e h azard less , -t he w orkshop i s l ocated a t ap o lder d ike - a nd r equ ire a s l i t t le l abour a s p oss ib le. I t h as t o b e p oss ib le t o a u to ma te t he p rocess. The c os ts o f t he c onservat i on h ave t o b e a s l ow a s p oss ib le. S ince s ix s h ips were f ound a t Zwa m merda m a nd t wo a t U trech t a nd a l l t hese s h ips w i l l h ave t o b e c onserved , i ti s impossib le t o e va lua te t he a pp l icab i l i ty o f a l l p ossib le p rocesses f or t he c onserva t ion o f o ld wa ter logged wood .
T he
amoun t o f wood was t oo l arge t o c onsider u sing c onserva t ions t echn iques t ha t s t i l l a re o n ly s u i ted f or a l abora tory b ench .
F our p ossib le p rocesses f or t he
c onserva t ion o f t he s h ips h ave b een s tud ied b e fore a c ho ice was made : 1 . 2 .
F reeze-dry ing f o l lowed b y af ina l t rea t men t o f t he wood . Impregna t ion w i th g lyco l me thacry la te f o l lowed b y at her ma l p o ly mer isa t ion o f t h is mono mer . ( 28 )
3 .
D ehydra t ion o f t he wood w i th a v o la t i le , wa ter s o luab le s o lven t f o l lowed b y af ina l t rea t men t o f t he d ehydra ted wood .
4 .
Impregna t ion o f t he wood w i th a s o lu t ion o f p o lye thy leneg lyco l i n wa ter .
3 7
F reeze-dry ing r equ ires l arge i nvest men ts i n b o th e qu ip men t a nd e nergy wh i le t here i s a s y e t n o e xper ience w i th t he t rea t men t o f v ery l arge p ieces o f t i mber a va i lab le .
I n a dd i t ion a t wo s tep p rocess i s i nvo lved , s ince a f i na l
t rea t men t o f t he f reeze d r ied wood i s n ecessary .
T h is makes t he c onserva t ion
more c o mplex , r equ ires l abour , a nd i ncreases c os ts ,
T he c onserva t ion o f
wood w i th g lyco l me thacry la te t hough v ery a t trac t ive i n t heory -t he mono mer i s wa terso luab le a nd c an b e p o ly mer ized t her ma l ly w i thou t t he a dd i t ion o f a c a ta lyst - i s s t i l l i n d eve lop men t a nd c anno t b e o r v a luab le o b jec ts .
u sed f or t he t rea t men t o f l arge
T he d ehydra t ion o f l arge q uan t i t ies o f wood w i th s o lven ts
s uch a s me thano l ,acetone o r t er t iary b u ty la lcoho l r equre s afe ty p recau t ions. T h is f ac t a nd t he c ons idera t ion t ha t at wo s tage p rocess i s i nvo lved , d oes n ot make t h is p rocess l i ke ly t o b e s u i tab le f or t he c onserva t iön o f t h is l arge amoun t o f o ld wa ter logged wood .
A l though t he c onserva t ion o f o ld wa ter logged
wood w i th p o lye thy leneg lyco ls h as n o t a lways b een s uccessfu l a nd a n u mber o f d rawbacks c an b e l i sted , t h is me thod was s e lec ted a s t he b es t f or t he t rea tmen t o f t he s h ips f ound a t Zwa m merda m a nd U trech t . T he f o l low ing c onside ra t ions l ed t o t h is c onc lus ion . -T he e xper ience o b ta ined i n c onserv ing l arge q uan t i t ies o f o ld wa ter logged wood i s l im i ted t o t he c onserva t ion w i th PEG ( Rosk i lde s h ips , Wasa ) , a nd t here a re p ub l ica t ions d escr ibing t he p rac t ica l p rob le ms e ncoun tered . S ince b o th t he Zwa m merda m a nd t he U trech t s h ips were t aken a par t d ur ing e xcava t ion , t he b a th me thod s ee ms t o b e t he b est t echn ique . s h ips c an s ubsequen t ly b e r econstruc ted w i th t he c onserved wood .
T he T he
c onserva t ion o f ap rev ious ly r econstruc ted s h ip h as t he d isadvan tage t ha t , e xpec ia l ly w i th t he h igh ly d e ter iora ted t imber o f t he Zwa m merda m s h ips , d a mage w i l l i ncrease a nd a v ery l arge b a th w i l l b e n eeded f or t he c onserva t ion .
Ano ther s o lu t ion i s t he s pray ing me thod , b u t t h is w i l l
r esu l t i n l onger i mpregna t ion t imes t han f or t he b a th me thod . -T he PEG b a th me thod i s at echn ica l ly s i mp le p rocess a nd h ad t he l owest e st i ma ted p rocess c osts . -T he p rocess i s s a fe w i th r espec t t o t he wood t o b e c onserved a nd i s e asi ly r eversed. -T he p rocess i s h azard less f ro m a n e nv iron men ta l p oin t o f v iew . Ab oa t , 1 3.5 m l ong a nd 2 .6 m w ide was f ound i n Krefe ld G ermany , a nd t he p ossib i li t ies f or e xcava t ion a nd c onserva t ion s tud ied . I n t ha t c ase i t was a lso d ec ided t o s a lvage i nd iv idua l e le men ts o f t he b oa t .
T hese s epara te p ar ts w i l l
b e c onserved , b y p o lye thy leneg lyco l f o l lowed b y r econs truc t ion ( 29 ) .
T h is
way o f s o lv ing t he p rob le ms o f e xcava t ion a nd c onserva t ion s hows a s tr ik ing r ese mb lance t o t he me thods u sed b y t he Museum o f Mar i t i me Archaeo logy . U sing b a ths w i th PEG 4 000 a t 6 0 ° C Brorson C hr is tensen ( 2 3 ) me t d i f f icu lt ies when c onserv ing d ecayed European o ak .
B ark man t oo , t hough i n i t ia l ly
s tar t ing w i th PEG 4 000 f or b a th t rea t men t o f o ak t imbers a nd s cu lp tures f ro m t he Wasa , a f terwards u sed PEG 1 500 f or t he b a th p rocess. Ambrose ( 1 6 ) i nd ica tes t ha t t he u se o f PEG o f l ow mo lecu lar w e igh t , r equ ires c o mpar i t ive ly l ow r e la t ive h um id i t ies t o b e ma in ta ined a f ter c onserva t ion t o p reven t l i qu if ica t ion a nd l each ing o u t o f PEG , s hou ld b e l ess t han 4 0% .
When PEG 1 000 i s u sed , r e la t ive h um id i ty
I n o ur s i tua t ion , where we h ave h igh r e la t ive h u m-
3 8
i d i t ies i n t he museum , we c hoose PEG 4 000 s ince l i qu i f ica t ion a nd l each ing o u t o f PEG o ccured w i th o b jec ts t rea ted w i th PEG 1 500 . When u sing PEG 4 000 e ach p iece o f t imber s hou ld b e s e lec ted f or a s peci f ic me thod . An u mb er o f c lassi f ica t ions o f E uropean o ak a re g iven i n l i tera ture ( 23 , 3 0 , 1 6 ) . Based o n t hese c lassi f ica tions a nd o ur own i nvest iga t ions t he f o l lowing s che me f or t he t rea t men t o f o ld wa ter logged European o ak h as b een made a nd i s n ow u sed : I Wood c on ta in ing o ver 4 00% wa ter .
T h is wood h as l ost a l most a l l o f i t s
h ard c ore . I Wood c on ta in ing 1 85-400% wa ter .
Ah ard c ore i s p resen t b u t i s c o mpara-
t ive ly sma l l . I I
Wood c on ta in ing l ess t han 1 85% wa ter .
Ah ard , l i t t le-de ter iora ted c ore
i s p resen t b e low a t h in d e ter iora ted s ur face l ayer . Wood b e long ing t o t he c lasses Ia nd I c an b e c onserved w i th PEG 4 000 ; l arge o b jec ts c onsist ing o f c lass I I wood c anno t s uccessfu l ly b e c onserved w i th s o lu t ions o f PEG 4 000 i n wa ter . C lass Iwood c an b e c onserved b y means o f t he war m b a th me thod w i th PEG 4 000 , wh i le f or c lass I wood t he c o ld b a th me thod w i th PEG 4 000 c an b e u sed . T rea t men t o f c lass I I wood w i th l ower mo lecu lar we igh t PEG i s p ossib le , b u t r equ ires many y ears ( Wasa s pray ing w i th PEG 1 500 f or 1 5 y ears ;
B re mer
Kogge t rea t men t w i th PEG 1 000 f or a n e xpec ted p er iod o f 2 0 t o 3 0 y ears ) . C onserva t ion me thods wh ich a re l ess t ime c onsu m ing s t i l l h ave t o b e d eve loped , a nd t he r esearch i n t h is f i e ld s hou ld b e s t i mu la ted . P ossib le t rea t men t f or C lass I I wood . I n s o me c ases , when t he wood i s v ery l i t t le d e ter iora ted j ust l eav ing i tt o d ry may g ive g ood r esu l ts . T h is h as b een d one f or a 1 9 th c en tury wreck f ound n ear L e lystad . T he s h ip was e xcava ted a nd l e f t t o d ry i n t he o pen a ir where i ti s s t i l l l y ing . Excep t f or a l oca l , s l igh t s urface c rack ing , n o p rob le ms a rose , a s f igure 6 may i l lustra te .
We h ave r ecen t ly o b ta ined more e xper ience u sing t h is me thod .
An u mber o f l arge o b jec ts a nd s h ip s eg men ts a l l c onsis t ing o f v ery l i t t le d e teri ora ted E uropean o ak a nd f i r were d r ied .
A l most a l l r esu l ts were g ood .
C on tro lled e xper i men ts w i th wood f ro m a 1 7th c en tury s h ip s howed t ha t a f ter af ast d ry ing u nder l abora tory c ond i tions t he s hr inkages i n t h is wood a re c o mp arab le t o t hose o ccurr ing i n n ew wood u pon d ry ing f ro m a wa ter logged c ond i t ion .
T he o bserved mean s hr inkage d a ta a re g iven i n T ab le 4 .
I tw i l l b e c lear t ha t i n many c ases s uch s hr inkages c an b e a ccep ted , s o s i mp le c on tro l led d rying o f o ld wood c an b e u sed f or s o me C lass I I wood . A f ter d ry ing a s ur face c oa t ing c an b e a pp l ied . I ft he wood i s t oo much d egraded t o p er m i t d rying , c onserva t ion i s s t i l l n ecessary .
U sing wa ter-PEG i mpregna t ions , e ven when l ow mo lecu lar we igh t
t ypes PEG a re u sed , l ong impregna t ion t imes a re n eeded .
When l arge amoun ts
o f t imber a re t o b e c onserved o ne s oon f ee ls t he n eed o f f as ter p rocesses.
3 9
On
T ab le 4 T he o bserved s hr inkage d a ta i n v ery l i t t le d egraded European o ak a nd f ir a s c o mpared t o n ew wood
% s hr inkage a ir d ry S pec ies
o ven d ry
1 *
t *
1
t
Oak h ear twood
0 .3
9 .2
0 .4
1 2.1
F ir h ear twood
0 .2
4 .2
0 .4
6 .3
n ew wood o ven d ry 1 0 .4
1 0.6 7 .7
1 l ong itud ina l s hr inkage * t
t angent ia l s hr inkage
al abora tory s ca le t he t er t iary b uty l a lcoho l PEG 4 000 me thod h as p roved i t sel f s uccessfu l.
I t g ives g ood r esu l ts a s c an b e s een f ro m F igs. 5 .7 a nd
5 .8 , a nd i s l ess t ime c onsu m ing.
Ap i lo t p lan t h as b een c ons truc ted b ased o n
t he t ba-PEG p rocess e nab l ing t he t rea t men t o f s a mp les u p t o 3m l eng th. Resu l ts w i l l p robab ly b e a va i lab le i n l ate 1 977.
I f t hey a re s a t is fac tory t he
method c an b e u sed f or t he t rea t men t o f t hose c lass I I t imbers wh ich c anno t b e a l lowed t o d ry .
4 0
F ig . 5 .6
T he wreck o f a1 9th c en tury s h ip , f ound n ear L elys tad. T he wreck was d r ied i n t he o pen a ir a nd e xcep t f or a l oca l s l igh t s ur face c rack ing n o p rob le ms a rose.
F ig . 5 .7
Two r igg ing b locks made o f e l m.
T he d ark o ne i s
t rea ted w ith PEG 4 000 i n water , t he b r igh t o ne u s ing t he t ba-PEG 4 000 method .
F ig . 5 .8
P ieces o f a n o ak t ree , d a t ing f ro m t he 2 nd c entury B .C., i n w e t c ond it ion , a ir d r ied a nd a f ter c onserv a t ion u s ing t he t ba-PEG 4 000 method.
The h o le i n
t he c onserved s a mp le was made d ur ing t he s amp l ing f or PEG d istr ibu t ion.
REFERENCES
1 .
Bark man , L .,
The p reserva tion o f t he Wasa . Wasas tud ier 5 , S ta tens
S jöh istor iska Museum S tockhol m , ( 1965 ) . 2 .
B ou te l je , L . B., a nd K iessl ing , H ., i t s d ecay b y f ung i a nd b ac ter ia '.
' On wa ter-stored o ak t imber a nd
Arch iv . Mikrobiol . 4 9 ( 3 ) , 3 05-314 ,
( 1964) . 3 .
S ta m m , A .J ., N ew York ,
4 .
Wood a nd C e l lu lose S cience . R ona ld P ress C o mpany ,
( 1964) .
Hash i moto , Y . a nd K . N is izawa , Advances i n e nzym ic h ydro lys is o f c el lu lose a nd r e la ted mater ia ls , e d ited b y E . T . Reese.
P erga mon
Press L ondon , ( 1963 ). 5 .
Müh le tha ler , B .,
C onserva t ion o f wa ter logged wood a nd l ea ther
I CO M Travaux e t p ub l ica tions Xl , E d . E yro l les , P ar is ( 1973 ) . 6 .
N oack , D .,
' Der g egenwar t ige S tand d er D i mensionsstabi lisierung
v on H o lz u nd S ch lussfo lgerungen f t ir d ie Konserv ierung d er Bre mer Kogge '. 7 .
Bre m isches J ahrbuch 5 0 , 4 3-72 ,
N oack , D .,
( 1965 ) .
D ie B re mer Hanse Kogge . Fund . Konserv ierung , F orschung
p . 1 27-156. Fr iedr ich Röver , Bre men 1 969 . 8 . 9 .
E lburg , v .d . J ., d e J ong , J .,
P r iva te c o mm .
The c onserva t ion o f o ld wa ter logged wood f ro m s h ipwrecks
f ound i n t he Ne ther lands.
I n : B iode ter iora t ion I nvest iga t ion T echn iques
I n tersc ience . 1 977. 1 0 .
R isi , J ., a nd Arseneau , D .F.,
' D i mensiona l s tabi liza tion o f wood '.
F orest P roduc ts J ourna l , 2 10-213 , 1 1.
Werner , A .E. A .,
( 1957) .
T echn ica l n otes 2 18 .
C IBA L td . Dux ford , C a mbr idge ,
Eng land . 1 2.
S ta m m , A .J .,
' D i mensiona l s tabi l isa tion o f wood w i th c arbowaxes '.
F orest P rod . J . 6 , 2 01-204 , ( 1956). 1 3.
S ta m m , A . J ., ' Ef fect o f p o lyethy leneg lyco l o n t he d i mens iona l s tab il ity o f wood '.
1 4.
Forest Prod. J . 9 , 3 75-381 ( 1959 ).
S ta m m , A . J ., ' Factors a f fec t ing t he b u lk ing a nd d i mens iona l s tab il izat ion o f wood w ith p o lyethy leneg lyco ls '.
1 5.
Forest Prod. J . 1 4 , 4 03-408 ( 1964 ).
Hes l inga , F . J . M., ' The impregnat ion a nd c onservat ion o f d eter iora ted o ak u s ing e thy leneg lyco l a nd p o lyethy leneg lyco l '.
Museo log ia No. 1 -X-
1 973 p p. 2 4-39. 1 6.
Ambrose , W.,
The t rea t men t o f swa mp d egraded wood b y f reeze-drying .
Repor t t o t he I CO M , Madr id , 1 972 .
4 3
1 7.
Bark man , L .,
' The p reserva t ion o f t he warsh ip Wasa '.
i n Oddy WA
( ed ) P rob le ms i n t he c onserva t ion o f Water logged Wood . Mar i t i me Monograph 1 6 ( 1975 ) Greenw ich . 1 8 .
L efeve ,
R .,
' Conserva t ion t rea t men t w i th p o lye thy leneg lycol o f a
wooden R o man b ucke t e xcava ted a t We m meP. Pa tr i mone Ar t ist ique , 4 , 9 7-108 , 1 9 .
Organ , R . M.,
' Carbowax a nd o ther ma ter ia ls i n t he t rea t men t o f
wa ter logged p a leol i th ic wood '. 2 0 .
Bu l l . I nst . R oya l d u
( 1961) .
S tudies i n c onserva t ion 4 , 9 6-105 , ( 1959 ) .
S eborg , R . M., a nd I n terverar i ty , R . B.,
' The p reserva t ion o f o ld
wa ter logged wood b y t rea t men t w i th p olye th leneg lyco l '.
S cience 1 36 ,
6 49-650 ( 1962 ) . 2 1.
S eborg , R . M., a nd I n terverar i ty , R .B .,
' Conserva tion o f 2 00 y ears
o ld wa ter logged b oa ts w i th p o lye thy leneg lycoP .
S tud ies i n c onserva t ion
7 , 1 11-119 ( 1962 ) . 2 2 .
Organ , R . M.,
' Po ly thy leneg lyco ls i n t he t rea t men t o f wa ter logged wood :
s o me p recau tions '. 2 3 .
S tud ies i n c onserva t ion 5 , 1 61-162 ,
Brorson C hr istensen , B .,
The c onserva tion o f wa ter logged wood i n t he
Na t iona l Museu m o f Den mark . 2 4 .
2 5 .
C openhagen , 1 970 .
Behr , E . A., Br iggs , D .R ., a nd Kau fer t , F .H ., ma ter ia ls t hrough wood '. Ku mar , S .,
( 1960 ).
' D i f fusion o f d issolved
J . Phys. C he m . 5 7 , 4 76-480 ,
' D i f fusion t hrough wood .
( 1953 ) .
D i f fusion o f b or ic a cid '.
H o lzforschung u nd Ho lzverwer tung 2 5 , 2 1-24 , ( 1973 ) . 2 6.
S ta m m , A .J .,
Wood a nd C e l lu lose S c ience .
Rona ld Press C o mpany ,
New Y ork , 1 964 . 2 7. 2 8 .
Munnikenda m , R .A .,
Pr iva te c o mm .
P ining , R ., a nd Buchwa ld , G ., u nd s e ine k onserv ierung '.
2 9 .
' Ein S ch i f f a us k arol ing ischer : Z ei t
Na turw issenscha f ten 6 1 , 3 96-398 ( 1974 ) .
Moren , R .E ., a nd C en terwa l l , B .,
' The u se o f p olyg lycols i n t he
s tab i liz ing a nd p reserva tion o f wood '. n o . 6 4 ,
( 1960 )
4 4
Modo . Techn ica l I n for ma t ion
6 .
ASPECTS OF WATERLOGGED WOOD CONSERVAT ION C .W . G regson
S u m mary
T hough wood i s p reserved i n a wa ter-sa tura ted e nv iron men t , t he s tructure i s weakened b y l each ing a nd microbio log ica l d ecay . European Oak ( Quercus S p .)
s hows a marked p a t tern o f d i f feren t ia l
d egrada t ion , as o f t s ur face s urround ing a " hard c ore" o f r e la t ive ly s ound wood .
I fa l lowed t o d ry , wa ter logged wood s u f fers i rrevocab le
s hr inkage ; i t mus t b e k ep t we t d ur ing e xcava t ion a nd s tored u nder wa ter a f ter l i f t ing . T here a re t wo ma in me thods o f c onserva t ion :
r ep lace men t o f t he
wa ter f or a l i qu id o f l ow s ur face t ension wh ich c an e vapora te w i thou t c ausing c e l l c o l lapse ; o r b u lk ing w i th a wa ter s o lub le s ubs tance wuch a s P o lye thy lene G lyco l , wh ich r e mains w i th in t he wood o n e vapora t ion o f t he wa ter . L arge s truc tures a re u sua l ly t rea ted w i th P o lye th lene G lyco l ,e i ther b y s pray ing o r im mersion i n h ea ted b a ths. Mod i f ica t ions a re r equ ired t o impregna te " hard c ore" o ak ; u se o f av ery s low r a te o f impregna t ion , w i th l ow mo lecu lar we igh t g rades o f P o lye the lene G lyco l .
Wood i n c on tac t w i th t he s oi l i s r apid ly d ecayed b y t he a c t ion o f i nsec ts , b ac ter ia a nd f ung i : t he f irs t s tep i n h umus f or ma t ion e ssen t ia l f or ma in tena nce o f s o i l f er t i l i ty a nd t he g row th o f g reen p lan ts a nd c onsequen t ly a n i ma ls . I f wood i s c overed b y ac ons tan t ly we t s o i l , t he r a te o f d ecay i s g rea t ly r ed uced d ue t o t he l ower d ens i ty o f micro-organ is ms c apab le o f f unc t ion ing i n t he a bsence o f a ir .
T hese c ond i t ions p er ta in t o e s tuar ine , f l ood p la in o r
h eavy c lay s oi ls , a nd i ti s f ro m t hese e nv iron men ts t ha t t he ma jor i ty o f a nc ien t wooden b oa ts h ave b een e xcava ted i n N or th Wes t Europe . S evera l o ther f ac tors i n f luence p reserva t ion ; wood s pecies , a c id i ty o r a lka lin i ty o f t he s o i l , ( Tab le 1 ) a nd t e mpera ture .
T he V ik ing s h ips o f G okstad l a nd O seberg 2
were r e markab ly we l l p reserved d ue t o t he ir b ur ia l i n as o i l w i th a h igh c lay c on ten t , a we t a naerob ic e nv iron men t .
B y c on trast , t he S u t ton H oo s h ip 3
b ur ied i n we l l d ra ined s andy s o i l , a mois t a erob ic e nv iron men t , h ad c o mp le tel y d ecayed l eav ing o n ly a n i mpression a nd t he d eposi t ion o f me ta l f asten ings t o e s tab l ish i t s f or m a nd me thod o f c onstruc t ion . Wa ter logged wood o f ten a ppears s ound e xcep t f or b e ing d arkened a nd s uper f icia l ly s o f t , b u t d e ter iora t ion h as a l tered i t s c he m ica l c o mpos i t ion a nd s truc ture .
The ma in e le men ts i n t he c o mposi t ion o f wood a re : c e l lu lose
h em i-ce l lu lose a nd l ign in .
4 5
r eserva t ion
L ess a c t ive
V ery a c t ive
V ery r es tr ic ted
L ess a ct ive
L ess a c t ive
V ery a ct ive
V ery r es tr ic ted
V ery r es tr icted
L ess a ct ive
A ct ion o f b ac ter ia
b ur ied u nder d i f feren t e nv ironmen ta l c ond it ions
C . )
Bogs , a c id ic
Bogs , a lka l ine
Bas ic s o i l
Bas ic s o il
Ac id ic s o i l
Ac id ic s o i l
Ac id ic s o i l
Env ironmen ta l c ond it ion
L ike l ihood o f w ood
t : 1 )
t : 1 4 >
• • •
4 6
b p
0 X
; . 4 C D
P reserva t ion p oss ib le
D ecompos it ion
Preserva t ion v ery l ike ly
Preserva t ion l ike ly
D eco mposed
L ike ly c ond it ion o f wood
C e l lu lose i s made u p o fp a irs o f g lucose u n i ts t o f or m l ong c ha in macromo lecu les , t hese c ha ins b ond t oge ther mak ing micro-f ibr i ls , wh ich , wound l i ke a b a l l o f s tr ing make u p t he l ayers o f t he wood c e l l wa l l . I ti s t he n ear ly a x ia l o r ien ta t ion o f t he f i br i ls o f t he t h ickest c e l l wa l l l ayer wh ich c on tr ibu te t o t he e xpansion a nd c on trac t ion o f wood when e xposed t o d i f feren t moisture g radien ts ; f or t he wa ter mo lecu les a t tach t he mse lves t o t he s ides o f t he f i br i ls c ausing t ransverse d i mensiona l c hanges .
H em i-ce l lu lose d oes n ot
p ossess t he c ha in f or ming p roper ty o f c e l lu lose b u t a c ts a s a ma tr ix i n to wh ich t he c e l lu lose f i br i ls a re s e t , a nd h as a much l ower r esistance t o c he m ica l o r o rgan ic a t tack .
L ign in , wh ich i s v ery r esistan t t o d ecay , l i es amongs t t he
c e l lu losic f i br i ls a nd i s most c oncen tra ted b e tween t he wood c e l ls . F ung i a nd b ac ter ia b o th p roduce e nzy mes wh ich c an b reak d own c e l lu lose a nd h em ic e l lu lose e le men ts t o t he ir b asic u n i ts f or a bsorp t ion i n to t he micro-organ is ms me tabo l ic p rocess . L ign in i s a lso a f fec ted b u t f ar more s low ly . A f ter a tt ack , t he c e l l wa l ls a re weakened a nd t he p orosi ty o f t he w ood i ncreased b y e n large men t o f t he microscopic p assageways , t h is c onsequen t ly d ecreases t he m icroscop ic i n terna l s ur face a rea o f t he wood c e l l , b o th f ac tors a f fec ting t he d rying c harac ter ist ics o f wa ter logged wood . F resh w ood c on ta ins " free wa ter" w i th in t he p ores f or c onduc t ion o f n u tr ien ts , a nd " bound" wa ter w i th in t he micro-f ibr i l s truc ture . On d rying , s hr inkage d oes n o t o ccur d ur ing t he l oss o f f ree wa ter , b u t b eg ins w i th t he l oss o f b ound wa ter , t ha t i s , a t a wa ter c on ten t o f a bou t 3 0% , t he s o c a l led " f ibre s a tura tion p oin t" . I n f resh wood s hr inkage v ar ies i n t he t hree ma jor p lanes : i n t he f i bre d irec t ion , l ong i tud ina l ly , i ti s sma l l , a verag ing l ess t han 0 .1% ; i n t he t angen t ia l p lane , a t at angen t t o t he a nnua l r ings , i tr anges f ro m a bou t 5% t o 1 0% ; a nd i n t he r ad ia l d irec t ion f ro m 3% t o 6% ; t hese v a lues i ncreasing w i th t he d ensi ty o f t he wood . I n f resh wood , l oss o f wa ter d ur ing s eason ing d oes n ot e f fec t t he c apac i ty o f wood t o r ega in i t s g reen d i mensions o n r ewe t t ing . H owever , l oss o f wa ter f ro m d egraded wa ter logged w ood c auses i rrevocab le c hanges ; f or t he wa ter w i th in t he wood i s n ow s uppor ting t he weakened s truc ture a nd i s l inked w i th e xposed t er m ina l h ydroxy l g oups o n t he r e ma in ing c e l lu lose c ha ins. On e vapora t ion , t he s ur face t ension o f t he wa ter c auses c o l lapse o f t he f rag i le c e l l wa l ls wh ich c anno t b e r es tored t o t he ir o r ig ina l d i mensions b y r ewe t ting ; t h is i s a t tr ibu ted t o t he l ow n umber o f s i tes a va i lab le f or wa ter a bsorp tion d ue t o t he d ecrease i n i n terna l s ur face a rea , a nd t he j o in ing o f t he e xposed h ydroxy l g roups t o e ach o ther .
T he wood s pl i ts l ong i tudina l ly a nd t ransverse ly
w i th c e l l c o l lapse t o b eco me p er manen t ly d istor ted . T he s hr inkage c harac ter is t ics o f wa ter logged wood v ary w i th t he e x ten t o f d ecay , a nd wood i n t h is c ond i t ion c an b e d iv ided i n to t wo main g roups : t hose wh ich a re e ven ly d egraded t hroughou t , a nd t hose where a d egraded s ur face c overs a h ard c ore o f r e la t ive ly s ound wood . E ven ly d egraded w ood c ol lapses c o mp le te ly , wh i ls t t he g rea ter s hr inkage o f d egraded s ur face ma ter ia l a round ah ard c ore c auses s p l i t t ing , c upping a nd s epara t ion a t t he i n ter face o f t he d i f feren t ia l ly d egraded z ones . P ar t ia l d ecay c an c o me a bou t b y as hor t p er iod o f b ur ia l o r al ong p er iod o f b ur ia l i n af avourab le p reserva t ion e nv ironmen t . T he mos t l i ke ly s pec ies t o p roduce t h is p a t tern o f d ecay i s E uropean Oak , wh ich e ven i n a n u n favourab le p reserva t ion e nv ironmen t s hows a s trong r esistance t o d egrada t ion . B u t t he c en tra l h ard c ore i s n o t u naf fec ted ; a vera ges o f t en s a mp les f ro m t he S wed ish warsh ip "Wasa" s howed c o mpressive s treng th i n t he d irec t ion o f t he g ra in t o b e 5 7% t ha t o f f resh wood , f lexura l 4 7
s treng th 5 8% , h ardness p erpend icu lar t o t he d irec t ion o f t he g ra in 6 3% , a nd i mpac t s treng th t o b e 2 6% t ha t o f f resh wood .
4
P assive c onserva t ion P ass ive c onserva t ion e n ta i ls ma in ta in ing t he wood i n a we t c ond i t ion d ur ing e xcava t ion , t ranspor ta t ion , a nd p retrea t men t s torage , s o p reven t ing d ry ing a nd s hr inkage .
T he d ependence o f wa ter logged wood o n t he wa ter c on-
t ained w i th in i t s s truc ture , d icta tes t he f or m o f e xcava t ion i n t ha t a l l work mus t b e c arr ied o u t i n we t c ond i t ions .
E ach e xcava t ion s i te p resen ts i t s o wn
s pec ia l p rob le ms e xcava t ion t echn iques b e ing mod i f ied t o c ircu mstances . T he V ik ing s h ips o f R osk i lde F jord d e l ibera te ly s unk a s b lock s h ips , were i so la ted f ro m t he s urround ing wa ter o f t he f jord b y ac o f fer d a m wh ich was g radua l ly p umped d ry . When t he f j ord b ed was r eached , wa ter s prays k ep t t he wooden r e ma ins we t wh i le work p rogressed .
5
T hese c ra f t were f ragmen ted
d ue t o f a i lure o f me ta l f asten ings a nd t he we igh t o f s tones u sed t o s tab i l ise t he b lockade , s o most o f t he c o mponen t p ar ts c ou ld b e l i f ted i nd iv idua l ly . E ven when t he f orm o f ac ra f t h as b een r e ta ined b y i n f i l l ing c lay o r s and , i t may n eed t o b e d is man t led . F or e x ist ing c onserva t ion f ac i l i t ies a nd e x tract i on e qu ip men t w i l l l im i t l i f t ing a s a" who le" , a s w i l l t he l oss o f mechan ica l s treng th o f t he wood i t se l f , a nd s uc t ion o f u nder ly ing c lay .
A me morab le
e xcep t ion was t he r a ising o f t he S wed ish warsh ip "Wasa" f ro m S tockho lm H arbour b y h awser a nd f l oa t ing p on toons .
L arge s ec t ions o f we l l p reserved
c ra f t h ave a lso b een r a ised , c o mp le te , f ro m t he r ec la i med p o lders o f t he Z u ider Z ee . 6 T he t ime a va i lab le f or e xcava t ion a lso i n f luences t he me thod c hosen f or l i f t ing wooden r e mains . T he r escue e xcava t ion o f t he G raveney B oa t b y t he N a t iona l Mar i t i me Museu m a nd B r i t ish Museum i n 1 970 wh ich was c o mp le ted i n t wo weeks , d id n o t a l low t ime f or r ein forc ing t he s he l l o f t he b oa t f or l i f ti ng a s a who le .
E ach s trake was s epara ted f ro m i t s n e ighbour a nd l i f ted w i th
t he h e lp o f mar ine p ly s tr ips i nser ted b enea th e ach p iece .
7 ,8
B y c on trast ,
a no ther l and s i te e xcava t ion b y t he N a t iona l Mar i t i me Museu m , t ha t o f t he 6 th B .C . Br igg ' Ra f t ' , d e manded a d i f feren t t echn ique . 9 T he r a f t , o f s ix p lanks s t i tched t oge ther , w i th c ross b a t tens t hrough p ro jec ting c lea ts , h ad t o b e r aised w i th a s l i t t le d is turbance o f t he u nder ly ing s o i l a s p ossib le .
I tl ay
o n b lue-c lay a nd c overed b y t he 1 9 th c en tury b ack f i l l , n ear t he j unc t ion o f t he p resen t R iver A ncho l me a nd t he N ew C u t , a t B r igg L incolnsh ire .
A f ter mech-
a n ica l c lear ing o f t he s i te , t he r e ma inder o f t he o verburden was c leared manua l ly f ro m b oards l a id a cross t he e xcava t ion t rench .
E xposed wood w as i m med i-
a te ly c overed w i th s tr ips o f p last ic f oa m s a tura ted b y p er iod ic s praying . Opaque b lack p o ly thene c overs p reven ted s o lar g a in d ur ing t he d ay a nd wa ter l oss a t n igh t . Due t o t he f ragmen tary n a ture o f t he p lanks i t was p ossib le t o s epara te t he m i n to c lea t u n i ts , s o me 1 .2 m l ong ; s o me d oub le c lea ts l ong it ud ina l ly a nd s o me a d jacen t c lea ts l a tera l ly were a lso l i f ted a s o ne u n i t . H eavy d u ty p o ly thene worked u nder e ach c lea t e nab led e ach s ec tion t o b e s l id o n t o as lave b earer , wh ich was t hen r e moved f ro m t he e xcava t ion t rench a nd s l id a ga in o n t o at ranspor ta t ion p a l le t c overed w i th a l arge p olythene s hee t f olded t o f or m a n e nve lope a round t he w ood a nd t he l ayers o f o ver ly ing wa ters a tura ted p last ic f oa m .
S o i t was p ossib le t o l i f t e ach s ec t ion w i th t he min i-
mu m d is turbance o f i t s c o mponen t p ar ts a nd w i thou t c on ta m ina t ing t he u nderl y ing c lay .
T he t ranspor t p a l le ts s erved a d ua l p urpose , b e ing s ubsequen t ly
u sed f or t he u nderwa ter s torage o f t he e xcava ted ma ter ia l . 4 8
A s ar u le t he v o lume o f w ood e xceeds t he c apac i ty o f t rea t men t e qu ip men t , a nd s torage f or s evera l y ears c an b e a n t ic ipa ted ; t h is i s ac o m mon p rob le m a nd t he u se o f a nc i l l iary ma ter ia ls w i th a h igh wa ter r esistance i s e ssen t ia l . Very l ong t er m s torage i s f eas ible i fa n a r t i fac t i s k ep t u nder wa ter ; s ledge s ha f ts a nd wooden p osts f ro m t he O seberg
2
w ere s tored f or 5 0 y ears ( 1904-
5 4 ) i n wa ter a nd f or ma l in b e fore a s u i tab le me thod o f t rea t men t was d ev ised . A c t ive C onserva t ion T he a i ms o f a c t ive c onserva t ion a re r e mova l o f t he wa ter w i th in t he wood a nd , b y b u lk ing o r o therw ise s treng then ing t he wood , r e ten t ion o f t he
a s
e xcava ted d i mensions . I ti s a lso e ssen t ia l t o m in im ise t he mechan ica l d a mage t ha t c an c o me a bou t b y t he e xpansion a nd c on trac t ion o f wood i n r es ponse t o c hanges i n t he r e la t ive h um id i ty . When d ea l ing w i th c o mpos i te s truc tures wh ich n eed t o b e s epara ted f or t rea t men t , t he c onsol idan t s hou ld a l low f or a ny r eshap ing n ecessary d ur ing r e-asse mb ly .
I ti s a lso d esirab le
t ha t c onso l idan ts s hou ld b e r eversib le t o a l low f or r e-conserva tion s hou ld more e f fect ive t echn iques b e d ev ised ; a nd f i na l ly t he wood s hou ld r e ta in a woodl ike a ppearance . T he means o f e xchang ing t he s uppor t ing wa ter i n wa terlogged w ood f or a more s tab le s uppor t ive s ubstance b reak d own i n to t wo ma in g roups : 1 .
R ep lac ing t he wa ter b y al i qu id wh ich b y v ir tue o f i t s l ow s ur face t ension c an b e a l lowed t o e vapora te w i thou t c ausing t he c o l lapse o f t he w ood s truc ture .
( e .g . a lcoho l-e ther-res in ; a l l f reeze d ry ing
me thods ) . I mpregna t ion w i th a c onso l idan t a f ter d ry ing i s o f ten n ecessary . 2 .
R ep lac ing t he wa ter b y al i qu id wh ich c an b e s o l id i f ied i n s i tu . ( e .g . " A lum" ,
" Ace tone-Rosin" a nd P o lye thy lene G lycol PEG ) .
A lcoho l E ther R esin T h is i s a n e x tension o f t he s tandard b otan ica l me thod o f d ehydra ting o rgan ic ma ter ia l . C on ta ined wa ter i s d isp laced b y i ncreasing c oncen tra t ions o f me thy la ted s p ir i t , wh ich i n t urn i s e xchanged f or d i-e thy l e ther wh ich h as a n e x tre me ly l ow s ur face t ension a nd c an b e a l lowed t o e vapora te w i thou t c ausing d istor t ion . I ft he wood i s h igh ly d egraded a nd f rag i le a c onso l idan t s uch a s d ammar r esin i s d isso lved i nt he f ina l e ther b a th a nd r e ma ins w i th in t he w ood c e l ls a f ter e vapora t ion o f t he s o lven t . T h is i s a n e xce l len t me thod , f or t he wood r e turns a l most t o i t s n a tura l c o lour a nd t one , o f ten r evea ling c oa t ings s uch a s t ar wh ich a re i nd ist ingu ishab le f ro m t he d eep b rown b lack c o lour o f wood i n t he wa ter logged s ta te . Bu t i tc an b e u sed o n ly w i th sma l l a rt i fac ts ; t he e x tre me ly l ow f lash p o in t a nd a naesthe t ic p roper t ies o f e ther p rec lude i t s u se o n al arge s ca le . F reeze D ry ing Me thods B y f reezing wa ter logged wood , t he wa ter w i th in i tc an b e s ub l imed f ro m i t s s o l id p hase b y warm ing u nder v acuum . Two o f t he most s er ious p rob lems e ncoun tered a re r up tures c aused b y i n i t ia l f reezing , a nd p os t d rying s hr inka ge ; b oth h ave b een l arge ly o verco me b y s oak ing t he wood i n a weak s o lu t ion
4 9
o f P o lye thy lene G lyco l 4 00 1 0 aw a ter s olub le wax . P o lye thy lene G lyco l h as t er m ina l h ydroxy l g roups wh ich j o in w i th t hose t er m ina l h ydroxy l g roups e xposed i n t he c e l lu lose c ha in s o r educ ing s hr inkage ; a lso t he e xpansion o f t he i ce o n f reezing i s c oun tered b y t he c on trac t ion o f t he P o lye th lene G lyco l . A bove 4° C t he PEG me l ts a nd i s a bsorbed b y t he wood . T h is me thod i s a n i mprove men t o n e xchang ing t he wa ter f or t er t iary b u ty l a lcoho l , wh ich f reezes a t 2 5° C s o o bv ia t ing e xpensive r e fr igera t ion e qu ipmen t , b u t l acks t he c apac i ty o f s a t isfy ing e xposed h ydroxy l g roups a nd r educ ing s hr inkage . G ood r esu l ts h ave b een o b ta ined w i th f reeze d rying a nd f ine d e ta i l i s we l l p reserved , b u t t he w ood i s l i gh t a nd f rag i le a nd may s u f fer f ro m f ine t ransverse c rack ing . I ti s o f ten n ecessary t o c onso l ida te a f ter d rying . Sma l l e ven ly d egraded wooden o b jec ts g enera l ly y ie ld t he b est r esu l ts . A lum I n troducing a s ubs tance i n l i qu id f orm i n to t he wood wh ich c an b e s o l id if ied i n s i tu i s a n e x tensive ly u sed t echn ique . F ro m t he m idd le o f t he 1 9 th c en tury t he s a l t a lum h ad b een u sed s uccessfu l ly , t he o b jec t b e ing b o i led i n as a tura ted s o lu t ion o f t he s a l t wh ich d rysta l izes w i th in t he w ood s truc ture o n c oo l ing . S ubsequen t modi f ica t ions i n t he i ndus tr ia l p repara t ion o f t he s a l t i nvo lved t he a dd i t ion o f g lycer ine wh ich l eads t o t he b reakdown o f t he s a l ts c rys ta l l ine s truc ture , a nd i t s u se i n n ow d iscon t inued .1 2 Sma l l e ven ly d egraded w ooden a r t i fac ts c an b e t rea ted r e la t ive ly e as i ly . L arge p ar t ia l ly d egraded t imbers p resen t c onsiderab le p rob lems , e spec ia l ly t he most c o m mon ly u sed b oa t b u i ld ing wood , E uropean Oak , i n wh ich t he marked p a t tern o f i ncre men ta l d ecay r esu l ts i n af irm " hard c ore" w i th in t he s of ter more e x tens ive ly d ecayed s ur face l ayers. I nsu f f ic ien t v o lume o f c onso l idan t w i th in t h is h ard c ore w i l l a l low i tt o s hr ink w i th in t he s treng thened o u ter l ayers c ausing h o l low ing o r o ther d is tor t ions . Ace tone-Rosin Wha t a c tua l ly p reven ts t he p ene tra t ion o f c onsol ida ting l i qu ids i n to o ak wood wh ich h as a " hard c ore" i s s t i l l n o t c lear ly u nderstood . I ti sp ossibly d ue t o i nso luble s u lph ides o r i nsolub le g a l la tes a nd t anna tes f ormed f ro m r eact ion o f t he r esin a c ids i n t he w ood w i th i ron f ro m t he s urrounding e nv ironmen t . T he r ecen t ly d ev ised a ce tone-rosin me thod i nvo lves c lean ing o bstruct i ons f ro m t he wood s truc ture p r ior t o t rea t men t a nd h as b een s ucessfu l ly u sed t o t rea t we l l p reserved wood .
P re trea t men t w i th d i lu te h ydroch lor ic a c id ,
d issolves wa ter i nso lub le s a l ts , wh ich c an b e washed away ; t hen a ce tone i s u sed t o d isso lve t he r esins a nd r esin a c ids . R osin ( c o lophany ) wh ich i s s o lub le i n a ce tone p roved t o b e t he mos t s uccessfu l c onso l idan t , f orm ing s uppor t ing c rysta ls w i th in t he wood o n e vapora t ion o f t he a ce tone . a ge h as b een r epor ted w i th t h is t echn ique .1 3
Al ow l eve l o f s hr ink-
P o lye thy lene G lyco l ( PEG ) T he u se o f P o lye thy lene G lyco l ( PEG ) f or t he c onserva t ion o f wa ter logged wood was i n troduced b y Moren a nd C en terwa l l i n 1 952 .1 4 P o lye thy lene G lyco l , ap roduc t o f p e troleu m i s manu fac tured i n s evera l g rades ; l ower molecu lar we igh ts a re l i qu id , t he h igher mo lecu lar we igh ts h ard waxl ike
5 0
s o l ids .
I ti s t he h igher g rades wh ich h ave t he w idest a pp l ica t ion i n c onserva-
t ion d ue t o t he ir s treng th a nd l ow h ygroscop ic i ty .
C on ta ined wa ter w i th in
t he wood i s r ep laced b y ah o t ( 60° C ) a queous s olu t ion o f PEG ; b y ma in ta in ing ac ons tan t v o lu me t he p ercen tage o f PEG i s i ncreased b y c on tro l led e vapora t ion o f t he wa ter .
On c oo ling , t he PEG h ardens t o s uppor t t he c e l l v oids .
I th as b een f ound t ha t t he mo lecu les o f t he h igher g rades a re t oo l arge t o p ene tra te t he h ard c ore o f ten f ound i n E uropean Oak .
C hr istensen d iscovered
d ur ing e xper i men ts f or t rea ting t he S ku lde lev s h ipwrecks , t ha t t he h igher g rades f i l tered i n to t he d ecayed s ur face l ayers , s urrounded t he h ard c ore a nd d rew t he wa ter f ro m i ts o c ausing i tt o c o l lapse w i th c onsequen t s ur face d is tor t ion .
T o o verco me t h is t he me thod o f t rea t men t was mod i f ied , d epend-
i ng o n t he c lassi f ica t ion o f t he wood i n to o ne o f t hree g roups .
T hose t imbers
w i th i nsign i f ican t h ard c ore ( s trakes ) s ubstan t ia l h ard c ore ( kee l , r ibs ) ; c onsiderab le h ard c ore ( s te ms ) .
F or w ood w i th l i t t le h ard c ore t he b asic
i mpregna t ion c yc le h as e x tended f ro m s even t o t wen ty f our mon ths , d ur ing wh ich t ime a 1 0% s o lu t ion o f PEG 4 000 a t 6 0° C was i ncreased t o 1 00% . H ard c ore s pec i men ts were t rea ted w i th a c o ld 2 5% s o lu t ion o f PEG 4 000 wh ich was i ncreased t o 5 0% o ver t we lve mon ths.
S low d ry ing w i th p er iod ic
i m mersion i n t he 5 0% s o lu t ion i ncreased t he s ur face c oncen tra t ion w i thin t he wood t o 6 0% . R esu l ts were d escr ibed a s g ood .1 2 B arkman i n c onserv ing t he ' Wasa ' a lso f ound t ha t r educing t he r a te o f i ncrease i n c oncen tra t ion i mproved p ene tra t ion .
E ven b e t ter r esu l ts were
a ch ieved b y u se o f PEG 1 500 wh ich h as a sma l ler molecu lar s ize , t he i nc reased h ygroscopic i ty o f t h is g rade r equ ires a c are fu l ly c on tro l led e nv ironmen t t o p reven t ' weep ing ' . V ery l arge s truc tures s uch a s t he ' Wasa ' ac on tro l led
4
c an o n ly b e t rea ted b y s pray ing ,
e nv ironmen t b e ing ma ir ta in .ed t o p reven t d ry ing d ur ing b reaks i n
t he s pray ing c yc le .
Ar t i fac ts wh ich c an b e d is man t led a re b est t rea ted b y
i m mersion i n h ea ted b a ths .
The l a t ter me thod w i l l b e u sed b y t he N a t iona l
Mar i t i me Museu m f or t he c onserva t ion o f e xcava ted wooden c ra f t .
F or t he
c onso l ida t ion o f t imber w i th ' hard c ore ' as low impregna t ion w i th t he med iu m g rade PEG 1 540 w i l l b e f o l lowed b y i mpregna t ion w i th t he h arder PEG 4 000 , f or i ncreased s treng th a nd r educ t ion i n h ygroscopc i ty .
P orous w ood w i l l b e
t rea ted w i th PEG 4 000 a lone , w i th a v ery s low r a te o f i ncrease i n c oncen tra t ion . T able 2 .
Proposed s yste m o f impregna t ion w ith Po lyethy lene G lyco l
Grade o f
Oak wood :
PEG
c ond it ion
4 000
P orous
T e mp . °C
6 0
I n it ia l
% ( W/V )
F ina l
c oncen tra t ion
i ncrease
c oncen trat ion
0 .0%
1 /10% d a ily 1y ear 1/5%
6 0%
d a i ly
r e ma inder 4 000
Res is tan t
6 0
0 .0%
1 /10% d a ily
6 0%
1 540
Very
6 0
0 .0%
1 /10% d a i ly
6 0%
r es is tan t
5 1
D esp i te t he t ime r equ ired f or t rea t men t w i th PEG , o f ten i n e xcess o f 2 4 mon ths f or r esistan t t imbers , a nd t he d arken ing o f t rea ted wood b y t he r e lease
o fc o lour ing
ma t ter , t he u se o f t h is ma ter ia l h as many a dvan tages.
I ti s n ontox ic , a nd n o h azards a re i nvo lved i n l arge s ca le u se . Once b egun , t he p rocess i s e asi ly mon i tored a nd c on tro l led . And d ur ing p ost c onservat ion r e-asse mb ly f ur ther q ua l i t ies o f PEG c an b e e xp loi ted , n o t o n ly i n t he c ase o f j o in ing b roken f rag men ts , b u t t he s hap ing o f p lank ing .
D is tor t ion i n
t he g round , o f t he o vera l l f or m o f ac ra f t , b y t he we igh t o f o verburden f or e xa mp le , c an b e r e med ied b y r ewar m ing t he PEG impregna ted w ood u n t i l i t i s p l iab le , a nd t hen r eshap ing .
T h is i s a n i mpor tan t f ac tor i n t he a ccura te
r econs truc t ion o f a nc ien t wooden c ra f t .
REFERENCES
1 .
B r 9 Sgger , A .W ., a nd S he te l ig , A ., 1 971.
The V ik ing S h ips . T he ir
a nces try a nd e vo lu t ion . -C . Hurst & C o . L td , L ondon . 2 .
R osenqu is t , A . M., 1 959 .
" The s tabi l iza t ion o f wood f ound i n t he
V ik ing S h ip o f O seberg" P ar t 1 . S tud ies i n C onserva t ion V o l . 4 N o .1 : 1 3-21 . 3 .
P ar t 2 .
S tud ies i n C onserva t ion . V o l . 4N o . 2 : 6 2-72 .
Bruce- Mi t ford , R .L .S ., 1 975 .
T he S u t ton H oo S h ip-Bur ia l . V o l . 1 .
B r i t ish Museu m Pub l ica t ions L td . 4 .
B ark man , L ., 1 975 .
" The p reserva t ion o f t he Warsh ip Wasa" i n
P rob le ms i n C onserva t ion o f Wa ter logged Wood . Oddy A . ( ed ) . Na t iona l Mar i t i me Monographs a nd R epor ts , N o . 1 6. p p . 6 5-105 . 5 .
O lsen , 0 ., a nd C ru m l in-Pederson , 0 ., 1 967.
" The S ku lde lev S h ips" .
Ac ta Archaeo log ia . Vo l . 3 8 : 7 3-174. C openhagen . 6 .
Van Der H e ide , G .D ., 1 974 .
s cheepsarcheolog ie S cheepsopyrav ingen
i n N eder land e n e lders i n d e were ld . S trengho l t H o ts tede Oud-Bussen , F levoland , 4 1 , N oarden . 7 .
E vans , A .C ., a nd F enw ick , V .H ., 1 971 . An t iqu i ty 4 5 : 8 9-96 .
8 .
Oddy , W. A ., a nd V an G eersdae le , P .C ., 1 972 . " The R ecovery o f t he Graveney B oa t" . S tud ies i n C onserva t ion 1 7 N o . 1 : 3 0-38 .
9 .
McGra i l , S ., 1 975 . Archaeo logy
1 0 .
" The Graveney B oa t"
" The Br igg R a f t r e-excava ted" L ines H istory a nd
1 0 : 5 -15 .
Ambrose , W. R ., 1 971 .
" Freeze d ry ing o f s wa mp d egraded wood" .
C onserva t ion o f Wooden Ob jec ts ( 2nd E d ) p p . 5 3-57.
T he I n terna t iona l
I ns t i tu te f or C onserva t ion o f H is tor ic a nd Ar t is t ic Works , L ondon . 1 1 .
R osenqu is t , A . M., 1 975 .
" Exper i men ts o n t he c onserva t ion o f wa ter-
l ogged wood a nd l ea ther" . i n P rob le ms i n C onserva t ion o f Wa ter logged Wood . Oddy , W. A . ( Ed .) N a t iona l Mar i t i me Museum Monographs a nd R epor ts. N o . 1 6 : 9 -24 .
5 2
1 2.
C hr is tensen , B . B., 1 970 .
The C onserva tion o f Wa ter logged Wood i n
The Na t iona l Museum o f Den mark . Na tiona l Museu m o f Den mark , C openhagen . 1 3 .
McKerre l l , H ., R oger , E ., a nd Versanyi , A ., 1 972 .
" The Ace tone/
R osin me thod f or c onserva t ion o f wa ter logged wood" .
S tud ies i n
C onserva t ion 1 7: 1 11-125 . 1 4.
C en terwa l l , B ., a nd Moren , B .,
' The U se o f P olyg lycois i n t he
s tabi l iza tion a nd p reserva t ion o f wood .' 2 5 H ay marke t , W. C . 1 .
Modo Ke m i ( UK ) L td ,
T echn ica l I n for mat ion Lea f le t , N o . 6 4.
5 3
7 .
NE W POSS IB IL IT IES I N CHE MICAL ENG INEER ING
FOR CONSERV ING S TRUCTURES OF WATERLOGGED WOOD J . R oe l fze ma S um mary
I n t he FOIL COCOON s ys te m i nvest iga ted , t he who le wood c onstruc t ion i s wrapped t w ice :
f irs t i n ap orous l ayer o f c are fu l ly
s e lec ted ma ter ia l , a bou t h al f i nch t h ick ;
n ex t i n as hee t , b u i l t o f
p o lypropy lene s tr ips , a bou t f our f ee t w ide , c are fu l ly c onnec ted b y a n a ir t igh t s ea l ing s yste m . The t op o f t he i nside o f t h is wrapping s ys te m , i s c onnec ted t o a wa ter je t v acuum p ump s ys te m , ma in ta in ing a u to ma t ica l ly a bou t 8 0% v acuum , t hus p ress ing b o th t he wrapp ing-sti f f-porus a ga inst t he wood a nd t he o u tside l ayers a ga inst t he i nside o nes . Through t he f oi l , t he p orous l ayer i s t hen c onnec ted , t o t he s tore o f t he a ppropr ia te c he m ica l l i qu id k ep t a t 6 0° C . i s c ircu la ted b y ap ump .
T h is l i qu id
S a t is fac tory r esu l ts o b ta ined s o f ar ; f or f ur ther i nvest iga t ion more man p ower a nd money wou ld b e n eeded .
Af ew e ng ineer ing s tuden ts f ro m t he Amsterda m T echn ica l C ol lege a ccep ted t wo y ears a go a s ab acca laureous p ro jec t , t he d esign a nd c onstruc t ion o n a t r ia l i nsta l la t ion f or a n e ng ineer ing me thod f or t he p reserva t ion o f l arge p ar ts o f wa ter logged wood .
T h is me thod may b e a pp l icable t o wooden s h ip c onstuc-
t ions o r , may b e , e ven who le s h ips .
Wi thou t c ons ider ing t he c he m ica l
p rocess c hosen , t he a i m was t o i nvest iga te t he p oss ibi l i ty o f s ub merg ing l arge p ieces o f t imber i n ah ea ted l i qu id , w i thou t c onstruc t ing a t ank o r c ont a iner . T he i nvest iga t ion was s uperv ised b y t he " Cen traa l L abora tor ium" Ams terda m ( D ir . I r . J . L odew i jks ) .
T he p ro jec t was s ponsored b y t he
Du tch Min istry ( CRM ) a nd R oya l Du tch S he l l O i l C o .
The work o f t he s tu-
d en ts , a f ter f in ish ing t he ir i n i t ia l p art o f t he p ro jec t , was t aken o ver b y me mbers o f t he i nst i tu te f or med ica l r eva l ida t ion u nder Dr . F .J . M. H eslinga ( Vr i je Un iversi te i t Ams terda m ) . A c t ive h e lp was r ece ived f ro m t he s ta f f o f t he Amsterda m Mar i t i me Museu m ; c he m ica l i ndustr ies , P h i l l ips Duphar , DSM a .o . T he a im o f t he i nves t iga t ion was t o a ch ieve s ub mers ion b y b u i ld ing a round t he wooden c onstruc t ion , t wo l ayers o f f lex ib le ma ter ia l .
T he f irs t , w i th a
t h ickness o f a bou t h a l f a n i nch , h av ing s t i f fness i n t he d irec t ion p erpend icu lar t o t he s ur face o f t he l ayer , b u t b e ing p orous i n t he d irec t ions p ara l le l t o t he s ur face : F ig . 7 .1. 5 5
The s econd l ayer c overing t he f irs t , e nc losed t he who le c onstruc t ion i n a n a ir t igh t f o i l , b u i l t f ro m l ong s hee ts a bou t t hree f ee t w ide . L ike t he i nside s ur faces o f h ousewa l ls c overed w i th wa l l p aper , t he who le s h ip c onstruc t ion i s n ow wrapped i n t he t wo l ayers , f or m ing a " FOIL COCOON SYSTE M" b o th i nside a nd o u tside ; F ig . 7 .1. On t he t op o f t he c onstruc t ion , t hrough t he p las t ic f oi l , t he p orous l ayer i s t hen c onnec ted ( l ine 1 ) w i th a s yste m o f wa ter je t v acuum p u mps , d isc harg ing t he a ir a nd wa terda mp f ro m t he p orous l ayer , h ence p ressing b o th l ayers o n t he wood b y t he a t mospher ic a ir p ressure , l eav ing t he t h ickness o f t he p orous l ayer i n tac t d ue t o i t s v er t ica l s t i f fness.
N ex t , o ther o u tside
c onnec t ions ( l ines 2 ) t o t he p orous l ayer a re made t hrough t he o u tside wrapp ing f o i l . Two o n t he b ot to m o f t he c onstruc t ion , l ead ing t o af lu id s tore t ank ( w i th h ea t ing c o i l ) h ence a l lowing t he f lu id t o e n ter t he p orous l ayer when v acuum i s b u i l t u p o n t he t op .
T he o ther c onnec t ions ( l ines 2 ) a re o n t op o f
t he s truc ture , work ing a s af lu id d ischarge , h ence i n troduc ing a t op l eve l o f t he f lu id , t o b e ma in ta ined b y t he amoun t o f v acuum r ea l ised b y t he wa ter je t p u mps , wh ich a re a u to ma t ica l ly c on tro l led b y al eve l i nd ica tor a nd s w i tch c on tro l . The t op d ischarge c onnec t ion l ead ing b ack t o t he s tore t ank , a nd a c ircu la t ion p u mp i nsta l led i n t h is c ircu i t , makes f lu id c ircu la t ion p ossib le t oge ther w i th t he t her mosta t ica l ly c on tro l led t e mpera ture l eve l . Wa terda mp o r d rops a re c o l lec ted i n at ank
c on ta in ing c ircu la t ion wa ter
f or t he p ressure p u mp f eed ing t he wa ter je t v acuum p u mps , mak ing t he who le s ys te m b asica l ly a c losed c ircu i t ; s ee F low S hee t F ig . 7 .2 . Photographs i n F ig . 4g ive a n i mpression o f t he i ns ta l la t ion w i th measuri ng a nd c on tro l e qu ip men t .
An e ng ineer ing s che me b ased o n t hese p r incip les
c a l ls f or s o me r e marks d escr ibing i t s l im i ta t ion . 1 . Vapour t e mpera ture u nder v acuum d rops , s ince t he wa ter i n t he c ircu la tor s tar ts b oi ling .
F ig . 7 .3 s hows t he d rop o f b oi ling t e mpera ture
a ga inst p ressure a bove wa ter l eve l , a nd s hows t ha t a t a bou t 8 0% v acuum , ( 0 .2 a tm . p ressure ) wa ter b o i ls a t a bou t 6 0
°C .
T h is means , t ha t i ft ha t
t e mpera ture i s c hosen a s a ccep tab le f or t he l i qu id f or d i f fusion i n to t he wa terl ogged wood , t he h e igh t o f t he c ocoon-wrapped s truc ture n ever c an b e h igher t han 8 0% o f 3 3 f ee t , mak ing a bou t 2 6 f ee t . I fh igher , t he p last ic f oi l o n t he b o tto m o f t he s truc ture wou ld n ot b e s uc t ioned a ga ins t t he s truc ture , u ndergoing p ressure f ro m t he l i qu id c o lu mn a bove , a nd c o l lapse .
There s ee m t o b e
p ossib i l i t ies i n t he a pp l ica t ion o f a" wa ter l ock d ev ice" , p ossib ly e nab l ing s evera l h e igh ts o f 2 6 f ee t a bove e ach o ther , b u t e xper i men ts i n t h is f ie ld h ave n ot y e t b een d one , s o f or t he t ime b e ing , a‘Max i mum c o lu mn h e igh t o f 2 6 f ee t e x is ts , a l though t he t e mpera ture o f 6 0° C s ee ms t o b e i n a ccordance w i th t he w ishes o f c he m ists , r egard ing p re ferred d i f fusion t e mpera ture . 2 .
A ir l eak ing a nd f oi l s ea l ing a ccuracy .
Much a t ten t ion was g iven t o t h is p rob le m , b e ing o f c rucia l i mpor tance f or t he who le s yste m .
We f ound g ood p ossibi l i t ies i n s e lec ted s ea l ing s ys te ms
o f p olypropy lene f o i l , t he l a t ter ma in ta in ing s u f f ic ien t s treng th a t t he t e mpera ture d e manded .
On t he o ther h and , t he s t i f f p orous l ayer u ndernea th
t he p las t ic f o i l s hou ld b e smoo th e nough t o a vo id p oss ib le l eaks p ene tra t ing t he o u tside f oi l .
A f ter e labora te s earch , u se fu l ma ter ia ls a ppeared , a l lowing
t he v ast t hree d i mensiona l d is tor t ion n ecessary . 5 6
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F low s heet o f t he p ilot p lan t .
sp r ea Ss
F ig . 7 .3
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Zg ze , . 2 .
The b o i l ing p o in t o f wa ter r e la ted t o a t mospher ic p ressure.
F ig. 7 .4
The V acuu m c ocoon t est ing i ns ta l la t ion .
3 .
A g ood c on trol s yste m t o ma in ta in t he v acuu m i s n eeded , o therw ise
c o l lapse o f t he f o il w ou ld o ccur , c aus ing l i qu id l eakage. A mercury l eve l p ressure meter , w ith v ar iab le e lectr ic c on tac t was u sed . 4 .
F lu id c ircu la t ion t hrough t he p orous l ayer s hou ld b e e qua l ly d iv ided
a l l o ver t he s ur face o f t he l ayer .
As o n ly s low c ircu lat ion i s n eeded , " dead
c orners" w i l l b e i nev itab le , c aus ing l oca l t e mpera ture d rop.
T h is w as o ver-
c ome b y empty ing t he who le s yste m a t i n terva ls , l e t ting a l l t he l i qu id i n to at ank u ndernea th t he l evel o f t he s tructure. A s n o s pec ia l c he m is try w as c ons idered i n o ur e xper i men ts , water w as u sed a s c ircu la t ing f l u id . 5 . Bu i ld ing a c ocoon a round p ar ts o r s tructures w i l l n o t a lways b e p oss ib le. I fi ti s , amongs t t he a dvan tages a re : " large" e ven " very l arge" p ar ts c an b e s ub merged ; d istor t ion t hrough s hr inkage c an b e l im ited , when s evera l p ar ts i n as tructure s uppor t e ach o ther ; i n many c ases a c ocoon m igh t b e h igh ly c os t-sav ing b y a vo id ing l arge t anks w ith v ast q uan t it ies o f ( poss ib ly d angerous ) l i qu ids. CONCLUS ION W ith in t he r estr ict ions men t ioned , t he p rob lems a round t he f o i l c ocoon s yste m a ppear t o h ave a ccep tab le s o lut ions.
F ur ther i nvest iga t ion i n t he d i-
r ec t p ract ica l d irec t ion w ou ld b e u sefu l ; t he e n thus ias m a nd i nven t iv ity o f t he ma in ly v o lun tary r esearch workers , i s h owever o verwhe lm ing t he f i nanc ia l r esources.
C ons idera t ion o f t h is method b y t hose who a re i nterested i n t he
p reserva t ion o fb ig wa ter logged c onstruct ions c ou ld l ead t o more c oord inat ion a nd p oss ib i l it ies.
5 9
D ISCUSS ION Oddy :
C an b ac ter ia b e u sed t o i ncrease t he p orosi ty o f w ood , b y c on tro l led a t tack o n t he c e l l s truc ture t o a l low PEG o r o ther c onso l idan ts t o p ene tra te more r ead i ly?
L evy :
F or s ap wood , y es ;
f or h ear t wood , a s f ar a s Ik now , t he
a nswer i s n o . Turner :
D oes t he t ype o f b ur ia l e nv iron men t d e ter m ine t he p res erva t ion o f w ood .
L evy :
Yes , i ti s t he ma jor f ac tor . Where t he b ur ia l c ond i t ions a re d ry y ou g e t v ery s ound p reserva t ion . I n we t a era ted c ond i t ions y ou c an g e t a c t ive f unga l d ecay ;
i n a naerob ic
c ond i t ions where t he wood i s c o mp le te ly wa ter logged a nd a t s o me d ep th t hen t here i s v ery l i t t le d ecay . d e J ong :
We h ave a n umber o f wrecks f ound j us t a f ter p umping o u t t he wa ter f ro m t he Z u ider Z ee p o lders wh ich were i n a v ery s ound c ond i t ion . T en t o f i f teen y ears l a ter , when we were a b le t o e xcava te t he s h ips , we f ound t ha t a era tion o f t he s oi l a nd t he l ower ing o f t he g round wa ter t ab le c aused t he s ec t ions o f wreck a bove t he wa ter t ab le t o b e c o mple te ly d es troyed .
I n a naerob ic c ond i t ions y ou c an
e xpec t t he wood t he p reserve f a ir ly we l l , b u t when i tb ec o mes a erob ic d egreda t ion i s s peeded u p e nor mous ly . C ru m lin-Pedersen :
Our p rob le m i s t ha t European o ak was p robab ly t he b est s h ipbu i ld ings ma ter ia l wh ich was a t h and f or c en tur ies, a nd t hus , whereas t here a re v ery g ood me thods d eve loped f or o ther s pec ies o f wood where y ou c an g e t p ene tra t ion , w i th European o ak t here i s n o p ene tra t ion e xcep t f or t he f irs t c en t i me tres o f t he s ur face .
T oday we s t i l l h ave a
n umber o f impor tan t s h ips b u i l t ma in ly o f o ak awa i t ing c onserva t ion .
D oes Dr . d e J ong h ave a ny c ost f igures
c o mpar ing c onserva t ion b y PEG w i th c onserva t ions b y b u tano l?
I n r ound t er ms o ur c osts were £ 5 p er l i tre
v o lume o f wood f or PEG a nd £ 7 f or b u tano l .
S econd ly ,
we h ave d eve loped o ur me thods o n t he b asis o f t he n or th European c l i ma te , b u t e ven h ere we r equ ire p roper a ir c ond i t ion ing s ys te ms when we d isp lay c onserved t imber . I n t ropica l c ond i t ions t h is r equ ire men t i s t oo c ost ly t o mee t .
C ou ld we f ind a no ther e le men t t o p u t i n to t he t im-
b er wh ich wou ld n o t r equ ire a l l t ha t a ir c ond i t ioning? d e J ong :
The PEG me thod c osts a bou t 2 ,000 Du tch g u i lders , t ha t i s £ 450 p er c ub ic me tre o f wood t rea ted .
We o n ly h ave
e xper ience o n al im i ted l abora tory s ca le w i th t he t er t iary b u ty l a lcoho l me thod wh ich we t h ink w i l l b e 5 0 p er c en t more e xpensive . One s hou ld f irs t i nves t iga te t he c ond it i on o f t he wood a nd t hen d ec ide u pon t he s pec if ic c onserv a t ion n eeded .
F or e xa mp le w i th t he Z u iderzee t imber
t he r esu l t o f c on tro l led d ry ing c an b e f a ir ly g ood f or C lass I I t imber , a nd t ha t t rea t men t i nvo lves a l o t l ess money . 6 0
Oddy :
I th ad b een s ugges ted e lsewhere t ha t r eservoirs a nd l akes c ou ld b e u sed t o s tore e xcava ted wa ter logged ma ter ia l , b u t t here i s t he p rob le m t ha t y ou a re c hang ing t he c ond it i ons , t he wa ter i n t hese l akes w i l l b e a era ted a nd t hus y ou w i l l g et d ecay u n less y ou c an a dd c he m ica ls t o p rev en t t he g row th o f m icro-organ is ms . A s f or t he c on tro l o f t he a t mosphere i n d isp lay a nd s torage a reas , p eop le h ave o f ten s a id t ha t t he l ower t he mo lecu lar we igh t o f p o lye thy lene g lyco l t he b e t ter t he c onserva t ion b ecause y ou g e t b e t ter p ene tre t ion . B u t t hen t here i s t he p rob le m t ha t a s y ou l ower t he mo lecu lar we igh t o f PEG i tb eco mes more a nd more h ygroscopic s o a ir c ond i t ion ing w i l l b e r equ ired i n f u ture .
L evy :
G e t t ing t he wa ter o u t w i thou t d estruc t ion o f t he ma teria l i s t he ma jor p rob le m . I fy ou c an d o t ha t y ou migh t b e a ble t o u se , s ay , ac o m merc ia l i mpregna t ion p lan t t o p u t i n o ne o f t he o rgan ic s olven t t ype wood p reserva t ives i n wh ich wou ld k i l l o f f a ny f ung i t ha t r e ma in , b u t a l though i t wou ld i mpregna te wha t wood r e mains i t wou ld n ot b e misc ib le w i th wa ter ;
PEG i s misc ib le w i th wa ter a nd y ou
c an r ep lace t he wa ter s lowly .
Any th ing t ha t i nvo lves
h and l ing o r e xpensive c he m ica ls i s g oing t o p u t t he p r ice u p ; j us t h o ld ing a b oa t i n al ake o r ar eservoir f or s o me t ime p u ts a c os t o n i t , b ecause i th as g ot t o b e t ranspor ted t here a nd t aken o u t a nd e xam ined f ro m t ime t o t ime . C lassi fy ing y our t imber a s s ugges ted b y Dr . d e J ong s o t ha t y ou u se t he a ppropria te me thod w ou ld s ee m t o b e a way o f min im ising c osts. Oak i s a ma jor d i f f icu l ty , i t h as a v ery b road r ay wh ich i s n o t s trong a nd c o l lapses , a nd s o me t i mes t he ma in wa ter t ranspor t s yste m i n t he t ree may g e t p lugged w i th i ngrow th i n to t he v esse ls s o t ha t t he p er meab i l i ty i s v ery much l ess ; t h is p ar t icu lar ly a pp l ies t o t he t imber u sed f or s h ipbu i lding b ecause i ti s p robab ly c hosen s pec ia l ly f or i t s i mper meabi l i ty . T ha t i ncreases t he p rob le m o f r e mova l o f wa ter o r g e t t ing a ny o ther ma ter ia l i n to t he w ood . d e J ong :
We d id s evera l e xper i men ts t ry ing t o e xchange t he wa ter f or o rgan ic l i qu ids b u t we f ound t ha t i n many c ases t here was a s hr inkage o f t he wood wh ich was t oo much t o b e a ccep tab le . Wha t s hr inkages d o o thers t h ink c an b e a cc ep ted d ur ing c onserva t ion , b ecause t he wood when e xcav a ted w i l l b e i n a n e xpanded c ond i t ion?
J ohns ton :
C an we f ind a way , where we w ork f ro m t he i nside o u t b y i n jec t ion o f s o me s or t , w i thou t d es troy ing t he f i bres t ha t h ave b een d a maged i nside?
Levy :
T o g e t t o t he i nside i n t ha t s ense y ou wou ld h ave t o d r i l l i n to ap lank , a nd p u t s o me d i f fusab le ma ter ia l i n , a nd i n wood p reserva t ion f or i nstance , t h is i s a me thod o f
6 1
t rea ting a b ea m i n s i tu .
T he b ig p rob le m f or a rchaeo lo-
g ica l c onserva t ion i s h ow a re y ou g o ing t o g e t y our ma ter ia l i nside f or i tt o d i f fuse t hrough .
T here a re s ap
d isp lace men t me thods , p robab ly n o t f easib le w i th o ak , where t he s ap i n at ree t runk i s d isp laced b y ah ead o f p ressure a t t he b u t t e nd p ush ing t he p reserva t ive f lu id i n a nd t he s ap o u t .
I fy ou c an g e t t he p lank a nd o r ien ta te
t he d irec t ion c orrec t ly , s o t ha t y ou h ave g o t t he f l ow r igh t , y ou migh t b e a b le t o r ep lace t he wa ter t ha t way i n t he s ap wood , b u t y ou w ou ld o n ly b e a b le t o d o t ha t I s hou ld t h ink w i th Dr . d e J ong 's c lass 3 t imber a nd p erh aps s o me o f t he c lass 2 . d e J ong :
Wi th c lass 3 o ak t ranspor t o f l i qu id w i thin t he t imber i s v ery s low .
When u sing wa ter a nd wa ter d issoved c he m i-
c a ls h o les wou ld h ave t o b e d r i l led v ery c lose t oge ther ; f or e xa mp le t o c o mp le te w i th in 2 y ears y ou wou ld n eed h o les e very 6 cm . Oddy :
On a sma l l s ca le we c an c onserve E uropean O ak s uccessf u l ly b y e i ther t he a lcoho l/e ther/resin me thod o r b y McKerre l l 's r ecen t a dap ta t ion o f t h is u s ing a ce tone f or d ehydra t ion , a nd t hen r esin d isso lved i n a ce tone f or i mpregna t ion . T here a re s er ious p rob le ms i n u sing t h is o n a ny th ing b igger t han a l abora tory s ca le .
Mc-
Kerre l i s t ry ing t o d o t h is b u t i t may we l l b e e xpensive a nd t he s a fe ty p rocedures a nd r es tr ic t ion w hich wou ld b e p laced o n ap lan t o f t h is s or t wou ld p robab ly b e o u tside t he c apab i l i t ies o f most Museums. C ru m l in-Pedersen :
Dr . d e J ong a sked wha t s hr inkage was a ccep tab le t o a rchaeo log ists.
F or e dge j oined b oa ts t he s hr inkage
s hou ld b e l ess t han 2p er c en t .
T h is i s l ess t han t he
n a tura l s hr inkage o f f resh w ood , b u t V ik ing s h ips f or e xa mp le were b u i l t o f G reen Oak , r ecen t ly f e l led , where t he mois ture c on ten t i s a bove f i bre s a tura t ion p oin t . T here i s n o e x tra s we l l ing f ro m t he e x tra amoun t o f wa ter i n wa ter logged wood o f t h is t ype .
A s l ong a s y ou s tay
a bove t he s a tura t ion p oin t o f t he f ibres y ou a re a t t he s a me d i mensions a s a t t he mo men t o f b u i ld ing t he v esse l a nd t here fore t he c ond i t ion y ou e xcava te i ti n i s t he c ond i t ion t ha t y ou wan t t o ma in ta in d ur ing c onserva t ion . T he l arger n on/edgedjoined s h ips h ave f ra mes wh ich d o n ot t end t o s hr ink l ong i tud ina l ly , a nd a s t he p lank ing s hr inks s o g aps a re l e f t b e tween t he p lanks .
Aesthe t ic
c onsidera t ions c ou ld d e ter m ine h ow much s hr inkage c an b e a ccep ted h ere . F or t he workab i l i ty o f t imber a f ter c onserva t ion . Me thods s hou ld b e d eve loped t o a l low a rchaeo log ists t o p u t t he p ieces t oge ther a nd r e-shape t he m .
Our r ecen t
e xper iences w i th t he b u tano l g lycol me thod i s t ha t i t
6 2
g ives i n g enera l av ery f ine r esu l t w i th l ess s hr inkage t han o ther me thods , b u t i ti s h ard t o r e-shape t he wood , e ven i f we p u t i ti n ab a th o f h o t g lyco l we c anno t b end i t b ack .
T h is p rob le m i n f ac t a f fec ted a most u se fu l p iece
o f t he S ku lde lev s h ips , t he s te m o f S h ip N o . 3 , s o we c annot r ep lace i ti n t he s h ip . Varra l l :
G enera l ly y ou f ind t ha t a l l t hree o f Dr . d e J ong 's c lasses o f t imber d egrada t ion a re p resen t i n o ne p iece o f t imber . T he s ys te m u sed t o c onserve t he h ard i nner c ore may n ot b e t he b est t o p reserve t he o u ter s ur face d e ta i l where t he wood w i l l b e s o f t . T he c lassi f ica t ion i s u se fu l t o e nab le e ach p iece o f t im-
d e J ong :
b er t o b e g iven i t s a ppropr ia te t rea t men t , a nd t hus o ne i s a b le t o r educe t he c onserva t ion c osts . McGra i l :
Are t he wa ter c on ten ts a nd t he s hr inkage f or , s ay , t he Bre men C og o r f or t he Zwa m merda m b oa ts i n Dr . d e J ong 's T ab le 1 a mean v a lue f or t he who le s h ip o r a re t hey f or o ne s pec i f ic t imber i n t ha t s h ip?
d e J ong :
T hey a re mean v a lues o f 4t o 7s a mp les wh ich were d r ied e xper i men ta l ly .
Wr igh t :
Wha t i s t he p resen t s ta te o f t he a r t o f c onserva t ion , a nd a re we o p t im ist ic o r p esi m ist ic? We a re r a ther o p t im is t ic a bou t p ossibi l i t ies o f c onserv-
d e J ong :
i ng l arge s truc tures o r l arge amoun ts o f t imber , b u t t here a re many p rob le ms t o b e s o lved . Id on ' t s ee a ny r eason f or p essi m is m a t t h is s tage .
L evy :
I t
d epends o n t he n u mber o f p eop le , t he amoun t o f money , t he i n te l lec tua l c apac i ty o f t he p eop le work ing o n i t , a nd a bove a l l l uck .
Bu t r ecord ing b e fore c onserva t ion i s
e ssen t ia l , e ven i f we d o g e t a ccura te c onserva t ion y ou mus t s t i l l r ecord d i mensions a nd measure men ts a nd t he c ond i t ions u nder wh ich t he f ind was o r ig ina l ly d iscovered .
E d i tor ia l N o te : N a t iona l Mar i t i me Museum Monograph N o . 1 6 i s r e levan t t o t h is d iscussion : Oddy , W. A .,
( e d .) 1 975 ,
P rob le ms i n t he C onserva t ion o f Wa ter logged Wood .
6 3
8 .
ETHNOGRAPHY AND L IV ING TRAD IT ION O lo f H asslö f S um mary
Th is p aper c onsiders p rob le ms c oncern ing d i f feren t me thods a nd k inds o f s ource ma ter ia l u sed t o e xp la in t he d eve lop men t o f 't he s h ipb u i ld ing t echn ique .
F our c h ie f me thods h ave d eve loped .
F irs t :
I nvest iga t ions i n a rch ives a nd l i tera ture , t ha t i s wr i t ten s ources . S econd : I conograph ica l a na lysis o f p ic tures , s cu lptures a nd t he l i ke . T h ird : Archaeolog ica l e xcava t ions a nd u nderwa ter e xp lora t ions o f f inds f ro m t he e ar th a nd t he s ea b ed .
F our th : E thnograph ica l f ie ld
i nqu ir ies a bou t s h ips a nd s h ipbu i lders i n t he ir workshops. I ts tresses t he i mpor tance o f t he e thnograph ica l s ource ma ter ia l , wh ich i s l i v ing i n i t se l f a nd s o a nima tes e ven t he s i len t o b jec ts , t he meagre t ex ts a nd t he myster ious p ic tures f ro m l ong a go . A t ten t ion i s c a l led t o t he c oncep t o f l i v ing t rad i t ion a nd i ti s emphasized t ha t i t must b e s cru tin ized w i th r egard t o t he s ix d i f feren t means o f c o m mun ica t ion - o r t rad i t ion med ia , t hrough wh ich e v idence o f p eop le a nd t he ir a c t iv i t ies a re t rans m i t ted t hrough t i me , s pace a nd s ocia l g roups .
T he Organ izing C o mm i t tee f or t h is S y mpos iu m h as i nv i ted me t o g ive a n i n troduc tory l ec ture o n E thnography a nd L iv ing Trad i tion .
Th is i nv i ta t ion i s ,
It ake i t , as ign o f i n teres t i n t he v iewpoin ts o n s ource ma ter ia l a nd r esearch me thods wh ich o ur S cand inav ian mar i t i me work ing g roup h as s e t o u t i n t he b ook S h ips a nd S h ipyards , S a i lors a nd F isher men .
Is hou ld t here fore l ike t o
t ake a s my s tar t ing p oin t t he p apers p ub l ished i n t h is b ook . A s t he t er ms a rchaeo logy , e thnography a nd t rad i t ion a re i n terpre ted i n r a ther d i f feren t ways b y d i f feren t g roups , Is ha l l b eg in w i th a f ew r e marks o n t he mean ing we p lace o n t hese t er ms . Archaeo logy c o mes f ro m t he Greek word a rcha ios , o ld , a nd l ogos , s tudy . S o i t means t he s tudy o f t he p ast .
I n modern t er m inology i tc o mpr ises r e-
s earch i n to t he d eve lop men t o f h u man c u l ture a s r evea led b y r e mains e xcava ted f ro m t he e ar th o r s a lvaged f ro m t he s ea b ed .
T hus a rchaeo logy
u ses q u i te d i f feren t s ource ma ter ia l f ro m t ha t s tud ied i n h istor ica l r esearch , wh ich f ol lows c u l tura l d eve lop men ts ma in ly o r e xc lusive ly t hrough wr i t ten r ecords . E thnography , f ro m t he G reek e thnos , p eop le , a nd g raphein , t o wr i te , s tr ic t ly s peak ing means t he d escr ipt ion o f p eop les .
I n t he I n terna t iona l
D ic t ionary o f R eg iona l European E thnology a nd F o lk lore i ti s d e fined a s
6 5
" the d escr ip t ion o f p eop les , e spec ia lly p r im i t ive p eop les , ad escr ip t ion b ased o n o bserva t ion a nd n o t ing d own o f c u l tura l f ac ts i n t he f ie ld" . S o t he a rchaeo log ist d igs i n t he g round o r d ives t o t he b o t to m o f t he s ea t o f ind h is s ource ma ter ia l , a nd t he h is tor ian f inds h is ma ter ia l i n a rch ives a nd l i brar ies . The e thnographer , h owever , g oes t o t he p eop le t he mse lves i n t he ir n a tu ra l e nv iron men ts , o n l and a nd a t s ea , i n v i l lages a nd t owns , a t h o me a nd i n t he ir f am i l ies , a t t he ir p laces o f work a nd t he ir b usinesses , i n t he ir t ea m g roups o r i nst i tu t ions , i n o rder t o c o l lec t a nd r ecord h is s ource ma ter ia l . H e u ses a v ar ie ty o f me thods a nd a ids .
H e t akes n o tes , h e makes t ape r e-
c ord ings , h e measures , d raws , p ho tgraphs a nd f i l ms .
H e i s g iven p resen ts
a nd b uys o b jec ts a nd d ocumen tary ma ter ia l f or e thnograph ica l museums a nd r esearch i nst i tu tes .
I n s hor t , h e u ses a l l t he means o f c o m mun ica t ion , a l l
t he t rad i t ion med ia wh ich p eop le u se i n t he ir d a i ly work a nd t he ir s oc ia l l i fe . H is f inds a re o f many d i f feren t k inds , b u t i n s p i te o f t h is d iversi ty t he v ar ied s ource ma ter ia l i s c o m mon ly p laced u nder t he h ead ing o f t rad i t ions .
N a tur-
a l ly , l u mping e very th ing t oge ther u nder o ne h ead ing i s h ard ly s a t is fac tory when t he s ource ma ter ia l i s t o b e u sed a s ab asis f or s c ien t i f ic h istor ica l a nd s oc io log ica l r esearch . T here h ave b een l ong d iscussions a i med a t c lar i fy ing a nd d e fin ing more e xac t ly t he n a ture o f t rad i t ion .
I n t he d ic t ionary f ro m wh ich Iq uo ted , wh ich
was p ub l ished i n 1 960 , t here i s ac o l lec t ion o f t he mos t i mpor tan t s ta te men ts o n t h is s ub jec t .
T here i s a lso t he c o m men t t ha t " so me a u thor i t ies u nderstand
e thnography a s as ub-d isc ip l ine u nder a n thropo logy o r e thnology" .
I n f ac t
t hese t wo t er ms a re t he n a mes o f f ie lds o f r esearch more o r l ess s im i lar t o e thnography . Bu t t here i s o ne d i f ference , n a me ly t ha t t hey emphasise t he l a t ter p ar t o f t he word , l ogos , s tudy , r a ther t han g raphein , t o d escr ibe . T h is u nder lines t he f ac t t ha t t hey n o t o n ly d escr ibe p heno mena b u t a lso , a nd a bove a l l , i n terpre t a nd e xp la in t he m b y c o mpara t ive s tud ies a nd t he a na lysis o f t rad i t ions . The d i f ferences b e tween a n thropo logy a nd e thno logy a re n o t s uch t ha t we n eed t o e xa mine t he m h ere a nd n ow .
I ti s s u f f ic ien t t o r e fer t he s tuden t t o
t he b ib l iography l i sted i n t he d ic t ionary . S ince 1 960 t here h as b een a c on t inu ing d eba te o n t h is q uest ion .
Our t ea m
h as t o t he b est o f i t s a b i l i ty c on tr ibu ted a n u mber o f p apers whose f unda men ta l p rinc ip les a re o u t l ined i n o ur b ook u nder t he t i t le The c oncep t o f l i v ing t rad i t ion . Imust o f n ecessi ty r estr ic t myse l f h ere t o c er ta in ma in p o in ts a nd f or t he r es t r e fer y ou t o t he a r t ic le i t se l f . T he word t rad i tion c o mes f ro m t he L a t in v erb t radere , wh ich means t o h and o ver o r t rans m i t .
On t h is b asic mean ing we c an f or mu la te a d e f in i t ion
t ha t c overs t hree ma in p oin ts wh ich a re v i ta l t o o ur d iscussion .
T hey a re
t he c on ten ts o f t rad i t ion , t he b earers o f t rad it ion a nd t he t rad i t ion med ia . The d e f in i t ion i s a s f o l lows : 1 .
Wha t i s h anded o ver c onsists o f e v idence a bou t h uman b e ings , t he ir ways o f l iv ing a nd t he ir a c t iv i t ies .
2 .
T he h and ing o ver - t he t rad i t ion -t akes p lace b e tween i nd iv idua ls , g roups
6 6
a nd i nst i tu t ions ; b e tween d istr ic ts a nd c oun tr ies , a cross c on t inen ts a nd o ceans ; b e tween g enera t ions , o ver d ecades a nd c en tur ies . 3 .
T he e v idence i s t ransferred b y means o f v ar ious k inds o f c o m mun ica t ion -t rad i t ion med ia - s uch a s t he s poken a nd wr i t ten word , p ic tures a nd s cu lptures , a c tions a nd b ehav iour , o b jec ts a nd e qu ip men t ( ar t i fac ts ) , s oc ia l g roups a nd i ns t i tu t ions . T he t rad i t ion med ia a re b y n a ture v ery d issi m i lar .
E ach a nd e very o ne
o f t he m c an f or t h is r eason p ass o n -t rans m i t -o n ly t ha t k ind o f e v idence wh ich i s s u i ted t o i t s n a ture .
B ecause o f t h is we h ave t o d ist ingu ish a t l east
s ix d i f feren t k inds o f t rand i t ion . c a l , 4 Manua l o r v isua l- mo tor ,
T hey a re : 1 Ora l , 5 Ob jec ts ,
2 Wr i t ten ,
3I conograph i-
a nd 6 S ocia l o r I ns t i tu t iona l
t rad i t ion . I n t he a r t ic le The c oncep t o f l i v ing t rad i t ion Ih ave d escr ibed e ach o f t hese t ypes o f t rad i t ion i n d e ta i l a nd a s t ime i s s hor t Imust r e fer y ou t o t h is a na lys is .
Ia lso emphasize i n my a r t ic le a f ac t t ha t we a re a l l a ware o f , n a me ly
t ha t t hose who p ass o n t rad i t ions master t o v ary ing e x ten ts a nd d egrees t he v ar ious f or ms o f e xpression , t ha t i s t o s ay , t he t rad i t ion med ia .
Ano ther
p oin t we a l l a cknow ledge i s t ha t e very p erson who t rans m i ts a t rad i t ion , whe ther c onscious ly o r u nconsc iously , p asses o n o n ly wha t h e h i mse lf f inds wor thy o f t rans m ission o r wha t i ti s w i th in h is i n ters ts t o t rans m i t . E v idence a bou t p eople a nd t he ir a c t iv i t ies w i l l t here fore t end t o b e s i f ted a nd c oloured i n many ways , d epend ing o n t he v ary ing k ind o f t rand i t ion a nd o n t hose who p ass i to n . On t op o f t h is t here i s t he i n f luence t ha t t he i n terpre ters - t ha t i s , t he r esearch workers a nd wr i ters i n t he f ie lds o f h is tory , c u l ture a nd s oc iology -i mpose o n t he e v idence t hey c o l lec t .
A s E .H . C arr , L ynn Wh i te a nd o ther
modern s cho lars h ave p oin ted o u t , i n terpre ters h ave f or many y ears made u se o f o ne-sided , a rb i trar i ly c hosen ma ter ia l wh ich t hey h ave d escr ibed a nd i n terpre ted i n l i ne w i th p reva i l ing d oc tr ines , a nd i n d oing s o h ave u sed t er ms whose mean ing h as n o t b een c lear ly d e f ined . A s we h ave c o me t o a n u nders tand ing o f t h is p rob le m , a nd a s n ew t echn ica l a ids h ave b een i nven ted , more a nd more k inds o f s ource ma ter ia l h ave b een b rough t i n to u se . wr i t ten d ocumen ts .
Archaeo log ists b rough t i n ma ter ia l t h ings t o a dd t o t heir E thnographers t urned t he ir a t ten t ion t o l i v ing t rad i t ions .
On a c loser e xa m ina t ion t hese p rove t o b e o f w ide ly d i f fer ing k inds , n o t o n ly i n f or m b u t a lso i n c on ten t . T hey a lso d i f fer i n t he ir d istr ibu t ion b o th among v ar ious p r im i t ive p eop les a nd among v ar ious g roups i n o ur own s oc ie ty . Is uppose t ha t l anguage i s t he t rad i t ion med ium t ha t most c lear ly d iv ides u s i n to d i f feren t t rad i t ion g roups . A s y ou c an a l l h ear , E ng l ish i s n o t my mo ther t ongue , a nd Is o me t i mes f ind i td i f f icu l t t o make myse l f u nderstood i n e very d e ta i l i n a n Eng l ish-speak ing c o m mun i ty . T he s a me i s t rue when p eop le f ro m d i f feren t s oc ia l c lasses o r o ccupa t ions h ave t o c o m mun ica te w i th e ach o ther .
L e t me i l lus tra te t h is p oin t w i th a s tory t o ld b y t he f a mous S wed ish
wr i ter A lber t E ngs tröm .
I tc o mes f ro m t he i s lands o u tside S tockhol m - t he
S tockho l me s k i irgard , a s i ti s c a l led . g ues t f or t he s um mer .
Af i sher man t here t ook i n ap ay ing
T h is g ues t was a l and lubber , b u t h e wan ted t o t aste
t he j oys o f t he o cean wave , s o h e d ec ided t o t ake s ai l ing l essons. 6 7
T he
f isher man b egan t he f irs t l esson : " Supposing I 'm o n as tarboard t ack , a nd wan t t o ... " " S top . S top . Wha t o n e ar th a re s tarboard t acks?"
" Hm ..
I fy ou 're s o b loody u neduca ted y ou d on 't k now wha t as tarboard t ack i s , t here 's n o p oin t i n t a lk ing t o y ou ." And t ha t was t he e nd o f t ha t l esson . I n t he t h ir t ies t hose o f u s who were work ing a t t he G o thenburg Museum were o f ten f aced w i th p rob le ms o f t h is k ind .
Dur ing t he s u m mers we were
o u t o n a rchaeo log ica l a nd mar i t i me e thno log ica l f ie ld e xped i t ions i n t he p rov ince o f B ohusl t in a nd t he s urround ing d istr ic ts a long t he S kagerrak a nd t he N or th S ea .
T hen we s pen t t he w in ter a na lys ing t he ma ter ia l we h ad c o l lec ted a nd
r esearch ing i n a rch ives a nd l i brar ies .
We s oon d iscovered t ha t we h ad t o
c o m mun ica te w i th o ur f r iends o u t i n t he f ie ld w i th d i f feren t t rad i t ion med ia f ro m t hose we u sed w i th o ur l earned c o l leagues i n t he wor ld o f b ooks .
We
f ound , t oo , t ha t l i v ing , o ra l a nd manua l t rad i t ions were b es t f or e xp la in ing t he f unda men ta l p r inc ip les o f t he b oa t a nd s hipbu i lders , t he ir p rocedures , me thods o f c on truc t ion a nd ways o f t h ink ing .
A nd t hey v ar ied e nor mously
b e tween t he l arge a nd t he sma l l s h ipyards , a nd b e tween t he c l inker a nd t he c arve l b u i lders .
Wha t was s e l f-ev iden t g ospe l t ru th among t he f or mer c ou ld
n ot e ven b e t hough t o f among t he l a t ter .
I n f ac t i t was j us t t hese c on trad ic-
t ions t ha t g ave u s o ur mos t s a lu tary l essons i n t he a r t o f u nders tand ing a nd i n terpre t ing t he e v idence o f o b jec ts , d raw ings a nd o ther t rad i t ion med ia .
I t
was t hese c on trad ic t ions t ha t d rew o ur a t ten t ion t o t he h ear t o f t he p rob le m i n s h ipbu i ld ing r esearch , t he f unda men ta l d i f ferences b e tween s he l l a nd s ke le ton c onstruc t ions , b e tween c l inker a nd c arve l b u i ld ing . T hese d i f ferences h ave , o f c ourse , b een men t ioned i n af ew b ooks o n s h ip-bu i ld ing , b u t t hey h ave n ot b een d escr ibed i n d e ta i l a nd h ave c er ta in ly n ever b een a ccura te ly d e f ined . We p ub lished s o me o f o ur e xper ience a nd i deas i n af ew s hor t p re l im inary e ssays i n S wed ish j ourna ls .
Ac oup le o f t hese were t rans la ted i n to Eng l ish
i n F ondly , 1 958 a nd Mar iners Mirror , 1 963 a nd a t trac ted t he a t ten t ion o f i n terna t iona l b oat a rchaeo log is ts who , w i th t he h e lp o f n ew t echn ica l a ids , h ad s ucceeded i n i nvest iga t ing a who le s er ies o f wrecked s h ips.
T he ir f inds
h e lped t o t hrow n ew l igh t o n f ie lds wh ich h ad p rev ious ly b een s ad ly n eg lec ted . I n av a luab le a r t ic le o n Anc ien t wrecks a nd t he a rchaeo logy o f s h ips i n T he I n terna t iona l J ourna l o f N au t ica l Archaeo logy a nd Underwa ter E xp lora t ion , 1 972 , Mr . L uc ien Basch h as p resen ted a l ucid s urvey o f t he r esearch i n to t he h istory o f s h ip-bu i ld ing , p r inc ipa l ly i n t he Med i terranean a rea d ur ing a n t iqu i ty.
H e i nc ludes a we lco me d iscussion o f t he c oncep ts o f s he l l a nd
s ke le ton c onstruc t ion , c l inker a nd c arve l b u i ld ing , wh ich mos t s cho lars a nd wr i ters u p t o t hen h ad t rea ted f ar t oo s uper f ic ia l ly . t hese t er ms e ven more p recise ly d e f ined .
I ti s i mpor tan t t o g e t
F or tuna te ly t he d iscussion h as b een
t aken u p b y Mr . Arne-E m i l C hr is tensen i n a mos t r eadab le a r t ic le i n t he s a me j ourna l i n 1 973 . Ih ave n o t ime h ere , u n for tuna te ly , t o g o d eeper i n to t hese p rob le ms , b u t Iwou ld men t ion t ha t Ih ave t ouched u pon t he m i n s evera l e ar l ier e ssays , a nd more r ecent ly i n t he a rt ic le Ma in P r inc ip les i n t he T echno logy o f S h ip Bu i ld ing , wh ich Mr . B asch h as e v iden t ly n o t r ead .
There a re , i n f ac t , many
p rob le ms i nvo lved , s uch a s v ar ious me thods o f c ons truc t ion a nd t he ir v ar ian ts a nd h ybr id f or ms ; t he u se o f d i f feren t me thods o f f asten ing t he p lanks t oge ther , 6 8
t o t he f ra me a nd t o t he k ee l , t he u se o f mode ls , t e mp la tes , i ns trumen ts , d raw ings a nd o ther a ids ; n o t t os peak o f t he v ar ious k inds o f t oo ls , e qu ip men t , c usto ms a nd b usiness o rgan isa t ion , a l l o f wh ich p lay v ery i mpor tan t r oles. O ther s peakers , i n t h is s y mposium Iam s ure , w i ll d ea l w i th s uch ma t ters i n o ther c on tex ts . My f unc t ion a t t h is c on ference i s ma in ly t o r em ind y ou o f t he p ar t t ha t e thnography a nd l i v ing t rad i t ions c an p lay i n mar i t i me a rchaeolog ica l r esearch . Ih ave p o in ted o u t t ha t o ur t ea m h as l i sted s ix s uch t rad i t ions , a nd t ha t t hose wh ich a re t rans m i t ted o ra l ly , manua l ly o r b y v isua l- mo tor means p ar t icu lar ly warran t t he d escr ip t ion l i v ing a nd d eserve s pec ia l ly c lose s tudy . May Ia lso p o in t o u t a ga in t ha t i ti s t hese t rad i t ions t ha t h ave p rov ided t he c leares t a nswers t o t he p roble ms t ha t Mr . B asch h as r a ised . B u t t hey d o h ave o ne weakness , ac ons iderab le o ne .
T he s poken word d ies r ap id ly .
p a t terns o f b ehav iour a lso d isappear .
H and move men ts a nd
Bu t t hey a re r epea ted i n more o r l ess
s tereo type f or ms. And wha t i s more , t hey f orm t he b asis o f o r a re man i fested , b eco me t ang ib le a nd t ake c oncre te f or m i n o b jec ts a nd t h ings - s h ipwrecks , d raw ings , wr i t ten d ocumen ts , o rgan isa t ions a nd i ns t i tu t ions a nd s o o n . And t hese l i ve o n t hrough t he c en tur ies . T he e phe mera l words , move men ts a nd t urns o f t he h and a re p reserved i n t he m . D ead a nd v o ice less t h ings b ear w i tness o f t he ir c rea tors , a nd h ow t hey s poke a nd worked , l i ved a nd b e l ieved . T hey , t oo , a re t he b earers o f l i v ing t rad i t ions , f ix ing t he m i n t ime a nd s pace . T hey p rov ide u s w i th f ixed p oin ts f or o ur r esearch a nd a ccoun ts o f c u l tura l d eve lop men t , i n wh ich t he a r t o f s h ip-bu i ld ing h as p layed a h igh ly s ign i f ican t r o le .
6 9
F ig . 8 .1
S he l l c onstruct ion .
C l inker b u i ld ing w ith o ver lapp ing p lanks.
a .
T he k ee l a nd t he l ower p ar t o f t he s te m a re h ewn o ut o f t he
b .
r oo t e nd o f as pruce. The k ee l i s r ough ly o u t l ined i n t he f ores t .
c .
T he k ee l i s s haped w ith a n a xe i n t he workshop.
d .
T he u pper p ar t o f t he s te m i s n a i led t o t he l ower p ar t ( i n o ne
e .
p ar t w ith t he k ee l ). T he f irst p lank i s p u t i n p os it ion.
f .
T he s econd p lank i s p u t i n p os it ion .
g .
The t h ird p lank i s p u t i n p os it ion .
h .
A l l t he p lanks a re i n p os it ion .
T he b oat s he l l i s ' bordfy l lt '
( co mp leted ). i .
Wood f or f ra mes i s c hosen i n t he f orest .
j .
Af ra me i s h ewn i n t he workshop.
k .
Af ra me i s f i t ted t o t he h u l l.
4,
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F ig . 8 .2
S hel l c onstruct ion.
Boa ts b u ilt w ith smoo th s ides , p lanks j o ined
e dge t o e dge. c .
P lank ing t e mporar ily h e ld t ogether w ith c la mps. Amsterda m 1 670.
d .
Draw ing b y S ieur Arnou ld.
Fr is ian y aw l i n S ta .voren 1 955.
B ibl. Na t. P ar is.
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S hel l c onstruct ion .
Boats b u i lt w i th smooth s ides , p lanks j o ined
e dge t o e dge. a .
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b .
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F ig . 8 .3
S he l l a nd S ke leton Cons truct ion c o mb ined . T he h u l l b e low t he water l ine i s c l inker b u il t . Above t he wa ter l ine i ti s c arve l b u i lt o n ar ib-fra me. A g a leas u nder c ons truct ion 1 938. K ongsv iken , Bohus län , Sweden .
r.
. ; „
F ig . 8 .4
S ke leton c ons truct ion . -T hree t ypes o f h a lf mode l. Most o f t he s h ipbu i lders who b u i lt t he m idd le-s ized a nd sma l ler s a i l ing v esse ls c ou ld n ot make s h ips d raw ings.
T hey b u i lt t he ir
c arve l s h ips f ro m b lock mode ls , w h ich t he s h ipwr igh t made i n c o l labora t ion w ith e xper ienced s eamen i ncorpora t ing a l tera t ions a nd a dd it ions t hey c ons idered a dvan tageous.
S o me s h ipwr igh ts c u t
s uch a model o ut o f as o l id b lock a nd s awed i tv er t ica l ly i n to t he s a me n u mber o f s l ices a s t here w ere t o b e c ons truct ion r ibs. r ibs a re t hen mode l led o n t hese s l ices.
T he
I nstead o f s aw ing t he
mode l u p , a no ther method i s t o u se a l igh t l ead r od t o make i mpress ions t ha t w il l g ive t he s hape o f t he r ibs.
O ther b u ilders p in
t ogether i n to a b lock h or izon ta l l ayers o f w ood whose t h ickness i s s haped t o t he wa ter l ines o f t he p lanned s h ip .
T he h a lf- mode l i s
t hen c u t o u t o f t he p inned b lock a nd t he s l ices a re t aken o u t a nd measured t o g ive t he s hapes a nd s izes o f t he a c tua l r ibs. 7 6
9 .
THE XAVEGA BOAT
A CASE STUDY I N THE I NTEGRATION OF ARCHAEOLOG ICAL AND ETHNOLOG ICAL DATA O ctav io L ixa F i lgue iras S um mary D iv ision o f P or tuga l b y t he D ouro : t o t he N or th , e ar ly S cand inav ian/Ger man ic ( r iver c ra f t ) a nd B re ton ( i nshore f i sher ies ) i n f luences ; t o t he S ou th , Med i terranean i n f luences . T he S ave iro ( t he most s igni f ican t b oa t i n t he S ou th r eg ion , f i sh ing w i th t he x avega s e ine ) a s ma in v ector o f t he o ldest Med i terranean i n f luence : Mesopo ta m ian o r ig in - s tr ik ing i den t i ty ( f or m a nd t echn ica l ) w i th a ncien t U r c ra f t s t i l l s urv iv ing i n t he L ower Euphra tes , T he Ur t o Ugar i t ( v ia Euphra tes , A leppo , A la lakh ? ) t rade r ou tes a s p ossib le v eh ic le t o t he Med i terranean , I conograph ic e v idence ( Cre tan s ea ls , H ag ia T r iada p a in t ing , p ossib ly T hera mura ls) o f i t s p resence i n t he A egean , D ocumen ted wes twards p rogression , S urv iva l o f s im i lar c ra f t i n I t a ly . T he p rob le m o f t he e thn ic o r ig in o f t he c o m mun i t ies f i sh ing w i th t he s ave iro : T he ir p ecu l iar i ty , C o-incidence o f t he a reas o f d istr ibu t ion o f t hese b oa ts a nd t he ma in a reas o f r e fuge o f S ou th I ber ian p eop les a f ter t he f a l l o f T ar tessos , T he o pen q uest ion o f C re tan i n f luence i n Tar tessos . T he a bove p roposed s ources f or t he s ave iro a s an ew f ac tor f or t he r e-eva lua t ion o f t hese a rgu men ts. Due , p erhaps , t o t he d i f feren t e nv iron men ta l c ond i t ions p reva i ling N or th a nd S ou th o f t he D ouro , t h is r iver h as t rad i t iona l ly marked t he b order b et ween d i f feren t e thn ic o r t r iba l g roups a nd c on trast ing c u l tures : Lusi tan ians , B racar i/Turdu l i ,
1
G a l ic ians/
C hr ist ians/ Mus le ms ,
S uch a d iv is ion i s s t i l l a pparen t t oday i n t he d istr ibu t ion o f o ur v ernacu lar b oa tsA b u t S trabo h ad a lready r epor ted t he n av iga t ion o f t he D ouro b y l ea ther c ra f t ' ( t he u se o f s uch c ra f t i s o f ten i nvoked a s a n i mpor tan t c r i ter ion i n d ist ingu ish ing N or th European f ro m Med i terranean c u l tures ) b r inging t o mind t he p ossib le c onnect ions b e tween G a licians a nd Oestr i mn i i , o f who m Av ienus s ang :
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i ti s s ugges ted t ha t t he r esu l ts o f e ach b ra in s ession s hou ld b e j o t ted d own . D i f f icu l t , b u t l ess f rus tra t ing t han t o n urse a s usp ic ion t ha t o ne i s f orge t t ing s o me i mpor tan t e ar l ier c onc lusion . Work ing o u t a l l t he p oss ib le v ar ia t ions , h owever f ar f etched , i s t he n ex t s tep o n f ro m p ipe d rea ms . T h is n eeds t o b e d one s ys te ma t ica l ly o n p aper , s o a s t o l eave n o g aps i n t he l i st o f s tar ters.
I t migh t h e lp t o s how wha t i s
mean t , i f Ig ive a n e xa mp le f ro m t he Graveney B oa t ( The G raveney B oa t e d i ted b y V .H . F enw ick , f or thco ming ) . o n ly e nough t o d e f ine t he v ar ia tions .
A ctua l ly t he work ing s ke tches were
T h is p ar t icu lar p rob le m was t o work
o u t t he f or m o f t he s tern , t he u pper p ar t o f wh ich was a bsen t ( F ig . 1 5.1 ). The s ternpos t r aked a l o t a nd t he r e ma in ing f ew p lank e nds were r a ther w ide . T en t o ad ozen s trakes h ad t o b e a cco m moda ted , a nd i ft h is was t o b e d one w i th w ide e nds a l l t he way u p , t he s ternpost n eeded t o b e v ery l ong .
A s t here
were r eserva t ions a bou t o verhangs a l most a s l ong a s t he k ee l , t hese a re s o me o f t he s tra igh t s ternpost v ar ia t ions t ha t were t hough t o u t a nd c onsidered :A .
W ide p lank e nds a s d escr ibed a bove ,
B .
N arrow p lank e nds w i th r ope woo ld ing ,
C .
T ransverse l anding t imber f or i l pper s trakes ,
D .
Washs trakes t o g a in f reeboard am idsh ips , a nd
E .
R unn ing t he u pper s trakes o f f t he s heer l ine .
S ome o f t hese were d ropped e ar ly o n , wh i le o thers were k ep t a s s t i l l workab le . As l ike p rocesses were b e ing a pp lied t o t he o ther s truc tures , i t was f ound s o me v ar ia t ions h ad t o b e r u led o u t a s t hey d id n ot f i t e lsewhere .
T h is s howed t he
v a lue o f af u l l l i s t o f v ar ia t ions a t t he s tar t ; a s w i thou t i t , t he e l im ina t ion o f n on-runners t akes l onger . T he c onserva t ion a nd r easse mb ly o f wha t h as b een r ecovered i s a n i nv a luab le s tep t owards r econs truc t ion .
The f ind a nd t he r ecords made d ur ing
a nd a f ter t he e xcava tion a re n ot o n ly t he a rch iva l s tar t ing p oin t o f o ne 's own , b u t w i l l b e o f o ther i nves t iga t ions .
H app i ly mos t o ld s h ips a re h e ld t oge ther
b y imper fec t ly s paced f asten ings , wh ich t hus o f fer a n e xc lusive s o lu t ion f or r easse mb ly . D is tor t ion , b efore a nd a f ter t he e xcava t ion , l owers t he v a lue o f t he r e-asse mb ly u n t i l t he d endro log ica l a nd c onservat ion e xper ts d etect a nd q uan t ify i t .
Th is a nd mak ing a l lowances f or s hr ink a nd t w is t w i l l t ake
t ime a nd d e lay p rogress.
However , a n e ar ly a ssess men t c an b e made f ro m
t he l oss o f s hape i n b ored h o les , a nd f ro m p itch e rrors b etween p a ired r uns o ff as ten ing h o les. A f ter a s he l l h as b een s t i tched t oge ther i ti s s t i l l n o t as ing le-shaped r ig id s tructure ( F ig . 1 5.2 ). S ur faces made u p o f p ieces whose e dges a re s tra igh t o r a n e xac t ma tch a re e ither f la t , c y l indr ica l o r c on ica l i n f or m. F orms t ha t a re b u i l t o f p ieces t ha t h ave c onvergen t o r d ivergen t c urves b eco me more r ig id a s t hey a pproach a c o mp le te s phere . Opened t opped f or ms l ike t he s he l l o f as h ip r e ma in f lex ib le u n t i l f ixed b y s o me d i mension a cross o r a long i t s l eng th .
A s d raw ing t echn iques f or d oing t h is a re p onderous a nd p robab ly
s ub jec t ives , mode ls a re p re ferred . Ex trapo la t ion b y s o me means o r o ther may b e u sed t o d iscover t he s hape o f t he missing p ar t o f t he h u l l .
F irst ly a l ot d epends o n wha t c an b e d educed 2 09
a bou t t he o r ig ina l b u i lder 's me thods , a nd t hen , whe ther o r n o t h e wen t o n u sing t he m .
F or c er ta in p er iods i n t he p as t we h ave e xa mp les o f u nderwa ter
p ar ts o f av esse l a s we l l a s p ic tures o f t he u pperworks o f c on te mporary s h ips . S cru t iny w i l l s uggest whe ther a ma tch h as b een f ound , a nd i fi th as , h ow much more h u l l b u i ld ing i s n eeded b e fore t he t op h a mper s tar ts .
Ex terna l f ea tures
c a l l f or l oca l i n terna l s t i f fen ing , a nd t he c onverse i s a lso t rue .
R e la t ing t he ' N
f ind t o p ic tor ia l e v idence c an b o th e xp la in wha t y ou h ave a nd s uggest where t he t opsides , c apstans a nd s pars t ha t y ou h aven 't , were o r ig ina l ly . Wood b ends i n to s tra igh t forward s hapes a nd r es ists c o mp lex o nes , b y b reak ing s ooner o r l a ter . ma the ma t ica l r u les .
S wee t wooden c urves a nd musica l h ar mon ics f o l low
Wh i le s h ipwr igh ts n o more k new t hese r u les t han a b oy
h um m ing a t une ; t hey c an h e lp w i th e x trapola t ion .
The s p l ine i s a n a na logue 4 .
f or d oing t h is , b u t i ti s n o t a s o b jec t ive a s d o ing s tuns . T he u se o f ma the ma t ics o f ten g enera tes r esistance ; maybe f ro m a s uspic ion i ti s a n a t te mp t t o h oodw ink .
I n t he f ie ld o f a rchaeo logy , o ne h as t o d epend
aga in a nd a ga in o n t he f ind ings o f as pec ia l ist , whose e xper t ise o ne c ou ld n o t ma tch .
Wha t t hen i s s o b ad a bou t t he ma the ma t ic ian?
i fo n ly t o g e t t he r igh t a nswer .
H e h as t o b e h onest ,
More u se s hou ld b e made o f t he ir t a len ts .
I fi ti s t hough t t ha t ma the ma t ica l p roo fs w i l l b e u naccep tab le , t hen i t may b e w iser t o k eep t he m u nder t he b lo t ter .
T hey w i l l b e af ine g u ide , b u t y ou w i l l
h ave t o f ind a nother way o f u npho ld ing y our s o lu t ion . H ere a re t wo c ases where s ums h e lp .
One c urve i s o f ten s een i n b oa ts .
Though i th as a r a ther g rand n a me , r ec tangu lar h yperbo la , i tc an b e d rawn ; f irs t b y as er ies o f r ec tang les a l l t he s a me a rea w i th a c o m mon c orner , t hen r unn ing a l ine t hrough t he o pposi te c orners.
I fy ou f ind a l i ne t ha t i s c urv ing
l ike t h is , a nd y ou c onsider t ha t t he n a ture o f i t was n o t c hang ing ; y ou c an work o u t t he r est o f i t .
T he s econd a id i s at ab le o f d i f ferences , a nd t he h and
h e ld c a lcu la tor h as t aken t he d rudgery o u t o f u sing i t .
H ere y ou s tart b y mea-
s ur ing s o meth ing a t e qua l i n terva ls , s ay , t he h e igh t o f as trake e very metre. Wr i t ten d own , y ou h ave a r ow o f f igures. N ow i n t urn t ake e ach f igure f ro m t he o ne n ex t t o i t , a nd t h is g ives t he r ow o f f irs t d i f ferences .
I ft hey c o me
o u t t he s a me o r t o lerab ly s o , t hen t he s trake i s s tra igh t b u t s loping .
I fn ot
t he s a me , y ou work o u t t he r ow o f s econd d i f ferences a nd s o o n t i l l t hey a re . I fa f ter t he t h ird o r f our th t ime t h is d oesn 't h appen t he c urve i sn 't f a ir , b u t y ou c an make i ts o b y a d jus t men ts i n t he l as t r ow o f d i f ferences a nd a dd ing b ack . I fo r when t he r ow o f d i f ferences i s t he s a me y ou c an e x tend t he c urve o r f i l l i n a ny g aps. Y ou c an r ead more a bou t t h is v ersa t i le t echn ique ( Ma the ma t ics w i th a Desk C a lcu la tor b y R .H . C obb , G . B e l l &S ons , L ondon , 1 970 . C hap . V . T abu la tion o f E qua l D i f ferences .) . E stabl ish ing b u i lding me thods i s more a bou t t he s ize a nd s ort o f t he s truc ture t han t he o vera l l s hape j ust d iscussed .
My own t hough ts g o a s f o l lows .
T rad i t iona l B r i t ish b oa tbu i lders u se s i mp le r u les o f t hu mb t o g e t t he ir s izes . They may u se r e la t ionsh ips s uch a s o ne t h ing b e ing t w ice a s l ong a s a no ther , o r c onversions s uch a s t he c ircum ference o f as par b e ing t he s a me n umber o f h al f i nches a s i t s l eng th i n f ee t , a nd t here a re r u les f or s can t l ings , s pac ing o f f asten ings e tc ..
Exa m in ing a f ind may r evea l s o me o f t hese r u les .
F or
i nstance , i ft he b u i lder was s pac ing h is l ower f asten ings a t s i x t imes t he p lank t h ickness , h e migh t we l l u se t he s a me r u le f or t h inner p lank ing h igher u p .
2 10
EN IGMAS— Wha t
a re
t hese
f ea tures?
E as t W indow M a lvern P r io ry C hu rch
G ammon ing
1 2 th C en tury E ng l ish
B rev iary
B ad ly d rawn R obands
N orman S h ip B ayeux T apes try
S a i l d oub led o ve r y ard P e fo ra ted L ea the r S a i l
B owe S es inges S co tsman f o r C ab le F o res tage L ash ing E nd o f F o res tay B itted C ab ie
S qua re -sa i l w i th c lues m o r r ie c L a teen-sa i l w i th
t ack t ree
B ad ly d rawn S quare -sa i l
F ig. 1 5.3
En ig mas.
One o f ten f inds t ha t t o-day 's r u le f i ts a n a nc ien t b oa t , b u t i t wou ld b e wrong t o a ssume t h is was a lways s o . T ex t b ooks a nd o ther c on te mporary s ources b eco me more r e l iab le a f ter t he 1 6th c en tury .
B y t hen more a nd more o f t he s h ip 's d i mensions were
f rac t ions o f o thers , s o , i n t heory , o ne c an w ork o u t ac o mp le te d esign f ro m v ery l i t t le i n i t ia l e v idence .
One h as , h owever , t o b e c er ta in t ha t o ne h as t he
r igh t t ex t b ook a nd b e c onv inced t ha t t he b u i lder h ad f o l lowed i t ; t wo r a ther s t if f c ond i t ions.
W.A. B aker 's a r t ic le a bou t h is d esign f or May f lower I .
( Amer ican N eptune , J an .
& Oct . 1 954 ) i s a n a b le a ccoun t o f t h is me thod .
C on te mporary mode ls a nd d ra f ts mus t b e c hecked t o s ee i ft hey a re o n ly p ro jec ted d esigns , o r c ock s h ies t he mse lves .
S uch mode ls were c onstruc ted
t o ac onven t ion r a ther d i f feren t f ro m r ea l p rac t ice . B e fore t he t ex t b ooks , t here were f orma l r epor ts , b u i lding a ccoun ts a nd s h ip i nven tor ies .
These c a l l f or s o me d egree o f s cho larsh ip t o u nrave l , b u t
t here a re f ine e xa mp les t o b e f ound i n t he Mar iner 's Mirror . g leaned b y t hese means ;
Much c an b e
wha t l i t t le i s k nown a bout t he s ize o f t he G o lden
H ind a nd A then ian Tr ire mes i s b ased o n h ow t hey were h oused . ( Mar iner 's Mirror , 3 5 p . 5 6 , a nd Anderson , Oared F igh t ing S h ips , Chap. 2 ). C on te mporary p ic tures c ou ld t e l l al o t i fo ne was s ure wha t t he s h ip was , a s we l l a s where a nd when s he e x is ted .
I ti s h ard t o s ay a s t hese i l lus tra t ions
were c opied a nd u sed a ga in q u i te o u t o f t he o r ig ina l c on tex t , j ust l i ke t o-day . They n eed t o b e l ooked a t more f or t he q uer ies t hey p ose t han t he a nswers t hey p rov ide . H ere a re t hree we l l k nown d e ta i ls , a s y e t Id o n o t k now o f as a t isf actory e xp lana t ion f or t he m ( F ig . 1 5.3 ). The t r iangu lar s a ils i n t he Bayeux Tapes try ; t he r opes r ound s te m h eads ; a nd t h is way o f s ecur ing s a i ls t o t he ir y ards . Whe ther t he a nswers t o s uch q ues t ions a re n eeded b e fore o ne s tar ts t q r econs truc t , o r w i l l c o me o u t a s ar esu l t o f i t , i s ab i t l i ke a sk ing i ft he h en o r t he e gg c a me f irst . I n terpo la t ion o f e x ist ing k now ledge i s h elp fu l when t he d esigns o f v esse ls b e fore a nd a f ter h ave b een we l l e stab l ished . T h is s t i l l c a l ls f or a s ta ted a ssump t ion , a s o ne c ou ld e as i ly a rr ive a t as ca le o f s pur ious t ypo log ica l d a tes t h is way . Av esse l mus t s tay a f loa t a nd u pr igh t l ong e nough t o make e ach t r ip . These a b i li t ies c an b e worked o u t , b u t we h ave t o a ssume t ha t t he s a fe ty s tanda rds were p robab ly l ess t hen t han n ow .
T hese c a lcu la t ions c an b e u sed t o
d eve lop a l terna t ives a s we l l a s t es t ing t he m , a nd a re e ssen t ia l i n e very r ec onstruc t ion . E ven tua l ly o ne a rr ives a t as hor t l i st o f r easoned s o lu t ions .
Whereas ,
u p t i l l t h is s tage much o f t he work w i l l h ave i nvo lved v ar ious i nd iv idua l 's s e lec t ion o ugh t t o b e b y ag roup o f t he mos t u nb iased p ersons o ne c an a sse mb le . I n a dd i t ion t o mak ing t he ir c hoice , t hey s hou ld b e a sked t o r eco m mend h ow f ar t he r econstruct ion s hou ld g o o n f ro m t here .
A s t he t ime t hey w i l l h ave t o
s pare w i l l b e l im i ted , i ti s n ecessary t o t ake t roub le o ver p resen t ing t he r es u l ts o f t he i nvest iga t ion t o t he m . Mode ls make f ine c ock s h ies , a s t hey c an b e a ssi m i la ted more e asi ly t han a ny o ther r epresen ta t ion . a l terna t ive mode ls .
They c an b e h and led a nd c o mpared s ide b y s ide w ith
T o me , c onven t iona l d rawings a re h ard t o i n terpre t ; a nd 2 12
a s much a s a r t is t ic work p leases , i tc an a lso mislead . A mode l mus t p resen t a n a l terna t ive c lear ly a nd a ccura te ly , b u t g o o n f ur ther . L ike a l l g ood f or ms o f c o m mun ica t ion i tw i l l t ake l onger t o make t han u nderstand ; b u t i tw i l l g e t t he u se fu l r esponse o ne s e ldo m g e ts b y o ther me thods . B y t he t ime t ha t ad ec is ion h as b een r eached t o embark o n af u l l s ize r ep l ica t he r e ma in ing a l terna t ives s hou ld h ave b een n arrowed d own e nough t o b e t r ied o u t i n as ing le h u l l , u sing mock-ups b e fore f ina l ising a t t imes . T he l essons l earn t f ro m t he b u i ld ing a nd t r ia ls s hou ld n ot s how o ne h as f rozen t he d esign t oo s oon .
A t t h is o r s o me e ar l ier s tage i t may b e d ec ided t o p ub l ish
t he r econstruc t ion , e i ther a s p ar t o f ar epor t , p lans f or a mode l o r i n t he c ourse o f r a ising f unds .
A s i n med ieva l t imes s uch d raw ings a re s ure t o
r eappear o u t o f c on tex t .
S o , t h is i s ap lea t ha t a ny r econs truc t ion d raw ings
s hou ld i nd ica te h ow s er iously t hey s hou ld b e t aken ; t er ms l i ke T en ta t ive , S econd o f F our I n ter im P ossib i l i t ies o r P re ferred D esign f or R ep l ica t oge ther w i th a d a te migh t mee t t he c ase . Y ou c an s ee t ha t t here i s ac hoice o f me thods. Appropr ia te ly u sed a nd i n t he r igh t o rder t hey g o t owards d eve loping a r econs truc t ion , b u t o n ly i ft he i n i tia l r ecord a nd e xa m ina t ion was p roper ly d one . I t wou ld n o t b e f a ir t o l e t y ou l eave w i th t he i mpression t ha t Ih ave d one a l l t h is , b u t Id o w ish Ih ad . I ti s t hough t t ha t a l l t he p oss ib le Graveney a l terna t ives were c onsidered , b u t i t wou ld n ot b e e asy t o s ay h ow e ach was s or ted o u t . The o pen ing s tory h as o ne l as t p oin t ; e ven a p oor ly p resen ted r econstruc t ion may s t i mu la te f ur ther r eseach . T h is i s n o t s a id t o e ncourage more i l l-cons idered r econstruc t ions. T here a re e nough o f t hese , w i th d amage s t i l l t o b e u ndone . I nstead , o ne wou ld l i ke t o h ear o f more work b e ing d irec ted t owards ah igher d egree o f h ypo the t ica l r econstruc t ion .
Once s uch a h ypo thes is h as
b een worked o u t , p resen ted , d iscussed a nd a ccep ted , r econstruc tion s hou ld f o l low . T hen , i ff unds h ave t o b e f ound , i ts hou ld b e p ossib le t o s how t ha t t he g round work h as b een s ound .
2 13
1 6 .
HYPOTHETICAL RECONSTRUCT IONS AND THE NAVAL ARCH ITECT J . F . C oa tes S u m mary
Eng ineers l ook a t a r t ifac ts a nd d esign p rob le ms i n t er ms o f p urpose t o b e s erved , p r inc iple a nd c ircumstances o f o pera t ion , c os t , work ing l i fe a nd r epa ir .
An ava l a rch i tec t t ends t o a pproach
p rob le ms o f b oa t a nd s h ip r econs truc t ion i n as im i lar way w i th p ar t icu lar c oncern a bou t l oads c arr ied , s treng th , wa ter t igh tness , s tab i l i ty , p ropu ls ion , s peed , r ange a nd s eawor th iness .
L ack o f
d a ta c an p reven t a ny o ne r econs truc t ion f ro m b e ing p roven c orrec t , when s evera l s hou ld b e d eve loped a nd s us ta ined i np ara l le l . S o me Bronze Age b oa t f inds a re t aken t o i l lustra te t he v ar ie ty o f f or ms a nd q ues t ions t ha t c ou ld o ccur t o an ava l a rch i tec t i n p onder ing t he r econs truc t ion o f s can t r e ma ins . B ecause b oa ts h ave b een e vo lved , r e ma ins f ound a re l i ke ly t o b e o f s uccessfu l d esigns , b u t h ypothe t ica l e le men ts o f r econs truct ions n eed a ssess men t b y n u mer ica l a na lyses o f s treng th , s tabi l i ty , s peed , p ower a nd s eakeeping .
L oads s hou ld b e p os tu lated a nd water-
t igh t s treng th o f j o in ts c hecked . N o r econstruc t ions o f a n u n fa m i l iar c ra f t c an b e a ssu med t o b e s a t isfac tory w i thou t e xa m ina t ion o f we igh t a nd s tab i l i ty , i nc luding s tab i l i ty i n f ace o f l eakage .
The p er for mance o f ah ypo the t ica l
r econstruc tion i s u ncer ta in u n less a r ep l ica h as b een a c tua l ly b u i l t a nd t ested .
B e ing a n ava l a rch i tec t Ih ope t o b e f org iven i f Il ook a t t he c rea t ion o f h ypothe t ica l r econstruc tions f ro m t he v iewpoin t o f a n e ng ineer r a ther t han t ha t o f a n a rchaeo log is t .
Eng ineers t end t o s ee a r t i fac ts a nd d esign p rob le ms
i n t er ms o f q uest ions l ike :Wha t i s i tf or? H ow w i l l i t work?
Where?
H ow t o make i t? H ow much w i l l i tc ost? H ow t o o pera te i t?
C an i tp ay i t s way?
Who i s t o o pera te i t?
H ow l ong must i tl ast?
C an i tb e r epa ired?
Wha t w i l l t he n e ighbours s ay a bou t i t? 2 15
T hose r a ther s i mple , e ven o bv ious , q ues t ions c ou ld b e d ressed u p i n h igher f l own t er ms , l i ke s ys te m , e nv iron men t , t echno logy , a nd s o o n , b u t h owever e xpressed , t hey a re u navo idab le i n e very p ro jec t t oday . T hey were n o l ess =avo idab le i n t he p as t , a nd c er ta in ly i np ro jec ts l i ke b oa ts . I nt h ink ing t here fore a bou t a ny r econs truc t ions , i nc lud ing r econstruc t ions o f b oa ts , o ne h as t o f ind g ood e ng ineer ing a nswers t o t he s a me q uest ions a lbe i t i n ad i f feren t t ense . E ach r a ises a c o l lec t ion o f i n terwoven i ssues a bou t a ny r econs truc t ion :Wha t was i tf or?
T ranspor t
G oods
War
P eop le
T ype o f S oc ie ty
T hrea t
G eography
P rest ige
E cono my
T rade
Opera t ion?
Work ing l i fe E cono m ics o f Ownersh ip Va lue a nd c ost o f o pera t ion S ocie ty
H ow was i tb u i l t?
Ma ter ia ls -f orm ing , o r ig in , g eography
H ow r epa ired?
T oo ls - s k i l ls - S oc ie ty E f for t -c os t -t ime t aken
H ow w i l l i t work?
L oads
S treng th
S tab i l i ty C on tro l S eawor th iness C rew Wa ter t igh tness
Work ing l i fe Hand ling a shore Beach ing Propu lsion
An ava l a rch i tec t s hou ld p erhaps c on f ine h i mse lf main ly t o t he l ast t hree q ues t ions . A l l t he i ssues r a ised b y t he m a re h is p rofessiona l c oncern a s t hey a pp ly t o modern s h ips a nd b oa ts .
Why n o t t o a ncien t b oa ts t oo?
B u t t o
a void a n2chron is ms h e n a tura l ly n eeds h e lp f rom a rchaeo log is ts p ar t icu lar ly i n u nders tanding c on te mporary s oc ie ty a nd d ec id ing wha t ma ter ia ls a nd t oo ls may b e a ssumed t o b e a va i lab le f or mak ing t he o r ig ina l . E qua l ly , t he a rchaeo log ist may n eed a l i t t le h e lp fr om t he n ava l a rch i tec t i n s e t t l ing , o r a t l eas t p u t t ing s o me l im i ts o f v ar ia t ion u pon a b oa t 's f unda men ta l f ea tures. Ques t ions may o ccur t o o ne t ha t b ene f i t t he o ther . L oad , s treng th , wa ter t igh tness , s tab i l i ty , p ropu lsion p ower , s peed , r ange a nd s eawor th iness a re a l l c lose ly c onnec ted f ac tors i n a l mos t a ny d es ign o f b oa t . T hey a re p erhaps i t s n ine v i ta l a t tr ibu tes , a nd a re d e ter m ined s o met imes q u i te s ensi t ively , b y t he b oa t 's ma in p ropor t ions , f orm , s can t l ing a nd ma ter ia l ( i nc lud ing f asten ings ) .
V ery o f ten ab oa t f ind c onsists o n ly o f t he
b o t to m o f t he h u l l , a nd o ne , i fn o t b o th e nds may b e missing t oo . T he r ec onstruc tor i s t hen f aced w i th more u nknowns t han e qua t ions ; h e t here fore f aces a p rob le m wh ich , s tr ic t ly s peak ing , i s i nde ter m ina te . One p roposi t ion im med ia te ly f o l lows i n v ir tua l ly a l l s uch c ases : n o o ne r econstruc t ion c an b e p roved t o b e u n ique ly c orrec t , t o t he e xc lusion o f a l l o thers. G enera l ly t here fore , ar econs truc t ion c an o n ly b e more o r l ess l i ke ly - o ne c an s o met imes d o n o more t han a im t o work o u t s o me o f t he more l i ke ly o nes . And t ha t l eads t o a no ther p roposi tion a lready a dvanced i n t he p rev ious p aper : t ha t more t han o ne h ypothe tica l r econs truc t ion o f ab oa t s hou ld b e d eve loped i fn ecessary t o c over p ossibi l i t ies wh ich may b e b o th v ery d i f feren t a nd e qua l ly v a l id .
I nves t iga tors s hou ld t ry t o a void c ha mpion ing a ny o ne u n t i l a l l o thers
h ave t o b e r e jec ted .
May It ake a n e xa mp le? 2 16
F ig . 1 6.1
A mode l o f t he r e ma ins o f F err iby b oa t I .
N at iona l Mar it i me
Museu m.
F ig . 1 6.2
Ah ypothet ica l r econstruc t ion o f aF err iby b oa t -m in i mum s o lu t ion w ith t wo s ide s trakes. N at iona l Mar it i me Museum.
The Bronze Age b oa ts f ound n ear ly 4 0 y ears a go b y Mr . E .V . Wr igh t a t N or th F err iby o n t he R iver H u mber i n B r i ta in p resen t r econs truc tors w i th many p uzzles .
T he r e ma ins d a te f ro m t he 2 nd Mi l le i :m . 1m B .C . a nd a re among
t he o ldest p lank b u i l t b oa ts o f wh ich a ny we l l p reserved r e mains h ave b een f ound .
They d e f ine n ear ly t he whole e x ten t o f t he ma in p ieces f or m ing t he
b o t to m a nd a b i t o f o ne e nd o f o ne l ower s ide s trake b u t l i t t le e lse .
F ig. 1 6.1
s hows a mode l made o f t he r e ma ins o f t he f irs t o f t hese b oa ts t o b e f ound . Though b u i l t , t o t he e x ten t s hown b y t he r e ma ins , w i th mass ive p ieces o f h ewn o ak , s ewn t oge ther w i th y ew s t i tches , t he 1 5 me tre l ong b oa t i s o f s lender f or m , o f l eng th a bou t 8t imes t he l i ke ly max i mum b read th .
T he h e igh t
o f t he s ides a nd h ow much t hey f lared o u t , i n o ther words t he l oaded wa terl ine b read th , a re s uggested b u t n o t d e f ined b y t he r e ma ins .
R ough s tab i l i ty
a nd s treng th c a lcu la t ions t aken t oge ther wou ld l ead a n ava l a rch i tec t t o p onder av ar ie ty o f f or ms f or t he c o mp le te b oa t .
S o me c ou ld n o d oub t b e r e jec ted
o n a rchaeo log ica l a rgue men ts , b u t c onverse ly o thers m igh t n o t i n t he f irst p lace h ave o ccurred t o a n a rchaeo log is t . T o i l lustra te , b u t n o t t o p rove , t he n eed i n many c ases f or p lura l r econs trüc t ions Io f fer t hree o u t o f many o ther p ossib les , o f t he N or th F err iby B oa ts . The f irs t ( F ig . 1 6.2 ) i s a n e f for t t o d es ign a b oat w ith t he l eas t mater ia l i n i t , t hat i s a dd it iona l t o what was a ctua l ly f ound i n t he r e ma ins , a nd n ecessary t o f or m a workab le v esse l w i th a u se fu l p urpose . S uch a b oa t wou ld b e s u f f ic ien t ' Ib e l ieve t o f erry l oads o f a bou t 3 4 t onnes o r s ay 1 0 p eop le a nd 8p add lers a cross a r iver l i ke t he Humber , Io r 2k i lo me tres w ide , w i th a dequa te s ta b i l i ty , j us t e nough f reeboard a nd w i thou t t oo g rea t ar a te o f l eakage t hrough s tra in ing . T here i s c onsiderab le f orce i n n o t s traying f ro m a r a ther p arsimon ious P r inc ip le o f S u f f ic iency i n r econs truc t ing u t i l i tar ian o b jec ts , wha tever t he ir a ge .
I ti s t rue t ha t i n war e qu ip men t a nd v esse ls f or whose t ota l p urpose
v isua l d isp lay may b e a s i mpor tan t a s t he ir p r i mary f unc t ion , d ecora t ion o r p ure ly s ty l ist ic f eatures h ave o f ten e x tended b eyond r e la t ive ly m inor a dd it ions o f f in ia ls , f ash ion p ieces , o r c arv ing . Bu t s uch v esse ls , t hough p rest ig ious , h ave u sua l ly b een r ar i t ies i n t he ir own t i mes r e la t ive t o t he mass o f workad ay c ra f t , s o a ny r econs truc t ion whose ma in f or m h as h ad t o b e a l tered f una men ta l ly t o i nc lude s ubstan t ia l f ea tures o f n o u t i l i tar ian p urpose s hou ld a t trac t s o me d oub ts . Is uggest t ha t i ti s t he d u l l t ru th t ha t o rdinary , u se fu l b oa ts h ave g enera l ly b een d esigned , o r r a ther e vo lved , s o t ha t , g iven t he t echno logy o f t he ir t ime , t hey c ou ld b e b u i l t a s c heap ly a s t heir r equ ired a nd a ccep tab le p er for mance a l lowed . Av ery s ubstan t ia l f ea ture o f t he N or th F err iby b oa ts i s t he ir l eng th a nd s lender f or m . Ex tra l eng th c a l ls f or g rea ter l ong i tudina l s treng th t o a vo id work ing a nd l eakage a t s ea ms.
N arrow b eam g rea t ly r educes s tab i l i ty a nd
l oad c arry ing c apac i ty . H owever l eng th a nd s lender f or m d o make f or s peed , b esides p rov id ing s pace f or more p add lers o r o ars men . T hese b oa ts c ou ld p robab ly b e d r iven b y 8p add lers f a ir ly e asi ly a t a bou t 4k no ts f or a mi le o r s o , a nd a t 5k no ts w i th s o me e f for t . An ava l a rch i tec t must a sk s o me q ues t ions a bou t t he n eed f or s peed b ecause o ne way o r a no ther , s peed i s e xpensive . k no ts o r s o?
Was i tn eeded t o b reas t t he Hu mber t ide s trea m o f 4
Wha t f erry t ra f f ic i n t hose d ays c ou ld h ave made t he l abour o f
b u i lding a nd ma in ta in ing a l ong f as t b oa t wor thwh i le? 2 18
C ou ld a f erry h ave
l anded a nd embarked p assengers e xcep t n ear t he t op o f t he t i de a nyway? T he r easons f or t he l eng th a nd s lenderness o f t he N or th F err iby b oa ts s hou ld b e s ough t i n s uch q uest ions . R easons s hou ld b e kund f or f ea tures s o f undamen ta l t o i t s who le d esign . I n i gnorance o f s uch r easons t he r econstruc tor mus t a ccep t t ha t h e h as n o t t rave l led v ery f ar t owards s eeing t he b oa t f ro m t he b u i lders ' a nd owners ' p oin t o f v iew a nd must meanwh i le k eep a n o pen mind a bou t more d e ta i led s upposi t ions. T he s econd r econstruc t ion i l lustra t ion ( F ig . 1 6.3 ) r epresen ts a more amb i t ious a nd h igher q ua l i ty c ra f t whose ma ter ia ls a nd d e ta i led d esign k eep c lose ly t o t he s ty le o f t he a c tua l N or th F err iby r e mains . I tc ou ld c arry a l arger l oad , a bou t 4t onnes , p rov ided t ha t t he l oad was k ep t p re t ty l ow . I ti s t rue t ha t ad eep b oa t c ou ld c arry a g rea ter l oad w i thou t b e ing s wamped , b u t , b eing r a ther n arrow f or h er l eng th , s he w ou ld b eco me u ns tab le u n less t he a dded l oad were k ep t r e markab ly l ow . A t t he l im i t i t wou ld h ave t o b eco me b a l las t o n t he b o t to m . Un less q u i te e x traord inar i ly f l ar ing s ides c ou ld h ave b een b u i l t t o w iden t he wa terp lane a s s he was l oaded , t he b oa t 's l eng th t o b ea m r a t io o f a bou t 8g ives h er , i fa t a l l d eep , a l l t he v ices o f t he s o c a l led " Cof f in S h ips" o f t ha t u n for tuna te p er iod i nt he l ast c en tury when t onnage a nd t heref ore h arbour d ues were d ecided b y af or mu la wh ich p ena l ised s h ips w i th h ea l thy b ea ms. I n r econs truc ting b oa t r e ma ins o ne mus t b e wary o f p ropor t ions n a tura l i n a n a ge o f l uxur iously s trong ma ter ia ls a nd f asten ings . One may b e f orge t t ing f or i nstance , t o t ake l eakage i n to a ccoun t . S tra ins i ncrease w i th l oad a nd we igh t , s o t he s econd i l lus tra ted r econstruc t ion may b e a sk ing a l o t o f i t s moss c au lk ing t o w i ths tand b e ing r ubbed a s t he j oin ts " work" u nder l oad . We c an e as i ly f orge t , b ecause i ti s ad u l l s ub jec t , t he p as t s erv i tude o f s a i lors t o b a l ing a nd , l a ter , p ump ing . T he s ea ms o f t he N or th F err iby b oa ts were mos t i ngen iously c on tr ived a nd c au lked , b u t w i thou t p rac t ica l e xper ience o f t he m , t heir wa ter t igh tness s hou ld n o t l i gh t ly b e o verest i ma ted p ar t icu lar ly a s t heir h u l ls were s o l ong a nd n arrow .
B i lge wa ter d oes more t han we t t he f ee t
o f p assengers a nd c rew . I n f l a t b o t to med b oa ts i tc an h ave a p rofound e f fect o n t he c ra f t 's b ehav iour p ar t icu lar ly a s r egards s tab i l i ty . L eakage i ncreases w i th d raugh t a nd c ou ld a lso l im i t t he d raugh t t o wh ich i t wou ld b e s ensible t o l oad a b oa t . I ndeed c hron ic p resence o f b i lge wa ter c ou ld b e a dvanced a s r eason f or t he n eed i n t he N or th F err iby b oa ts f or a t h ick f l oor o f wood s taves a nd t w igs t o r educe t he e f fec t o f f ree s ur face i n r educing s tabi l i ty : s uch a f l oor wou ld a lso p ro tec t t he s ea m s t i tches f ro m d a mage b y k ick ing o r s l ipping f ee t o r c argo. Bu t o ne n eeds f i rst t o f ind o u t h ow b ad ly t he b oa ts l eaked . A r ep l ica i s c a l led f or t o p rov ide a c onv inc ing a ssess men t . Iwou ld j udge t ha t N o . 2i s q u i te a s f ar a s t ha t l i ne o f r econs truc t ive t hough t c ou ld p oss ib ly b e t aken . T here a re c er ta in ly many p ossib le h ypo theses a bou t t he d e ta i led c ons truc t ion o f t he e nds o f t h is k ind o f h u l l . A ny n eed t o b end wood o f t he t h ickn ess u sed must b e s e t a side : o n t he o ther h and i t wou ld t ake l i t t le i fa ny l onger t o h ack a c urved s lab o f w ood o u t o f h a l f at ree t runk a s af la t o ne , b u t s uch h eavy ma ter ia l a bove wa ter wou ld b e al i ab i l i ty t o t he d esign i fi t s a dd i t iona l s treng th a nd s o l id i ty wou ld b e u nnecessary . The b oa t i n F ig . 3 wou ld we igh a bou t 3t ons : h au l ing i to u t o f t he wa ter f or r epa irs c ou ld h ave p resen ted s o me p rob le ms .
2 19
A f te rE Y .W ri 9 h t
F ig . 1 6.3
F ig . 1 6.4
Ano ther p oss ib le r econs truc t ion - w ith t hree s trakes a nd c losed e nds. N a t iona l Mar i t i me Museu m.
At h ird r econstruct ion - t wo t imber s trakes w ith a h ide s heers trake a nd a h ogg ing t russ.
Na t iona l Mar it i me Museum.
T he p oin t l eads t o my t h ird e xa mp le ( F ig . 1 6.4 ) wh ich i s o ne o f av ar iety o f d es igns t ha t o ne c ou ld b e l ed t o c on te mpla te a s p oss ib le r econstruc t ions i f
,
o ther s or ts o f c onstruc t ion c ou ld b e a dm i t ted t o h ave f or med a ny o r , e ven a l l , o f t he b oa t b eyond wha t i sf i rm ly d e f ined o r i mp l ied b y t he r e mains . H ere I h ave f o l lowed t he r a ther o bv ious c ourse o f c o mb in ing t he v ery h eavy o ak p ieces f or m ing t he l ower s he l l w i th a much l i gh ter s k in c ons truc t ion f or t he u pper p ar ts a nd p rov id ing a h ogg ing t russ t o p res tress t he h u l l p er manen t ly i n s ag , s o t ha t t he j oin ts w i l l n o t s u f fer r eversing f orces i n s erv ice . n o t t here fore b e s o p rone t o l eak .
They w i l l
S k in b oa ts h ad p resumeably d eve loped i n to
a n e stab l ished a nd w idespead means o f n av iga t ion r ound t he c oas t o f N or th Wes t E urope i n t he c ourse o f N eo li th ic t imes . S k in b oa ts h owever c ou ld n ever h ave b een v ery l ong l i ved , e spec ia l ly when u sed a s af erry , n ecessar i ly t ak ing t he g round i n at i da l r iver a t t he e nd o f e very c rossing . Wha t more u se fu l d eve lop men t t o o verco me t ha t s ho r tco m i ng , t han t o p rov ide s uch a g eograph ica l ly i mportan t f erry n o t o n ly w i th a h ard b o t to m j ust a s s oon a s i tb ecame p ossib le t o h ew wood o n t he s ca le r equ ired t o d o s o b u t a lso t he s treng th n eeded t o e na b le a s lender f or m t o b e p ossib le a nd h ence g rea ter s peed t o b e a ch ieved? I ta ppears t ha t t he a dze marks o n t he N or th F err iby b oa ts a re o f t he max i mum s ize p oss ib le w i th t he a va i lable t oo ls . T hose b oa ts c ou ld t here fore h ave b een , a s we s ay t oday , a t t he f ore fron t o f t echno logy -t he C oncordes o f t he ir t ime i np ropor t ion t o G ross T r iba l P roduc t t hey c ou ld h ave b een a s e xpens ive b u t a rguab ly more u se fu l. T he i ngenu i ty a nd s k i l l o f t he Humberside b oa t b u i lders ( de monstra ted b y t he way t hey j o ined t he o ak s trakes t oge ther ) wou ld s ure ly h ave b een q u i te a dequa te t o s o lve t he p rob le m o f mak ing s u f f icien t ly wa tert igh t j o in ts b e tween t he wooden a nd t he f lex ib le u nstressed s k in p ar ts o f a c o mposi te b oa t . I ti s n o t d i f f icu l t t o c once ive d esigns i n wh ich n o p ar t o f t ha t j oin t i sb e low t he l oaded wa ter line b u t , b ecause e ven t he c lever s ea ms b e tween t he wooden s trakes wou ld h ave b een b y n o means wa ter t igh t a f ter t he s tra ins o f s erv ice , i m mersion o f s o me p ar t o f t he s k in c overed r eg ion c ou ld we l l h ave b een a ccep tab le . T he t hree r econstruc t ions Ih ave i l lustra ted s tand f or a l arge n umber o f r e la ted p rac t ica l p ossibi l i t ies w i th in t he c on f ines o f p rac t ica l n ava l a rch it ec tura l c oncep ts . I ti s n a tura l t o wan t t o r educe t ha t n umber i fp oss ib le t o o ne -t he s ing le a u thor i ta t ive v ersion a s i t were a nd much e f for t i n a rchaeo log ica l a rgumen t s ee ms o n o ccasion t o b e e xpended t o t ha t e nd i n f ie lds b esides t ha t o f b oa ts . I n t he mar i t i me f i r 2 ld t here i s t he f amous a nd we l ln igh p erenn ia l c ase o f t he t r ire me , wh ich o n ly r ecen t ly e rup ted i n to T he T i mes n ewspaper . The e nsu ing c orrespondence wou ld n ot h ave b een v ery c onc lusive h ad n o t s o me f ac ts a bou t p ower , s peed a nd r esistance o f s h ips b een b rough t t o b ear u pon a v ar ie ty o f s uggest ions s o me o f wh ich h ad l acked t he s uppor t o f p hysica l l aws o r e ng ineer ing e xper t ise . T ha t t he s er ious a rchaeo log ica l s tudy o f t he b oa t i s ar e la t ive ly r ecen t d eve lop men t may , Is ugges t , b e d ue f irst t o t he g enera l ly s ubordina te p lace o f mar i t i me a f fa irs i n h istory : t he Wars b e tween G reece a nd P ersia , t he e xp lo i ta t ion o f t he N ew Wor ld b y S pa in , a nd t he p er iod o f B r i t ish s ea p ower a re s o me o f t he e xcep t ions t ha t p rove t he r u le . S econd ly , s h ips a nd b oats a re t echn ica l ly p erhaps r a ther t r ick ier t han t he g enera l r un o f a rchae log ica l r e ma ins l i ke p ots , o rna men ts a nd b u i ld ings a nd t he s cho lar s tudy ing h igh ma t ters o f d ynas t ies a nd t he e bb a nd f l ow o f p eop les a nd c u l tures h as n ot b een
2 21
.a b le t o g lean much a bou t t he t hough ts a nd t echn iques o f t he r e la t ive ly r ude a nd u n le t tered mechan ics , a rch i tec ts o r e ng ineers who c on tr ived t he wherew i tha l o f c iv i l ised l i fe , t rave l , t rade a nd war . N e i ther h ave h istor ians u su a l ly b een e ng ineers , n or e ng ineers h is tor ians , s o Is uggest t ha t s ound s tudy o f h istor ica l s h ips a nd b oa ts mus t i nc lude c onsidera t ion o f t he n ava l a rch i tect ura l f easibi l i ty o f r econstruc t ions w i th a s much r igour a s p ure ly a rchaeo log ica l c ons idera t ions s uch a s s tra t igraphy , c on tex t , o r ig ins a nd a f f in i t ies . S h ips a nd b oa ts h ave e volved b y ac on t inu i ty o f e xper ience s o t ha t , a s i n t he wor ld o f l i v ing o rgan is ms , o n ly a ccep tab ly s uccessfu l d esigns h ave mu l t ip l ied t o f orm t he b oa t p opu la t ion o f t he ir t ime . S o i ti s s ta t is t ica l ly l ike ly t ha t r e ma ins o f b oa ts t ha t a re d iscovered n ow a re o f s uccessfu l d esigns. Excep t ions t o t ha t p roposi t ion , wh ich may b e t hough t t o p rove t he r u le , a re c ases where t he v ery u nsoundness o f ac ra f t may h ave c aused i tt o b e a band oned o r l ost i n s uch a way a s t o r esu l t i n i t s s a fe p reserva t ion . T he Wasa i s as pec tacu lar e xa mp le . A par t h owever f ro m t hose p ecu l iar c ases , wh ich must s ure ly b e a sma l l minor i ty , s ound ly worked o u t r econs truc t ions o f r e ma ins wou ld n ow b e f ound t o b e a dequa te s truc tura l ly , mechan ica l ly , a s r egards s tab il i ty a nd f lu id d yna m ics , a nd i n e nergy c onversion i ft ha t were s ign i f ican t ly i nvo lved i n t he ir o pera t ion .
S uch n ava l a rch i tec tura l c onsidera-
t ions c an e l im ina te a s we l l a s c rea te h ypo theses , r e f in ing a nd c o mp le ting t he s e t o f p ossib le r econs truc t ions o f a ny o ne b oa t wh ich s hou ld a l l b e r egarded a s v a l id . T o r educe p ossib le r econs truc t ions t o o ne p re ma ture ly i s , Is ugges t , ag rea t mis take . Ih ave s a id t ha t , i n t he p ast , s h ips a nd b oa ts e vo lved . T he n ava l a rch i tec t n ow h as s o me s c ien t i f ic me thods t o h e lp h is c rea t ive e ndeavours. N ever thel ess f or s h ip 's s truc ture a nd s tab i l i ty o n ly r e la t ive ly r ecen t ly h ave me thods o f t heore t ica l a ssess men tb een d eve loped . N a tura l ly t hose me thods h ave c oncen tra ted o n t echn ica l ly , e cono m ica l ly a nd mi l i tar i ly i n teres ting c on te mp orary s h ip d esigns , r a ther t han t he a ppra isa l o f s ay B ronze Age b oa ts , o r t r ire mes , b u t s uch a s t hey a re , u se fu l n ava l a rch itectura l me thods o f a na lysis o f s treng th , s tab i l i ty , s peed , p ower a nd s eakeeping a re a va i lab le t o h e lp i n mak ing r econs truc t ions . Imay h ave o ver emphas ised t he n ove l ty o f n umer ica l me thods f or t he a ssess men t o f s tab i l i ty : f or s h ips t hese h ave b een a va i lab le f or t he s ta t ica l c onsidera t ion o f s tab i l i ty f or we l l o ver a c en tury n ow , b u t t heor t ica l u nders tand ing o f d yna m ic b ehav iour i n waves i s s t i l l d eve loping a c t ive ly a nd f or b oa ts d yna m ic b ehav iour i s more i mpor tan t r e la t ive t o s ta t ic s tab i l i ty t han f or l arger s h ips. S truc tura l a na lysis o f s he l ls , wh ich t o a s truc tures man i s wha t s h ips a re , h as d eve loped i n d irec t ions most a pp l icable t o me ta l we lded s h ips : n o s yste ma t ic s tudy o f t he b ehav iour o f s he l ls made o f wood whose s erv iceab le s treng th i s main ly d e ter m ined b y r e la t ive ly weak a nd c rushab le f asten ings b y s t i tches o r s kewers ( or b y t he c la mp ing a c t ion o f r ive ts , b o l ts o r s p ikes ) h as t omy k now ledge y e t b een c arr ied o u t t o h e lp t he a rchaeo log ists. I n a ny h ypo the t ica l r econstruc t ion a n ava l a rch i tec t i sb ound t o a sk q ues t ions a bou t s treng th , p ar t icu lar ly t he s treng th o f j oin ts a nd wha t wou ld h ave b een t heir l i ke ly l eakage wh ich must h ave b een a ccep tab le . t ha t i s ac rucia l q uest ion n o t a lways e asy t o a nswer .
I n e very r econs truc tion
S o me l i ke ly max i mu m s erv ice l oadings o n t he b oa t c an u sua l ly b e p os tul a ted , i ndeed t ha t must b e d one i far econs truc t ion i s t o make a ny e ng ineer ing 2 22
s ense.
C orrespond ing f orces i n a t l eas t s ome me mbers o f t he h u l l , a nd wh ich
w ou ld h ave t o b e t ransm it ted b y a f fec ted j o in ts c an u sua l ly b e c a lcu la ted , e ven i fo n ly a pprox i ma te ly . I ft he s treng th o f t he j o in t o r , more t o t he p o in t , t he r epea ted l oad t ha t t he j o in t c an b ear wh i le r e ma in ing wa ter t igh t i s k nown a nd i ft ha t s treng th ma tches t he c a lcu la ted l oad , t he a ssu mp t ions u nder ly ing t he p ostu la ted l oad o n t he h u l l a re much s uppor ted ( bu t b y n o means p roved ). I f t hey d o n o t ma tch , t hen t hose a ssump t ions a re a l mos t c er ta in ly d isproved b y t ha t t es t a lone - a nd s ure ly t he c orrespond ing h ypo thet ica l r econs truc t ion mus t t hen b e a bandoned f or s uch a b oa t w ou ld b e s carce ly s a t isfac tory ; s he w ou ld s tra in , l eak , o r e ven s p l it o pen s o mewhere u nder h eavy l oad ing i n s erv ice. I ft he p hys ica l b ehav iour o f t he j o in ts i n ab oa t f i nd , f or wh ich e s t i ma tes o f s erv ice l oads c an b e made , i s n o t k nown , t hen Is ugges t t ha t o ne o f t he f i rs t t h ings o ne s hou ld d o b y w ay o f f ounda t ion w ork f or h ypo the t ica l r econs truc t ions i s t o make s ome t es t s pec imens o f t he mos t l i ke ly v ers ions o f s uch j o in ts a nd t o t est t he m t o d iscover t he ir q ua l it ies a s j o in ts b etween b oa t h u l l me mbers. T he mos t i mpor tan t q ua l i ty o f ah u l l j o in t i s n ot s o much i t s s treng th t o c arry t he r equ ired l oad w ithou t c om ing a par t , b u t i t s s treng th u nder r epea ted l oad ing wh ile r ema in ing w a ter t igh t . T he v ery w ord " wa ter t igh t" i s most a p t , f or n o l oose j o in t , h owever s trong i t may b e , w i l l k eep w a ter o u t .
T ha t i s p a ten t ly
o bv ious i n t he c ase o f wood j o in ts w hose w a ter t igh tness d epends u pon t he c lose ma t ing a nd c lamp ing t oge ther o f t he ir c omponen t p ieces. Where n e ither f i t n or c lamp ing c an b e a ch ieved , b oa tbu i lders a s a t N or th F err iby a nd i ndeed b u i lders e verywhere o f s ewn p lank b u i l t b oa ts a s w e l l a s c arve l b oa ts h ave h ad t o r e ly o n s tu f f ing t he ir j o in ts a nd p ou l t ic ing t hem w ith ma ter ia ls t o make wha t i s e ssen t ia l ly a l i gh t ly p acked l abyr in th o f f i bres t o r educe t he f l ow o f wa ter t hrough t he s eam o r j o in t . I fv ery t i gh t ly p acked , g reasy f i bres c an b y s ur face t ens ion a ctua l ly p reven t w ater f rom p ene tra t ing t h e j o in t , b u t mos t b u i lders a nd s eamen h ave h ad t o b e c on ten t i n p rac t ice w ith a pprec iab le s eepage . N e ither af i t ted n or a c au lked j o in t r ema ins t i gh t f or l ong i fi t "works" u nder s erv ice l oads.
I t mus t n o t o pen o r s l ip u nder t he l oads a pp l ied i n s erv ice , wh ich
t here fore c an i n p rac t ice b e o n ly a f rac t ion o f t he a c tua l f a i lure l oad o f t he j o in t . Un t i l t he a rr iva l i n o ur own t imes o f t ru ly wa terproo f g lues , i t was n ear ly a lways t he r equ ired v o lume o f w ood o r r equ ired b ear ing a reas i n a j o in t t ha t d e term ined t he s can t l ings o f t he me mbers , t he s ty le o fj o in ts a nd t here fore t he s ty le o f t he w ho le s truc ture. T he s treng th o f w ood i t se lf h as v ir tua l ly n ever b een f u l ly e xp lo i ted i n s truc tures - a t t he c ruc ia l p ar ts i n t he j o in ts h igh c rush ing s tresses a re c oncen tra ted o ver q u ite sma l l a reas wh i le t he me mbers j o ined a re y e t c arry ing l ow s tress. I nj o in ing o ne p iece o f w ooden h u l l t o a no ther w i th s t itches , t reena i ls , r ivets a nd t he r es t , t he p rob lem h as a lways b een t o o bta in s u f f ic ien t c la mp ing f orce o rb ear ing a rea t o c arry s erv ice l oads b y f r ic t ion w ithou t s l ipp ing , a nd y e t a vo id t oo mass ive s can t l ings t o h o ld t he s ize a nd n umber o f f as ten ings n eeded . I ti s n o t s urpr is ing t ha tu nder s uch c ons tra in ts t he n umber o f t ypes o fj o in ts emp loyed b y b oa t b u i lders t he w or ld o ver a nd d own t he y ears h as n o t b een s o v ery g rea t . B efore l eav ing j o in ts t he a n iso trop ic n a ture o f w ood mus t b e men t ioned b ecause b oa t b u i lders h ave f or a l ong t ime e xp lo ited t he f ac t t ha t w ood s we l ls i n w a ter a cross t he g ra in more t han a long i t . Tha t p roper ty mus t b e r esponsi b le f or a l arge p ar t o f t he t ens ion i n f as teners a nd h ence c lamp ing f orce i n 2 23
/ e
W
F ig . 1 6.5
Transverse s tab i l ity d iagra m : G
c en tre o f g rav ity o f s h ip
B
c en tro id o f t he v o lu me o f w a ter d isp laced b y t he s h ip
W
d isp lace men t o f t he s h ip
M
metacen tre
( cen tre o f b uoyancy )
GM metacen tr ic h e igh t - a measure o f i n it ia l s tab i l ity Na t iona l Mar it i me Museu m.
F ig . 1 6.6
Con jectura l r ow ing a rrange men ts f or a t r ire me. Mar it i me Museu m.
N a t iona l
a riveted lap joint between two pieces of wood, as for instance in clinker construction. Similarly it enables treenails, especially if split and wedged, to develop a clamping force which adds usefully tu the load that can be carried by friction, without slippage, and therefore leakage. It is as difficult to stop a naval architect from talking about stability as a gardener about manure. As important as making tolerably watertight joints is forming a ship or boat to float the right way up and sufficiently resist all those forces tending to push her over. A racing eight is a balancing act, so is a battleship due to its load of deck armour and guns and so was the Wasa, but she fell over. Old shipwrights stuck to rules of proportion and very wise they were to do so until at least statical stability was understood mathematically. The need for those rules is sufficiently explained by 3 factors: First that in any novel design one may assume that the centre of gravity of the ship, G, (Fig. 16.5) will be a bit higher than you think it is going to be. Second that its weight will be greater than you think. Third that the height of the metacentre (M) (which must be above the centre of gravity and by more than some amount if the ship is to be sufficiently stable for service) above the centroid (B) of the volume (V) of the water displaced by the ship is a. proportional to the cube of the beam, and b. inversely proportional to the displacement of the ship (V). To naval architects,
I BM=- a V
3
Beam Displacement
(I is the second moment of inertia of the water plane about its fore and aft axis of symmetry.) That formula explains why beam is so powerful a factor in stability, why a deep ship (relative to beam) is tender, and why it is quite usual for a ship to be less stable when loaded than empty even if in being loaded her centre of gravity does fall: to maintain stability it has to fall enough to cope with the reduction in BM, due to increase in displacement, even though the centre of buoyancy rises relative to the keel as the ship's draught increases. It follows that a little increase in beam, say 5%, could well convert a crank ship into a good one because BM could increase by about 15% which, depending upon how desperately close G was to M originally, could multiply GM, the measure of stability, manyfold. The stability of any unfamiliar ship or craft can never be assumed to be satisfactory, so there can be few reconstructions that can be assumed to be sound without some check on stability. Without possession of her builders' experience and rules of proportion, no reconstructor can be sure that his hypothetical creation would be stable, except by calculation. But no matter how well a reconstruction is worked out by theory and ap plied technical knowledge, no wise naval architect would be too confident about 225
i ts p er formance a nd p rac t ica l b ehav iour , e ven o f a sma l l b oa t , u n less a r ep l ica o f i th ad a ctua l ly b een made a nd t es ted a t s ea.
T he Na t iona l Mar it i me Museu m
h as p ioneered t h is f orm o f e xper i men ta l a rchaeo logy i n i t s p rac t ica l r esearch w ith a r ep l ica o f t he G okstad F aer ing .
Much h as a lso b een l earned , a s c ou ld
h ave c o me t o l igh t i nn o o ther way , f ro m r ep l icas o f s h ips s uch a s May f lower , Go lden H ind a nd N on S uch , e ven t hough t he d es ign o f s uch r e la t ive ly r ecen t v esse ls i s f a ir ly we l l e stab l ished .
I deas a bou t G reek t r ire mes w ou ld h ave b een
s or ted o u t b et ter i fe ven o n ly o ne o f t he s evera l p oss ib le r econs truc t ions wh ich h ave b een a dvanced h ad a ctua l ly b een r econs tructed :
i ndeed u n t il t ha t i s
d one I s uspect t ha t l i tt le f ur ther r ea l p rogress c an b e made o n t he s ub ject o f t r ire mes. Prel im inary p ract ica l t r ia ls o f r ow ing a rrange men ts s a id t o h ave b een made s o me t ime a go b y Kopecky ( F ig . 1 6.6 ) a nd A lexanderson n eed t o b e e x tended t o t he who le s h ip t o p u t an u mber o f s he lved b u t e ssen t ia l q ua l it ies t o t he q ues t ion.
A f ew o f t hose q uest ions a ddress t he n ava l a rch itect 's b read
a nd b u t ter s ub jec ts o f : S tab i l ity
: Wha t wea ther c ou ld t r ire mes s tand a nd h ow w ere t hey worked i n h eavy s eas?
We igh t ( abou t 6 0 t ons )
: Were t hey d rawn u p o n b eaches?
S treng th
•D id t hey n eed a n e nc irc l ing r ope u nder t ens ion t o p reven t h ogg ing f a ilure?
A l l t hree a f fec t t he ir n ava l o perat ion a nd t here fore t he f eas ib le l im its o f s ea p ower t ha t c ou ld b e e xerc ised b y t he m , t o a n e x ten t t ha t s hou ld b e o f i n terest t o h istor ians o f t he p er iod. I ti s r are ly p rac t ica l t o b u i ld a t rue r ep l ica .
Many ma ter ia ls o nce e as i ly
a va i lab le h ave b eco me s carce e ither i n t he r igh t f or m o r e ven i n a ny f or m. I t i s n ot e asy t o b e s ure o f t he o ld t echn iques b y wh ich ma ter ia ls w ere f ormed p repared o r a sse mb led - a nd l im itat ions o f t echn ique h ave e ver b een a c o mp e l l ing d isc ip l ine t o a rch itects a nd c ra f ts men :
t hey c an d e term ine t he who le
s ty le o f ad es ign i n ways u n i mag inab le u n t il o ne t r ies t o d o i to nesel f -t hat i s i n i tse lf a c o mp lete j us t if ica t ion o f t he v iew , t ha t u n t i l o ne h as made a nd worked a ny a r t ifact ( excep t i tb e o f r ea l ly q u ite e x tre me s i mp l ic ity o r l ack o f n ove l ty , a nd n o b oa t i s e ither o f t hose ), o ne k nows v ery l i t t le a bou t i t . Ta lk ing a nd t heor is ing may b oth b e n ecessary p re l im inary s tages t o u nders tand ing , b u t n o ma t ter h ow p laus ib le o r i n te l lectua l ly a t tract ive t he r esu lts may b e , t hey c an d o n o more t han f orm a s e t o f i deas a bou t ab oa t wh ich may b e wor th t est ing i n aw orkshop , o n t he b each a nd a t s ea.
A f ter t ha t r ea l
e xper ience , a nd g et t ing p erhaps c u t , b ru ised a nd we t , o ne 's u nders tand ing s u f fers a l i tera l s ea c hange.
A n ew p erspec t ive o f p rac t ica l q ues t ions a r ises
a nd o ne c an r eturn t o t hose I s tar ted w ith a rmed w ith k now ledge o f a n a l tog ether d eeper a nd more c onv inc ing k ind wh ich i s u nob ta inab le i n a ny o ther way .
REFERENCES McGra il , S . a nd McKee , E ., 1 974 , Bu i ld ing a nd T r ia ls o f t he r ep l ica o f a n a nc ien t b oa t :
t he G okstad f aer ing .
N .M .M . Monograph No. 1.
Wr igh t , E . V ., 1 976, T he N or th F err iby Boa ts.
2 26
N .M .M . Monograph No. 2 3.
D ISCUSS ION Cor let t
T he Graveney Boa t i s ag ood e xamp le o f u s ing s evera l d isc ip l ines t o t ry a nd g et a r ea l i dea o f wha t ab oa t was b u i l t f or , b ut , a l though n ava l a rch itects , ma the ma t ic ians a nd s o o n , c an h e lp , t hey mus t n o t t respass o n t he f i e ld o f t he a rchaeo lo g ist .
I n t he c ase o f t he G raveney Boa t t he n ava l a rch itec t
c an e s t i ma te v ery c lose ly t he p ower r equ ired t o d r ive h er a t v ar ious s peeds , wha t l im ita t ions o n s peed a pp l ied , wha t t ype o f s tab il ity s he h ad a nd h ence p oss ib ly t he c argo s he w ou ld h ave b een l ike ly t o c arry .
As Mr . Coa tes h as i nd ica-
t ed y ou c an a lso g et a p ret ty g ood i dea o f t he s peed p o ten t ia l o f t he F err iby Boa ts.
T h is i s h e lpfu l i n forma t ion t o g ive t o
t he a rchaeo log ist w ithou t i n a ny way t respass ing o n h is p reserves. A t t he mo men t Iam w ork ing o n t r ire mes i n s o me d ep th , a nd we a re a lready i nvo lved i n s tructura l i nvest iga t ions. A g rea t d ea l i s c om ing t o l igh t w h ich e xp la ins wha t s ome p ecu l iar l ook ing r epresen ta t ions o n v ases , p a in t ings , a nd c o ins , r ea l ly w ere.
T here a re s evera l h ypotheses f or s o me o f t he f ea tures ,
b u t t here c an o n ly b e o ne o r t wo r ea l t echn ica l s o lu t ions a nd i n s o me c ases o n ly o ne. F or e xamp le , t he b ronze r am f i t ted t o t r ire mes i s s hown o n c o ins t o b e n o t p ara l le l t o t he wa terl i ne. T here i s av ery g ood t echn ica l r eason f or t h is : i t mus t p o in t t hrough t he c en tre o f g rav ity , o therw ise when t he t r ir e me r am med a no ther s h ip i tw ou ld b e r ipped o f f b y af orce wh ich c an b e c a lcu la ted , s o meth ing l ike t hree t ons v er t ica l ly a t t he s te m. McGra i l
J ohn Coa tes h as s hown u s t hree v ar ian ts o f t he F err iby b oa t a nd t hey a ppear t o h ave s ign if ican t d i f ferences i n p er formance. Are t here a ny v ar ian t s o lut ions t o t he Graveney b oa t r econst ruct ion wh ich w ou ld h ave s ign if ican t d i f ferences i n p er for ma nce?
It h ink Er ic McKee h as max i mu m a nd m in i mu m
s o lu t ions b u t d o t hey d ifer s ign if ican t ly? McKee
Id on 't t h ink t here w ou ld b e al o t o f d iference i n t he h ydros ta t ic s hape o f e i ther s o lu t ion . ' Id idn 't h ave much c ho ice r ea l ly a s t he b ot to m o f t he b oa t was r ecovered a l mos t u p t o t he wa ter l ine.
T he p er formance o f ab oa t w ith a v ery h igh
t ops ides w ou ld b e v ery d if feren t f ro m o ne w ith n o t ops ides b oth i n as ea when u nder o ars o r when s a i l ing a ga inst t he w ind. T he Ad m ira l ty e xper i men ta l l abora tory a t Has lar r an a p rog ra m me t o s ee h ow s he w ou ld b ehave i n as eaway , a nd t hese f igures s how t ha t s he c orrects h erse lf s o f as t t ha t i n b ad w ea ther s he m igh t b reak h erse lf u p t here wou ld b e s o much r eserve b uoyancy . There i s n o w indward c apab i l ity o n ab oat l ike t ha t , o r v ery l i t t le , s o s tab i l ity i n t he s ense o f h o ld ing t he b oa t u p t o t he w ind , i sn 't a ny th ing l ike a s i mpor tan t a s i tw ou ld b e i n a modern f ore a nd a f t s a i l ing v esse l. T h is s or t o f d a ta i s v ery i n terest ing a f ter y ou h ave d one t he 2 27
r econstruc t ion : i td oes n o t t e l l y ou t he r econstruct ion i s r igh t b ut i td oes t e l l y ou s o me th ing a bou t what y ou h ave c on jured u p . Mc G ra i l
May Ic lar ify t hat? I s t he Graveney Boa t as pec ia l c ase r a ther l ike S ut ton Hoo where t here i s p robab ly o n ly o ne s o lu t ion t o t he p rob le m o f r econs truct ion?
McKee
Ic an g ive y ou s evera l s o lu t ions , b u t t he r equ ire men t a t t ha t t ime was t o p roduce a s o lu t ion f or t he b u i ld ing o f ar ep l ica a nd o bv ious ly t he Museu m w as n o t g o ing t o b u i ld s ix f u l l s ized r ep l icas. Bu t Id on 't t h ink t ha t w ith a ny s o lut ion y ou a re g o ing t o c hange t he u nderwa ter s hape v ery much.
Cor le tt
It h ink t h is i s t rue. I n t he c ase o f t he F err iby Boa ts y ou c ou ld h ave s evera l a pprec iab ly d if feren t h ydrodynam ic s o lut i ons , w ith measurab le d if ference b e tween t he m.
I n t he c ase
o f t he Graveney Boa t t he h ydrodyna m ic s o lu t ion i s u n ique :
i t
i s a bove t he wa ter l ine , t ha t t he p oss ib le d i f ference a ppear t o b e. It h ink a nother v ery u se fu l h e lp t he n ava l a rch itec t c an g ive i s i n c o mpar isons w ith e x ist ing v esse ls.
F or e xamp le ,
y ou c an l earn a g rea t d ea l a bou t a nc ien t Egypt ian v esse ls f rom l ook ing a t t he d es ign a nd c onstruct ion o f modern Bang ladesh c ra f t. T here a re d is t inct s im i lar it ies i n b o th c onst ruc t ion a nd d es ign.
Why?
T he a nswer i s , t hat t hey b oth
o pera te i n s im ilar e nv ironmen ts.
Exam ina t ion o f s ome o f t he
Bang ladesh c raf t It h ink c ou ld a lso h ave a d ist inct b ear ing o n t he Nor th F err iby Boa ts , f or t here a ga in y ou a re d o ing t he s a me t h ing , f erry ing g oods a nd p eop le a cross w ide a nd s o met imes f as t f l ow ing r ivers.
Ih ave s een b oa ts i n Eas t P ak istan
t ha t a re v ery o bv ious l ong d is tance c ous ins o f t he F err iby Boa ts , d is tan t b oth i n t ime a nd g eography . Chr is tensen
I n t he v ar ious s tern r econstruc t ions o f t he Graveney Boa t s hown b y Er ic McKee t here was o ne w ith p lanks n arrow ing v ery much t owards t he s tern p osts a nd y ou h ad p u t s o me n ice l ash ings a round i tt o k eep e very th ing t ogether .
Why n ot t ry t o u se t he
s o lu t ion w e k now f ro m S cand inav ia where many t h in p lanks a re a sse mb led i n to o ne p iece w h ich r uns t o t he s te m , as tepp ed h ood e nd p ick ing u p s evera l p lanks? McKee
T h is s o lu t ion was c ons idered b u t was n o t i nc luded b ecause I d idn 't r eckon t ha t t he l eve l o f s h ipwr igh try i n t he G raveney Boa t was h igh e nough t o a ch ieve t ha t e xce l lence o f w orkmans h ip.
Wr igh t
Can J ohn Coa tes t e l l u s more a bou t t he s or t o f p er formance wh ich we m igh t e xpect f ro m a t wo s trake , m in i mum s o lu t ion F err iby b oa t w ith i t s mass ive ly h eavy s tructure a nd w ith a v ery l ow f reeboard .
2 28
Coa tes
I ft he r e ma ins a s t hey a re k nown w ere p u t i n to t he wa ter w ith n oth ing a dded , t hey wou ld f l oa t w ith t he u pper s ur face o f t he b ot to m s l igh t ly a bove wa ter. S o o ne w ou ld h ave a workab le p la t form i n smooth wa ter wh ich wou ldn 't c arry v ery much . Ib el ieve t here i s g rea t mer it i n a ny r econs truct ion o f a n a nc ien t b oa t f ind i n s eek ing t he m in i mum s o lu t ion wh ich w i l l g ive a n a ccep tab le p er formance. D ef in ing t he a nc ien t s tanda rd o f a ccep tab le p er formance i s d i f f icu l t , b u t t ha t i s why o ne mus t l ook most c arefu l ly a t t he c ircumstances i n wh ich i t was b u i l t , t he l ike ly p urpose i ts erved .
The F err iby b oa ts
w ere f ound o n t he Hu mber , a nd w ere p robab ly u sed t here a s f err ies.
We s hou ld c ons ider whe ther t here migh t h ave b een
ar equ ire men t t o o perate t h is f erry when i t was a b it c hoppy o r when t he t i de was r unn ing h igh , o r whether i tc ou ld wa it u n t i l t he w ind d ropped. I n t he l a t ter c ase g ood f reeboard w ou ld n ot b e r equ ired. o f t h is b oa t :
We s hou ld t hen c ons ider t he l eng th
t ha t must h ave c ost a t re mendous amoun t ;
t he l owes t s ide s trakes were c o lossa l c hunks o f o ak .
T here
mus t h ave b een s o me v ery g ood r eason t o make i ta s l ong a s It h ink i t was - p erhaps t he f erry s erv ice was u rgen t . Perh aps a lso t hey d id wan t t he b oa t t o c ross t he r iver when a f u l l t i de was r unn ing , i n wh ich c ase t he n eed f or h igher s ides t o p rov ide f reeboard b eg ins t hen t o a ppear. Iam s uggest ing t ha t p erhaps w e s hou ld s top a t t wo s trakes e ach s ide. Cor let t
L eng th i s t he mos t e xpens ive d i mens ion i n as h ip , i ti s v ery e xpens ive i n a ny t erms y ou l ike t o n a me, money , man h ours , ma ter ia l .
Id on 't b e l ieve t ha t t he F err iby Boat wou ld h ave
b een b u ilt l ong a nd n arrow i n t hat way u n less t hey w ere i nt erested t o s o me e x ten t i n s peed. T here w ou ld b e p ressures t o o b ta in more r egu lar ity f or t he f erry s erv ice , t o c arry a b it more - f our c ows i nstead o f t hree a nd s o o n .
It h ink o ne
h as g o t t o b e c arefu l o f a pp ly ing t oo r igorous ly t he l east e f for t s o lu t ion , i ti s o ne s o lu t ion b ut Id on 't t h ink i ti s n ecessar ily t he p referred o ne. L ove l l
How d o w e k now t ha t t hese r ather b are f inds a re i n f act b oa ts a t a l l? Cou ld t hey p oss ib ly b e s ome f orm o f v essel o r t ank i n wh ich y ou c an s tow t h ings? Have t here i n f act b een f inds wh ich were f i rst t hough t t o b e b oa ts a nd s ubsequen t ly t urned o ut t o b e s o meth ing e lse?
Wr igh t
T here i s n o d oubt i n my mind t ha t w e h ave e xamp les o f t hree b oa ts a t F err iby . Iwou ld a sk S ean McGra i l who h as s tud ied a l l t he d ugou ts r ecorded i n t h is c oun try a nd many o f t he I r ish o nes a s w e l l , t o t e l l u s wha t p ercen tage o f t he m o n e xam inat i on l ook a s i ft hey a ren 't b oats a t a l l .
McGra il
It h ink t he g rea t b u lk o f t hose a r t ifac ts c a l led d ugou t c anoes a re o bv ious ly b oa ts o f s o me s or t . On t he o ther h and s o me o f t he sma l ler o b jects a re c of f ins , a nd t here a re t roughs f or b rew ing a nd t he l ike.
The c ircu ms tances o f t he f ind , t he
2 29
l eng th a nd t he f ea tures c an o f ten h e lp t o d e term ine whether af ind i s al ogboat o f n ot . am u ncer ta in :
T here a re s o me f inds o f wh ich I
t hese a re t he f rag men tary f inds whose c ir-
c u mstances o f r ecovery a re n o t w e l l r ecorded .
Cap ta in
L ove l l 's r e marks r em ind me t ha t t he Br igg ' ra f t ' was o nce p ub l ic ised a s p oss ib ly a p on toon b r idge, a l though t here w ere o bv ious ly a t te mp ts t o make i t wa ter t igh t .
Is ee s evera l p os-
s ib le r econs truct ions o f t he Br igg ' ra f t ', mos t o f t he m o f t he p un t o r f la t b o t to med b arge t ype. Wilson
May Ic o m men t o n t he s tate men ts a bou t l eng th?
F irst o f a l l
l ong t rees w ere v ery much more c o m mon i n a n t iqu ity .
S ec-
o nd ly when y ou a re c onver t ing a n o ak t ree w ith p r im it ive i ns tru men ts , t he l onger t he p lank t he b e t ter b ecause y ou a re s p l it t ing . Cor let t
Yes , d ugou t c anoes o f c c i -rse a re a n o bv ious e xa mp le , t hey w ere v ery l ong i n r e lat ion t o t he ir b read th a nd d ep th .
Bu t
when y ou s tar t p u t t ing j o in ts i n to k ee l p lanks a s i n t he F err iby b oa ts , It h ink p erhaps y ou a re g e t t ing i n to a s l igh t ly d if feren t f i e ld.
I ti s av ery d if f icu lt t h ing t o d o a nd It h ink y ou w il l
o n ly d o i ti fy ou r ea l ly wan t t he e x tra l eng th. Windsor
S peakers h ave s ta ted t hat t he F err iby b oa ts were f err ies. Bu t i s t h is n o t a nachron ist ic f or t he Bronze Age , b ecause a f erry i s p ar t o f al and r ou te.
Wr igh t
N or th a nd S outh F err iby a re c lose t o t he c ha lk e scarp men t o f t he L inco lnsh ire Yorksh ire Wo lds , o ne o f t he t wo ma jor p reh is tor ic t rackways a long wh ich Nor th/South t rave l i s f a ir ly we l l s ubstan t ia ted.
Al i t t le t o t he west t here i s a no ther e s-
c arpmen t , t he J urass ic e scarp men t , Brough-on-Hu mber t o t he n or th a nd Win tr ingha m t o t he s ou th wh ich b eca me more impor tan t i n Ro mano-Br it ish t imes a s ac ross ing p o in t .
I n
t he M idd le Ages t here w ere f err ies a cross t ha t r ou te a nd t hey a re w el l s ubs tan t ia ted i n Doo msday . Cross ing ma jor water o bstac les must i n a nc ien t t imes h ave b een o ne o f t he ma in p urposes f or w h ich s h ips were b u il t . A t Br igg o n t he R iver Ancho l me y ou h ave a c o mparat ive ly n arrow r iver where s o meth ing l ike a f l a t b otto med p un t wou ld h ave b een a n i dea l f erry p erhaps w ith a r ope a cross a nd y ou h au led i to ver , c a t t le a nd a l l t he r est o f i t .
The F err iby
c ross ing i s af a ir ly s ubstan t ia l o bs tac le , f requen t ly w ith b ad w ea ther where o ne wou ld n eed s o meth ing more e labora te. Coa tes
Wou ld i tn ot b e r igh t t o s ay t ha t t he Hu mber a t t ha t t ime wou ld h ave p resen ted r ea l ly q u ite a l ong o bstac le b ecause u pstrea m t here w ou ld h ave b een a morass f ro m where t he mou th o f t he Tren t n ow i s e x tend ing u p t o t he P enn ines.
T he F err iby c ross-
i ng w ou ld t hus b e a mos t impor tan t r ou te. E l l mers
I n G ermany , France a nd i n P o land , f err ies c ons isted o f d ugo uts t i es t ogether s ide b y s ide , h av ing a p la t for m o n t he m 2 30
mak ing a b road c ra f t wh ich c ou ld c arry , f or i ns tance , wagons , c at t le o r t he l ike. ( D ie Kunde NS24 ( 1973 ) :23-62.) Na ish
One d oes w onder who w ished t o c ross t he Hu mber a t t ha t p o in t a t t hat t ime , n ot o ne p erson b u t q u ite a l o t o f p eop le i n o rder t o k eep t he s erv ice g o ing . Ih ave a lways t hought t hey must h ave g one a cross t he Nor th S ea r a ther t han j ust t he Hu mber .
McGra i l
We s hou ld r e me mber t ha t t he e nv iron men t , t he c l i ma te a nd t he s ea l eve l o f F err iby b oa t t imes w ere n o t n ecessar i ly a s t hey a re t oday.
T here i s much r esearch t o b e d one h ere , b u t
w e mus t c ons ider t hese f actors when we s pecu late a bou t p oss ib le u ses o f t hese b oats.
It h ink i tc an b e s hown w ith f a ir
c er ta in ty , f or e xa mp le, t ha t t here was n o f orma l R iver Ancho l me a t t he t ime o f t he Br igg ' ra f t ', b ut a w ide s ha l low c reek o pen t o t he Hu mber . May Ia sk a bou t Co mmander McKee 's l ast s en tence o n p age 1 o f h is p aper when h e a ppears t o d if feren t ia te b etween r ecord ing a f ind a s ac ata logue o f f ac ts a nd r ecord ing i ti n t he k now ledge t ha t h e i s g o ing t o h ave t o r econs truct .
S hou ld we
n ot h ave t he s a me t horoughness , a nd s hou ld w e n ot a lso make as tr ict d iv is ion b etween o bserva t ion a nd i n terpretat ion? McKee
T he Graveney B oa t h as b een r ecorded t w ice , o nce i n at o ta l ly o b ject ive w ay l arge ly b y p hotograph wh ich w ere t re mendous ly u se fu l i n t he r econstruct ion .
However , t he p hotographer w il l
t ake a p icture o f e very th ing , b ut n o t n ecessar i ly f rom t he a ng le t he r econs tructor wan ts. Now w ith a c er ta in amoun t o f b oa tb u i ld ing e xper ience b eh ind me Ic oncen trated my r ecord ing o n c er ta in t h ings wh ich Ik new wou ld h e lp me t o p ut i tt oge ther a ga in .
F or e xamp le , t he b eve l a ng le o n t he l aps.
T he p ho to-
g raphy h ad r ecorded w ithou t measur ing t he b evel. C o les
T here i s e v idence f or c on t inu ing i fs porad ic c on tact a cross t he N or th S ea i n t he Bronze Age , a nd n ot j us t t he s hor tes t s ea r ou te b u t c lose i n t i ma te r e la t ionsh ips b etween t he Yorksh ire a nd t he L inco lnsh ire c oast d irect t o t he c on t inen t .
P erhaps
b y t reat ing t he F err iby f i nds , wh ich s how many a spects o f Bronze Age s oc ia l o rgan isa t ion , a s p urely i n land v esse ls , w e a re c onstr ict ing o ur v iews o n r econs truct ions. We s hou ld p erhaps l ook more w ide ly a nd s ay c ou ld t hese h ave b een o cean g o ing v esse ls?
I fs o what wou ld t hey c arry , a nd h ow w ou ld
t hey s tand u p t o Nor th S ea c ond it ions?
Based o n t he r e lat ive ly
l i t t le work p ub l ished a bou t Bronze Age s ea l eve ls a nd n a tura l c ond it ions , t he Hu mber wou ld p robab ly b e a s n as ty t hen a s i t i s t oday .
F err iby m igh t n o t h ave b een a t err ib ly a ppropr ia te
p lace f or a f erry t ha t was e xpected t o c ross o nce a n h our o r t hree t imes a d ay o r f ive t imes a w eek .
Cou ld t h is n o t h ave
b een a much more ma jor a f fa ir , t ha t t hese m igh t h ave b een Nor th S ea c ra f t? T h is wou ld n o d oubt a f fect t he r econstruct ions a nd i t wou ld b e v ery i n terest ing t o s ee a mode l o r s o me p roj ec t ion o f wha t s uch c ra f t w ou ld h ave l ooked l i ke i fi n f ac t i t was g o ing t o b e u sed i n t h is way . 2 31
Coa tes
T he F err iby r e ma ins c ou ld b e b u ilt u p i n to a s ea g o ing v ers ion , b ut Is ugges t t ha t i tw ou ld h ave t wo q u ite s er ious d rawbacks. One , i t wou ld h ave i nadequa te s tab i l ity t o c arry a wor thwh i le l oad ;
a nd s econd i t wou ld b e a most e xpens ive a nd l abor ious
t echn ica l s o lut ion t o p rov id ing a s ea g o ing c ra f t.
I f Iw ere
ab oatbu i lder t hen a nd Iwas a sked t o b u i ld a b oat t o c ross t he Nor th S ea , Iw ou ld c er ta in ly b u ild a s k in b oat .
I t wou ld b e a
t en th o f t he c os t , a nd much more e as ily r epa irab le.
The
a dvantage o f t he Nor th F err iby b oat 's h ard b o t to m c ou ld b e s o w e l l s acr if iced f or s uch a g rea t r educt ion i n c ost . Cor let t
Cou ld a b oa t w ith t he p ropor t ions o f t he F err iby b oat b e o ther t han o ar p rope l led?
P erhaps a s quare s a i l i n af o l low ing
w ind? Coates
I t wou ld h ave t o b e av ery p ure f o l low ing w ind .
Farre l l
Co m mander McKee d is m issed t he p oss ib i l ity o f ap re-formed s te m f or t he Graveney b oat s uggested b y Chr istensen o n t he g rounds t ha t i tw ou ld h ave b een a f a ir ly d if icu l t s or t o f c arp en try .
McKee
D id h e c ons ider t he p oss ib le u se o f s tea lers f or t he
p lank e nds? Iwou ld h ave t hough t t hey w ou ld h ave b een f a ir ly s i mp le c arpen try . It h ink i s t he q u ick a nswer t o t ha t .
2 32
1 7.
EXPER I MENTAL ARCHAEOLOGY THEORY AND PR INC IPLES J . M. C o les
S u mmary Exper i men ts w i th a rchaeo log ica l ma ter ia ls h ave b een c onducted f or o ver 1 00 y ears , y et t here h as b een l i t t le a t temp t , u n t i l r ecen t ly , t o c ons ider t he t heory b eh ind e xper i men ts , a nd t he p r inc ip les t ha t mus t g u ide t he w ork . T hree l eve ls o f e xper i men t c an b e d is t ingu ished , d isp lay , p roduct ion a nd f unc t ion , e ach o f w h ich h as i t s o wn r eq u ire men ts. T he v a lue o f r epe t it ion a nd s er iestes t ing c an b e d ocumen ted , b u t t he u se o f s ca le- mode ls a s s ubs t i tutes f or l i fe-s ize e xper i mcn ts i s g enera l ly h azardouG. T ne r e l iab i l ity o f e xper i men ta l r esu lts mus t b e c r i t ica l ly e xam ined , a nd a bso lu te p roo f i s a s u n l ike ly t o b e a ch ieved a s i n o ther a rchaeo log ica l f i e lds. T he v a lue o f t he a pproach , h owever , c anno t b e d ispu ted , b ecause e xper i men ta l w ork f orces t he a rchaeo log ist t o t h ink much more d eep ly t han h i ther to a bou t t he ma ter ia ls , t he t echno log ies a nd t he a c t iv it ies o f p as t h uman s oc ie t ies.
T h is p aper w i l l b e c oncerned more w ith t he p r inc ip les a nd t heor ies o f e xper i men t t han w i th b oa t a rchaeo logy , a l though p ar t icu lar a spec ts o f t he p rob lem o f wooden r econs truc t ion w i l l b e n o ted , i n t he b e l ief t ha t t hey a re r e levan t t o t he s ub jec t o f t he s ympos ium . A l though a n t iquar ians a nd a rchaeo log ists h ave b een aware o f t he e xper i men ta l a pproach f or o ver a c en tury , t here h as b een n o c oncer ted a t temp t t o d ev ise a s e t o r s e ts o f r u les a nd p roc edures w h ich s hou ld b e f o l lowed i n c arry ing o u t e xper i men ts w ith a nc ien t ma ter ia ls. T he r esu l t o f s uch a l ack o f o rgan isa t ion h as b een , o n t he o ne h and , ac haot ic s er ies o f s ub jec t ive a nd o b ject ive o bserva t ions , a nd , o n t he o ther , aw ide v ar ie ty o f o p in ions a bou t t he r e l iab i l ity a nd v a l id i ty o f e xper imen ta l r esu l ts. Many o bserva t ions h ave b een made a nd r ecorded , b u t t he ir c on tex t a nd r e levance i s o f ten d ub ious i n t he a bsence o f p rocedura l s tandards. C onc lus ions d rawn f ro m e xper i men ts h ave r are ly b een s ub jec ted t o c r it ica l s cru t iny b y impar t ia l o bservers , a nd a l though s imp le r esu l ts , a' yes ' o r ' n o ' s i tua t ion , a re o f ten p ub l ic ised i n p opu lar med ia , t he r ange o f a nswers t o e xp er i men ta l p rob le ms i s f ar g rea ter t han t h is , a nd i s v ery r are ly e xp lored . THEORY Exper i men ta l a rchaeo logy h as c ome t o mean t he e xam inat ion a nd t es t ing o f p ar t icu lar t heor ies a bou t t he c ompos it ion , t he a sse mb ly , a nd t he f unc t ion o f a nc ien t ma ter ia l r ema ins. 2 33
T he e xper i men ts may b e , a nd h ave b een , s ing le e ven ts o r mu lt ip le s er ies o f t es ts , a nd t hey may d ea l w ith m inu te o b jects o r e normous s tructures , s tat i onary o r p or tab le r e ma ins , d o mes t ic c onsumab les o r w eapons o f w ar . They may b e c oncerned w ith t he r aw mater ia ls t ha t w en t t o make a n a nc ien t a r t ifac t , t he h and l ing a nd t he f i t t ing t oge ther o f t he ma ter ia ls t o make t he a r t ifac t , a nd t he u se t o wh ich t he a r t ifact c ou ld h ave b een p u t . T he r ange i s v as t , a nd i s b are ly t ouched b y t he b u lk o f e xper i men ta l w ork s o f ar d one. Why t h is s hou ld b e s o i s ac o mp lex q ues t ion b u t i tp robab ly i s i np ar t a n u nconsc ious r ef lec t ion o f t he u nease w ith wh ich a rchaeo log is ts v iew t he ir ma ter ia ls , a nd t hose who a ctua l ly e xcavate a re b es t p laced t o u nderstand t h is u nease. S URV IVAL F ew a nc ien t s tructures o r o b jec ts h ave s urv ived c o mp lete ly i n tac t , a nd t hose t ha t h ave , h ave s uf fered t hrough b ur ia l , o r e xposure , s o t ha t i n n o c ase c an w e b e s ure t ha t t he e x tan t r e ma ins a ccura te ly r epresen t a l l o f t he c o mp os it ion a nd c haracter o f t he o r ig ina l a t i t s t ime o f manu facture a nd u se. T he p o in t i s s el f e v iden t , y et p robab ly n eeds emphas is b ecause i t immed iate ly o pens u p t he q ues t ion o f v a l id ity .
An e xper i men t may b e d ev ised a nd c onducted w ith
a t ten t ion p a id t o e very o bservab le d eta il , y et t he mode l u pon wh ich t he e xper imen t i s b ased may b e i nadequa te. I t w i l l h ave a l tered s ince i t s a bandonmen t , a nd t herefore t he e n t ire e xper i men t may b e b ased u pon f a lse p rem ises , u n less t he e xcava t ing a rchaeo log ist h as b een s crupu lous i n h is r ecord ing , a nd t he e xper i men ter h as b een c r it ica l a nd s usp ic ious o f t he r ecords a nd t he s urv iv ing r e ma ins. T h is p o in t i s e xa m ined a ga in i n t he s ect ion d ea l ing w ith e xper i men ta l p roof . I fi nadequa te d a ta i s among t he g rea tes t d angers f ac ing t he e xper i men ta l a rchaeo log is t , t hen t hose w orks d ea l ing w ith t he most p er ishab le s ubstances , s uch a s wood , a re l ike ly t o s uf fer t he most . S tones a nd f l in ts a re b as ica l ly u na l tered b y many c ond it ions o f b ur ia l , f i red c lay o f ten s urv ives , a s d o g o ld , c opper a nd b ronze , b u t i ron a nd b one a re o f ten p oor ly-preserved , a nd wood c o mes n ear t he b ot to m o f t he l i st . T h is i s n o d oubt t he r eason f or t he e x trao rd inary a t ten t ion p a id t o wooden o b jects , s uch a s p ar ts o f a rds , b ows a nd b oa ts , t ha t h ave s urv ived i n p ea ts a nd muds. S uch a t ten t ion i s d eserved , b ecause o f t he p resumed h eavy r e l iance u pon w ood f or a l l manner o f o b jects made b y most s oc iet ies i n t he p as t .
Ye t e ven w here w ood h as s urv ived ,
h as b een r ecogn ised a nd r ecovered b y t he e xcava tor , af ur ther p rob le m may a r ise u n less i m med iate s teps a re t aken. S uch o rgan ic ma ter ia l i s f rag i le , a nd w il l o f ten h ave a h igh p ercen tage o f mo is ture i n i t s b ody we igh t , s o me t i mes a s much a s 9 5% wa ter .
The sma l lest amoun t o f d ry ing o u t may w e l l a l ter t he
d i mens ions a nd d istor t t he wood , a nd e ven i fc onserva t ion i s s tar ted a t o nce , t he f in ished p roduct may s uf fer s l igh t ly i n t he a ctua l p rocess. T he s o lu t ion , a ga in , i s f or i m med ia te r ecord ing o f t he p iece b y i t s d iscoverer , r ecord ing o f s uch d eta il a nd a ccuracy t ha t e ven i ft he p iece p er ishes c o mp le te ly , t he i n for ma t ion
f or r econstruc t ion o r s i mu la t ion w i l l b e a dequate.
Wooden a rdg ,
f or e xa mp le , h ave s urv ived a nd h ave b een c onserved , b u t c op ies made o n t he b as is o f t he c onserved a rds a re n ot e xact ly l i ke t he o r ig ina ls a nd t herefore may n ot p er form i n t he s a me manner . b e aware o f t h is p o ten t ia l h azard .
T he e xper i men ta l a rchaeo log ist mus t
He c an d o l i t t le, h owever , o ther t han t o
2 34
estimate the original dimensions of an object if he has no accurate records of it upon its discovery, nor can he do much to account for alteration in size before discovery, through burial in peat or mud. For individual objects, these matters may be of only slight importance, but for an object such as a cart, an ard, or a boat, with several or many p.i.ec�s fitted together, the problems can be of very considerable importance. The hope must be for increased vigilance on the part of excavators, and the readiness of potential experimenters to act We all know of unique objects lying beneath back-filled mud, immediately. or polythene sheets, awaiting more opportune moments for recording and ex amination; this is not good enough. PRINCIPLES The principle behind exoerimental reconstructions is that an objec+ "t'Yla�, be handled freely� may be broken if required and may otherwise be subjected to all sorts of inrlwcitie5 An axe-like tool can be used as an adze, a spade, or a knife, to test its possible functions. A house can be built, lived in, pushed over, or burned down, to see how its components react. And a boat can be built, propelled in different ways, loaded to over-capacity, run aground or even sunk, simply to observe its capabilities. These examples are not frivolous; most of them have actually occurred, and the others should, but they serve to illustrate the potential for experiment. Almost every piece of work done with prethought has yielded useful and valuable information. The information may be, and often is, entirely negative, in that a presumptive implement or process or function does not succeed, but even so this is of value. A flint flake may not work as an engraving tool, even though it has been called a burin by archaeologists, and the demonstration of this non-function is of considerable use to those attempting to reconstruct Stone Age tool kits. A sheet bronze shield may not resist a slashing sword, and, in so doing, other suggestions for the use of such impressive armour may be strengthened. The suitability of most archaeological materials for experimental testing cannot be doubted. The number of actual experiments that have been carried out over the past 100 years is very great, perhaps 250 fully recorded pieces of work, and many more ad hoe experiments barely mentioned in passing. The history of experi menters extends back in the 19th century from Pitt-Rivers, studying earth works, to John Evans, working v:�th stone tools, to Robert Ball, testing musi cal instruments wHh conspicuous, unique, misfortune. Within this corpus of work done, several patterns of endeavour can be seen, and it may be useful to indicate these here. LEVELS OF EXPERIMENT.
DISPLAY
Experiments can be broadly grouped into three separate sections, better described as levels of experime.t!t. The lowest level is that of simulation, wherein a copy is made of an original artifact with attention p2.id only to its visual appearance for display purposes. The materials used may vary from the original, the technology employed in making the copy can be modern, and the copy itself is not tested for its function or purpose. Museum displays are a fair description of this level of experiment, and some would totally exclude the category from experimental archaeology. Yet visual effects can be useful,
235
e ssen t ia l ly t o g ive a t h ird d i mension t o ma ter ia l c u l ture , t o p rov ide a s ca le , a nd n o tab ly t o l ead o n t o f ur ther c onsidera t ion a nd work . A bove t h is , s uch e xper i men ts c anno t r ise , a nd t he ir g rea tes t v a lue a t t he mo men t mus t b e i n t he ir p ub l ic a ppea l wh ich b r ings a pprec ia t ion a nd s uppor t f or f ur ther w ork . E xa mp les o f t h is l eve l o f e xper i men t a re n umerous a nd i nc lude r ebu i l t p reh is tor ic t o mbs , C e l t ic c har io ts , R o man f or ts , a nd p len ty o f h ouses . T he e duca t iona l v a lue o f s uch s i mu la t ions i s i mpor tan t .
An umber o f r a ther
i mpressive e xper i men ta l s truc tures h ave b een b u i l t t o a c t a s f oca l p oin ts f or e duca t iona l p rogra m mes g enera l ly i nvo lv ing y oung p eop le who c an b e g iven t he c hance t o a pprec ia te t he s ca le a nd c harac ter o f f or mer h ouses o r f or ts , o r who c an a c tua l ly a ssist i n t he work a nd t hereby a pprec ia te , i n r e trospec t , t he t asks o f t he ir a ncestors. S o me e xper i men ts o f t h is k ind h ave a pproached a nd a t ta ined t he s econd l eve l o f r esearch . T he p ar t ic ipa t ion o f T e lev is ion a u tho r i t ies i n work a t t h is l eve l i s we lco me , a l though t he ir a pparen t n eed t o p rov ide y es o r n o s o lu t ions may b e i rr i ta t ing t o s o me e xper imen ta l a rchaeo log ists. T he i n teres t o f t he p ub l ic i n s uch p rogra m mes i s impor tan t t o s usta in . LEVELS OF EXPERIMENT .
PRODUCT ION
As econd l eve l o f e xper i men t , wh ich a l l work s hou ld i n t heory a im t o r each , i s c oncerned w i th t est ing f or t he p rocesses a nd p roduc t ion me thods u sed i n t he p as t . H ere t he e xper i men ter i s i nvo lved , n o t o n ly i n mak ing a c opy o r r ep l ica wh ich l ooks l i ke t he o r ig ina l mode l , b u t a lso i n manufac tur ing i tc orr ec t ly . Appropr ia te ma ter ia ls must b e u sed , a nd h ere t he v a lue o f a na lyses o f a nc ien t o b jec ts , t o d e ter m ine t he ir c o mposi t ion , c annot b e e xaggera ted . E xper i men ta l c as t ing o f b ronze a xes , o r t he f l ak ing o f s tone a xes , c an o n ly b e j udged i ft he r aw ma ter ia ls h ave e xac t ly t he s ame c harac ter ist ics a s t he o r ig ina ls . T he p o in t i s o bv ious , a nd a ga in f or wood i ti s o f p ara moun t i mpor tance t ha t where p ossib le t he s a me t ype o f wood , i t s a ge , g ra in a nd c ond i t ion s hou ld b e u sed i n a ny a t te mp ted r econstruc t ion . E xper i men ts c oncerned w i th p o t tery p roduc t ion h ave p robab ly s u f fered f ro m a l ack o f c are , n o t i n b u i ld ing t he k i lns o r i nt he f i ring , b u t i n t he c lays a nd g r i ts c hosen a s r aw ma ter ia ls f or t he p o tt ery v esse ls a nd f or t he k i lns . H owever , i ti s n o t p ossib le t o s ta te c a tagor ica l ly t ha t t he e xper i men ts h ave s uf fered i n t h is w ay , b ecause t hese f eatures a re r are ly men t ioned i n p ub l ished r epor ts ; t here a re n o tab le e xcep t ions . F or wood , t he n ecessi ty f or c are i n c hoosing a ppropr ia te ma ter ia ls i s c lear . As econd e le men t i n e xper i men ts c oncerned w i th p roduc t ion me thods i s t ha t o f a n a ppropr ia te t echno logy . T he g rea tes t c are may b e t aken i n c o l lec t ing t he r aw ma ter ia ls , b u t t he work ing o r a sse mb ly o r s uch ma ter ia ls s hou ld b e e n t ire ly i n k eep ing w i th a l eve l o f t echno log ica l a b i l i ty a ppropr ia te t o t he s oc ie ty wh ich made t he o r ig ina l o b jec ts. We d o n o t k now h ow much e f fec t ab u l ld ozer w i l l h ave u pon a r econstruc ted e ar thwork , o f a n e lec tr ic d r i l l u pon a wooden f ra mework f or a R o man g a te ; t he f i rs t h as a more v isua l ly s ubstan t ia l e f fec t u pon t he r econstruc t ion , b u t f r ic t ion c rack ing a nd f ray ing a l l h ave a p ar t t o p lay i n t he b u i ld-up o f p ressures u pon wooden t imbers d ur ing d r i l l ing a nd h a m mer ing o f p egs a nd n a i ls . T h is p rob le m o f t echno logy i s p erhaps t he most d i f f icu l t f or e xper i men ters t o s o lve , b ecause t here i s al im i t t o t he d egree o f o ur k now ledge a bou t p reh istor ic o r e ar ly t echno logy a nd b eyond t h is , e xp er i men ters a re i n d angerous t err i tory , where s ub jec t ive u nsubstan t ive o p in ions a re r i fe.
T he e xper i men t mus t o bv ious ly b e c onduc ted w i th a s c lose a n a pprox i2 36
ma t ion t o a ncien t t echn iques a s may r easonab ly b e a ssumed a nd e xpec ted , a nd a s l ong a s t he r epor ted r esu l ts c lear ly s ign i fy t he p rocedures u sed , t hen a pp ropr ia te a ssess men t may b e made b y o thers a s t o t he ir s u i tabi l i ty a nd s ign if icance . I fi ti s p ossib le t o emp loy o n ly t hose p rocedures a nd e qu ip men t l ike ly t o h ave b een a va i lab le i n t he c on te mporary s oc ie ty , t hen f ur ther e xper i men ta l a dvances may b e made .
On t he o ne h and , t he imp le men ts u sed c an t he mse lves
b e o bserved f or t he ir own c apab i l i t ies , a nd t he wear o r b reakages t ha t o ccur . On t he o ther , t he more d i f f icu l t q uest ion o f t ime c an b e p osed .
I n e xper i men ta l
p roduc t ion o f s tone t oo ls , f or e xa mp le , t he h a m mer-stones o r wooden ma l le ts c an b e r ecorded f or b ru ising o r c h ipp ing , a nd t he t ime t aken t o p roduce a s tone a xe c an b e r easonab ly e st i ma ted .
I n c ast ing a b ronze i mp le men t , o r f org ing
a n i ron t oo l , t he e qu ip men t u sed , f urnaces , c ruc ib les , mou lds , h a m mer , a l l c an a nd s hou ld b e c are fu l ly r ecorded b e fore , d ur ing a nd a f ter u se .
T h is p oin t
a ga in i s s e l f-ev iden t , b u t i t s r e l iab i l i ty i s o n ly a ccep tab le i fa ppropr ia te e qu ipmen t a nd t echno log ies a re u sed .
T he e lapsed t i mes f or s uch p rocedures ,
whe ther measur ing t he r a te o f e xcava t ion o f c ha lk , o r t he t ime t aken t o f e l l t rees w i th a s tone a xe , a re n o t s o e asi ly a ccep tab le u n less t he e xper i men ters a re e n t ire ly f am i l iar w i th t he ir ma ter ia ls a nd t echno log ies , a nd whe ther t h is i s e ver c o mp lete ly p ossib le i s a ma t ter f or d eba te .
H ere , h owever , i s ap o in t
where a n e x tre me ly v a luab le s ource o f i n for ma tion a ppears. ETHNOGRAPHY I tc an l eg i t i ma te ly b e s a id t ha t e thnography i s o ne o f t he most n eg lec ted f ie lds o f e xper i men ta l a rchaeo logy , b ecause a l arge b ody o f d a ta e x is ts b o th i n l i tera ture a nd i n t he f ie ld wh ich c ou ld b e o f c onsiderab le v a lue .
S oc ie t ies wh ich
t oday a re t o ta l ly i so la ted f ro m t he ma in t echno log ica l a dvances o f t he wor ld a re r are , a nd b eco m ing r arer , b u t much h as a lready b een r ecorded .
D e ta i led
r ecords o f s tone t oo l manu fac ture , i ron sme l t ing , f ores t c learance , h ouse b u i ld ing , p o t tery f ir ing , a nd many more , p rov ide u n ique g u ides t o t he t echn olog ies o f t he p as t .
T hey a re u n ique b ecause t he p eop le p rac t ising t he m k now ,
o r k new , n o o ther ways a nd were e n t ire ly f am i l iar w i th t he ir ma ter ia ls a nd t he ir p rocedures, a nd t he p rec ise r easons f or s e lec t ing t he m a l l .
I ti s n o t
l eg i t i ma te t o a ccep t a l l t he d e ta i ls o f s uch o bservab le work a s r epresen t ing e xact ly t hose o f t he p as t , b u t a s ag enera l g u ide t o l ike ly a c t ions e thnograph ic r ecords a re i nva luab le .
T he c r i t icis m o f ten l eve l led a t s uch r ecords , t ha t
t hey r epresen t s i tua t ions f ar r e moved i n b o th t i me a nd s pace f ro m t he mi l ieu o f t he a nc ien t s oc ie ty u nder e xa m ina t ion i s al eg i t i ma te c r i t ic is m y e t c anno t t o ta l ly s erve t o d is m iss t he u se o f s uch a n i n for ma t ion s ource .
I n c er tain
c ases i t may b e r easonab le t o o ver look e nv iron men ta l d i f ferences ; p rocesses s uch a s i ron work ing may b e ac ase i n p oin t . i n e nv iron men t w i l l h ave b een o f ma jor e f fec t ;
s i mp le f or ms o f a gr icu l ture i n
t rop ica l o r setrop ica l r eg ions s hou ld n o t b e u sed a s p rac t ices i n n or thern l a t i tudes.
sma l l
I n o thers , d i f ferences g u ides t o p reh istor ic
Wi th c are , t he e xper i men ter w i l l f ind a v ast
s ource o f ' exper i men ta l ' d a ta a lready a va i lab le , a nd o ne m igh t h ope f or a c o mp i la t ion o f s uch ma ter ia l f ro m a n e thnographer r a ther t han a s oc ia l a n thropo log ist .
2 37
LEVELS OF EXPER IMENT .
FUNCT ION
At h ird a nd f ina l l eve l o f e xper i men t i s c oncerned w i th t he f unc t ion o f t he a r t ifac t , t he u se o r u ses t o wh ich t he o b ject i s p resu med t o h ave b een p u t . Th is l eve l i s al og ica l s tep u p f ro m t ha t d ea l ing w i th t he p roduc t ion me thods , a nd t here a re f ew e xper i men ts t ha t c an p roceed d irec t ly t o f unct iontest ing w i thou t t he n ecessi ty f or a ccuracy a nd r e levance i n manu fac ture .
I t wou ld b e wor th less
t o t est a n e arthen b ank f or e rosion a nd w ea ther ing i fi th as b een h eaped u p b y e ar th mov ing mach ine , b u t i ti s l i t t le b e t ter t o t est a n a ccura te c opy o f a wooden a rd d ragged b y c ha in a nd t rac tor ; b o th a spec ts must b e r e la ted i n c oncep t a nd a pproach .
T he v isua l a ppearance o f a wooden b oa t migh t n o t b e a f fec ted b y
'
t he u se o f modern t echno log ies i n i t s mak ing , b u t i t s h and l ing a nd p ossibly i t s eawor thiness migh t b e a l tered i n s o me sma l l ways t ha t c ou ld c o mb ine t o a ff ec t t he c onc lus ions d rawn f ro m t he e xper i men ts . o f a l tera t ion
The q uest ion o f t he e x ten t/
c an p robab ly n ever b e r eso lved u n less c o mpara t ive t ests a re
d one , a nd t h is wou ld b e a n e xpens ive p rocess.
T he g enera l p o in t , h owever ,
mus t b e c lear , t ha t f or f unc t ion t es t ing , t he o b jec t must b e made i n a n a pprop r ia te manner .
T ha t t here i s s cope f or s o me c ho ice i n t h is w i l l b e emphasised
l a ter when t he a pproach t o e xper i men t i s d iscussed . T here a re t wo a spec ts i n t h is f unc t iona l work t ha t a re v i ta l , y e t s o me t i mes i gnored o r n eg lec ted .
T he f irst i s t ha t o f man ipu la t ion a nd o pera t ion ;
s econd i s e nv iron men ta l .
t he
T he a c tua l me thods b y wh ich o b jec ts a re u sed t o
c arry o u t c er ta in f unc t ions r equ ire more t hough t t han u n tu tored v o lun teer l abour i s l ike ly t o g ive .
T he r eason why s tone a xes s o me t i mes c o mpare b ad ly w i th
s tee l a xes , i n c hopping t rees , i s i n t he ir mode o f u se , b ecause t he a ng le o f b low , a nd t he b ack l i f t ,, o f as tone a xe i s t o ta l ly u n l ike t ha t o f as tee l a xe t o wh ich modern man i s a ccusto med .
T he l ack o f s uccess i n b reak ing u p a nd
t ranspor ting c ha lk a nd e ar th , u sing a n t ler p icks , b one s hove ls a nd wooden b aske ts i s i n p ar t d ue t o o ur u n fa m i l iar i ty w i th t hese u nusua l imp le men ts.
T he
s a me d i f f icu l t ies were p resen t i n e f for ts t o c u l t iva te s o i ls w i th a nc ien t f or ms o f a rd , wh ich i nvo lved e n t ire ly t heore t ica l a nd s ub jec t ive me thods o f t ra in ing t he d raugh t a n i ma ls , d ev ising t he h arness , a nd man ipu la t ing t he a rd ;
t he r e-
s u l ts were c onsp icuously s uccessfu l a s e xper i men ts b ecause o f t he c are t aken i n r ecord ing a nd p ub l ish ing t he o bserva t ions a nd p rob le ms . T he a rd e xper i men ts were a lso c oncerned w i th t he e nv iron men ta l c ond i tions t ha t a lways a f fec t work o f t h is s or t .
H ere t he q uest ions o f c leared g round , o ld
t ur f , s o i ls a nd c l i ma te were v ita l i ft he e xper i men ts were t o h ave a ny r e lev ance i n t er ms o f p as t s i tua t ions :
o ther t ests w i th o ther e qu ip men t a re n o t s o
d ependen t u pon p hysica l e nv ironmen ta l c ond i t ions wh ich ma tch t hose o f t he p as t , b u t e ven s o t h is i s a n a spect we l l wor th c are fu l c onsidera t ion .
Prob le ms o f
n av iga t ion i n t he p ast may h ave b een d i f feren t f ro m t hose a t t he p resen t , c ert a in ly i n a reas where ma jor p hysica l c hanges h ave o ccurred , b u t i ti s l i ke ly t ha t e xper i men ts c oncerned w i th e ar ly c u lt iva t ion r equ ire t he g rea tes t a t ten t ion t o ma t ters o f e nv iron men ta l c ond i t ions.
T h is s hou ld n o t i gnore o r e xc lude t he
g enera l c oncep t o f t he s oc ia l b ackground w i th in wh ich e xper i men ters o pera te , w i th o u t looks o n e cono m ies , t ime , mo t iva t ion , i ngenu i ty a nd g enera l p h i losophy o f l i fe , a l l o f wh ich may we l l d i f fer f ro m t hose o f e ar lier p eop le a nd wh ich may a f fect t he e xper i men ta l work i n s ub t le a nd u nconsc ious ways.
2 38
T he t hree l eve ls o f e xper i men t s uggested a bove a re n o t mu tua l ly e xc lusive , a nd s o me f ew e xper i men ts h ave b een a pproached a t a n i n ter med ia te l eve l , g ene ra l ly b e tween D isp lay a nd P roduc t ion .
T he t hree l eve ls may b e s u m mar ized :
Exper i men ta l L eve l D isp lay
P roduc t ion
Func t ion
Requ ire men ts A ppearance Ma ter ia ls T echno logy Env iron men t U se REPET IT ION AND S ER IES TEST ING Among t he e xper i men ts c oncerned w i th t he f unc t iona l t est ing o f a nc ien t r e ma ins , s evera l may b e d is t ingu ised b ecause t hey a ch ieved f ar g rea ter r e l ia b i l i ty t hrough r epe t i t ion .
R epe t i t ion i s o f ten b or ing , whe ther more s o i n
wr i t ing t han t a lk ing i s u ncer ta in , b u t i n e xper i men ta l a rchaeo logy t he a b i l i ty t o s us ta in r epea ted
t ests h as a l mos t a lways l ed t o a ugmen ted r esu l ts .
Repe-
t i t ion i n e xper i men ts c oncerned w i th t he u nderground s torage o f g ra in h ave s hown t he r e la t ive e ase b y wh ich s eed-gra in c ou ld b e p reserved b y I ron Age man , b u t i ti s o n ly b y al ong s equence o f t ests t ha t t h is f ac i l i ty h as b eco me a pparen t ;
i t was a q ues t ion o f g a in ing e xper t ise i n t he work a nd i n t he sma l l
r e f ine men ts i n d e ta i l , o n ly p ossib le t hrough a t r ia l a nd e rror a pproach . S er iestests a re b asica l ly t he s a me a s r epe t i t ion e xcep t t ha t h ere a c ons cious e f for t i s made t o l ead f ro m o ne r esu l t , r epea ted i fr equ ired , t o as econd o r t o ar ed irec t ion o f e f for t .
F ro m a n i n i t ia l i n terest i n b asic a rchery , S axon
T . P ope e x tended h is e xper i men ts t o i nc lude a g rea t v ar ie ty o f b ows , a rrows , b owstr ings , a rrowheads a nd t arge ts , e ach t es t b u i ld ing u pon p rev ious t ests a nd s uggest ing f ur ther work .
Ano ther p rogra m me r e levan t h ere i s t hat c on-
c erned w i th e ar thwork e rosion a nd d ecay , where a s er ies o f e xa m ina t ions o ver al ong p er iod o f t ime s hou ld a ugmen t o ur k now ledge o f t he p rocesses b y wh ich p reh is tor ic e ar thworks a ch ieved t he ir a ppearance t oday .
R epe t i t ion a nd s er ies
o f e xper i men ts h ave o ne o ther e le men t p robab ly wor th men t ion ing h ere , a nd t h is c oncerns t he p ersona l i t ies i nvo lved i n t he work .
A l though i ti s t rue t o
s ay t ha t an ew a pproach a nd f resh i nsigh t i n a n e xper i men t may e nsue f ro m a c hange i n t he p ersonne l t ea m , t he ma in tenance o f b o th c on t inu i ty a nd u nder s tand ing i n e xper i men ta l work i s e x tre me ly i mpor tan t a nd c an b es t b e a ch ieved b y t he c onstan t p resence o f a t l east t he i nst iga tor a nd/or c h ie f t echn ic ian . P ersona l i nvo lve men t i n e xper i men ta l a rchaeo logy i s g enera l ly ma in ta ined t hroughou t t he work , t hrough s heer i n terest a nd d ed ica t ion , a nd i ti s p robab ly n o table t ha t t hose f ew c ases where t he s er ies t ests h ave l agged b eh ind t he p lann ed p rogra m me h ave c oncerned r a ther l arger t ea ms o f s pec ia lists w i th n o o ne s ing le l eader o r d irec tor .
P ersona l i nvo lv men t
i s impor tan t , a nd e xce l len t
d e monstra tors o f d ed icat ion a nd t o ta l i m mersion i n t he p ro jec ts a re n o t h ard t o f ind a t p laces s uch a s L i t t le Bu tzer a nd L e jre , n or a re t hey l ess a bundan t
2 39
i n e xper i men ts n o t i nvo lv ing f u l lt i me s a lar ied s ta f f , i n s i tua t ions o f e x tre me h ardsh ip a nd s o me d anger . SCALE MODELS N o t a l l who w ish t o e xper i men t w i th a rchaeo log ica l ma ter ia l c an a f ford t he t ime o r money t o c onduc t ma jor p rogra m mes o f work wh ich may i nvo lve h eavy a nd a bundan t r aw ma ter ia ls , mass ive e xpendi ture o f e f for t i n t he t echno logy , a nd l eng thy p er iods o f f unc t ion t es ts. An e xper i men t c oncerned w i th a mega l i th ic t o mb , f or e xa mp le , wou ld i nvo lve q uarry ing a nd d ressing s tone , t ranspor ta t ion , av ery l arge work f orce , a nd t he o rgan isa t ion o f a s i te t o h ouse t he e xper i men t .
An i ngen ious way o u t o f t h is i mpasse i s t o
r educe t he e xper i men t i n o ne o f t wo ways. T he f irst , a s emp loyed b y Eras mus i n Mex ico , was t o c onduc t s hor t b u t f u l l s ca le e xerc ises a s s a mp les o f t he e n t ire p rocedures ; o bserva t ions were made o f s hor t-ter m q uarry ing a nd d igg ing , t ranspor ta t ion , b u i ld ing a nd f ac ing o f s tone a nd e ar th wa l ls , a nd t hese t ime a nd e nergy r ecords were t hen u sed t o c a lcu la te t he d ra in o n ap reh is tor ic s oc ie ty e ngaged i n e rec t ing a massive , p ar t ly s urv iv ing monu men t . t he o rgan isa t ion o n t he p ar t o f t he e xper i men ter was c ons iderab le .
E ven s o ,
T he a l terna t ive way t o l ower t h is c ost-fac tor i s t o r educe t he e n t ire e xper i men t t o a sma l l s ca le ,
1/1 0 o r
e ven l ess.
S uch r educ t ions h ave b een
a t te mp ted f or e ar thworks a nd f or mega l i ths , a nd w i th v ary ing r esu l ts .
A t
f irst s igh t , t o a t te mp t t o u nderstand s uch s truc tures b y m in ia ture mode ls s ee ms a bsurd , a nd t here c an b e l i t t le d oub t a bou t t he u ncer ta in ty o f o bservat ions c onerned w i th e rosion a nd wea ther ing o f sma l l d o mes o f e ar th .
Ye t o ne
s ca led e xper i men t o n t he mega l i th ic monu men t S tonehenge h as g enera l ly b een a ccep ted a s d e monstra t ing p rec ise ly h ow t he l arge u pr igh ts were e rec ted o n t he s i te ; t he e ng ineer ing work i nvo lved i n t he e xper i men t c onsisted o f e xac t s ca led h u mans , r opes , t imbers a nd s tones , w i th much p rac t ica l a nd t heore t ic a l r eason ing a t tached . I t wou ld s ee m , h owever , t ha t many e xper i men ts a re o f s uch a c harac ter a s t o r e move much h ope o f as uccessfu l s ca le mode l a pproach ; f or b oa ts , mode ls h ave o f ten b een u sed i n t es ts f or s eawor th iness , b u t b eyond t h is i ti s h ard t o v isua l ize a d om inan t r o le f or min ia tures. Af ina l s tage i n s ca led e xper i men ts , i fc os ts a nd o ppor tun i t ies a re u nr ea l ised , i s o f c ourse t o d o n o a c tua l work o f r econs truc t ion o r s i mu la t ion , b u t t o d ev ise a nd c onduc t t he e x per i men t p ure ly o n t heore t ica l g rounds. I t s hou ld b e p ossib le t o p red ic t e xac t ly h ow a s truc ture c ou ld b e p u t t oge ther , o r h ow i t wou ld r eac t t o c er ta in c ond i t ions , g iven a l l o f t he p roper t ies o f t he ma ter ia ls a nd t he s treng th o f t he a genc ies a c t ing u pon t he m .
T he e rec t ion o f
p ar ts o f S tonehenge c an b e v isua l ised i n t h is way , j us t a s t he c urren t , w ind a nd n av iga t ion r equ ire men ts f or P o lynesian c o lon isa t ion c an b e c a lcu la ted . T he p roo f o f t he t heory , h owever , must s t i l l l i e i n t he a c tua l e ven t , where a l l t he o ther sma l l a nd s ee m ing ly u n i mpor tan t f ac tors , s uch a s t e mpera men t a nd v ar ia t ions i n e qu ip men t , a s we l l a s e xcep t iona l c ond i t ions , may b e i nadver ten t ly a ppl ied . RELIAB IL ITY Fro m t he f orego ing i ts hou ld b e c lear t ha t av ar ie ty o f e xper i men ts h ave a lready b een c arr ied o u t , u sing d i f feren t a pproaches a nd p roducing r esu l ts o f 2 40
v ary ing a ccep tab i l i ty .
T here a re f ew h ard r u les i n e xper i men ta l a rchaeo logy
e xcep t t hose o f h onesty , s e l f-cr i t ic is m a nd d e ter m ina t ion .
Y e t w i th a l l t h is ,
t here s t i l l r e ma ins t he p rob le m o f h ow t o a ssess t he r esu l ts o f e xper i men ts , h ow much r e l iance t o p lace u pon t he a nswers t ha t emerge . F irst , t he r esu l ts s hou ld b e r epea tab le , i n o rder t o d e mons tra te t ha t c hance a lone h as n o t d et er m ined t he r esu l t .
As ing le s uccess fu l f ir ing o f ap ar t icu lar t ype o f
p o t tery v esse l mus t b e r epea ted s o t ha t t he p rocess c an b e s hown t o p rov ide ac onsisten t r esu l t .
As oph ist ica ted s tone imp le men t , s uch a s aP a laeo ind ian
p ro jec t i le h ead o f f l in t , mus t b e p roduced t ime a nd t ime a ga in i n o rder t o e l im ina te a f reak p ercussion b low o r u nusua l r aw ma ter ia l t ha t migh t h ave y ie lded a f irst s uccessfu l c opy .
As ing le s ea t r ia l o f ab oa t s hou ld n o t b e
c ons idered e nough t o p rove , e ven d isprove , i t s c apabi l i t ies. S econd , i n a ssessing r esu l ts i ti s i mpor tan t t o b e aware o f t he o p t ions t hus p roduced .
One s o l i tary a nswer may n o t emerge f ro m a t es t , a nd t here may
we l l b e s evera l p ossible s o lu t ions t o a n e xper i men ta l p rob le m .
As tone a xe-
l ike t oo l may n o t f unc t ion a s a n a xe , b u t may work we l l a s a n a dze ; i tc ou ld a lso s erve a s ah oe , o r s pade , o r ma t tock , o r mea t c leaver a nd i fa l l o f t he p ossib le f unc t ions a re n o t e xp lored , t hen t he r ange o f o p t iona l a nswers r ema ins w ide .
On ly b y s er ies-test ing c an t he l i st b e r educed b y e l im ina t ion .
And i tw i l l b e more o f ten a q uest ion o f e l im ina t ion r a ther t han o f s ubstan t iat i on ; i ti s e asier t o p rove t ha t a n o b jec t d oes n o t work a t ap ar t icu lar t ask t han i ti s t o s how t ha t t he o b jec t d id s erve o ne a nd o n ly o ne f unc t ion i n t he p as t .
H ere , m icroscop ic e xa m ina t ion f or t races o f wear o n imp le men ts c an
h e lp .
F or tuna te ly , f or many a nc ien t o b jec ts a nd s truc tures o n ly o ne o r t wo
p oss ib le f unc t ions n eed b e e n ter ta ined ; ab oa t i s p resumab ly mean t f or wa ter a nd s hou ld t here fore f l oa t .
L ikew ise , ah ouse i s l ike ly t o h ave b een b u i l t
t o s he l ter s o me th ing b enea th i t s r oo f , i fi th ad a r oo f . QUEST IONS One way b y wh ich e xper i men ta l a rchaeo log ists c an r educe t he n umber o f o p t iona l a nswers i s t hrough a c are fu l a pproach t o p ar t icu lar p rob le ms .
B y
s e t t ing o u t t o t est i f ah ouse i s c apab le o f w i ths tanding f ire i n t he r oo f , o r i fi t c an b e o ccup ied i n s evere w in ter , t he a rchaeo log ist c an p ose s pec i f ic q uest ions , s e t u p h is e xper i men t a nd r ecord ing p rocedures , a nd e stab l ish h is a nswers w i th in r e la t ive ly n arrow l im i ts .
I fh e d oes n o t p ose p ar t icu lar q uest ions , h e
w i l l n o t k now wh ich l eve l o f e xper i men t h e h opes t o a ch ieve , a nd w i l l b e l e f t w i th a v as t r ange o f p o ten t ia l p rob le ms , s o me o f wh ich h e w i l l n o t h ave e ven c ons idered t o e x is t .
T he p re l im inary p osing o f q ues t ions , t he q uest ion ing
a pproach , i s o ne o f t he mos t impor tan t a spec ts i n t he t heory o f e xper i men ta l a rchaeo logy . A s a n e xa mp le , h ouse b u i ld ing d e mons tra tes t he p o ten t ia l o f t he q uest ioni ng a pproach , a nd t he r e levenace i th as t o t he p rocedures a dop ted .
I fa n
e xper i men t i s t o t est t he ma ter ia ls , t ime a nd mo t ion s tud ies , i n t he e rec t ion o f t he b u i ld ing , t hen g rea t c are i n r ecord ing s uch d e ta i ls w i l l h ave t o b e e xpended , a nd o n ly a ppropr ia te me thods c an b e u sed .
I ft he b u i ld ing i s t o
b e d es troyed b y f ire , i t s r e f ine men ts p erhaps n eed n o t b e s o e x tensive , b u t i t s e xac t a sse mb ly a nd t he p osi t ion o f e ach o f i t s me mbers must b e n o ted , a nd i t s p hysica l c ond i t ion must b e r ecorded b e fore t he c on f lagra t ion .
2 41
I ft he
b u i ld ing i s t o s erve o n ly a s ad isp lay a rea , o r t o h ouse museum e xh ibi ts , t hen i t s p rec ision i n e rec t ion n eed n o t b e s o c are fu l ly c on tro l led .
T he s a me
g enera l c ond i t ions w i l l a pp ly t o o ther e xper i men ta l s ub jec ts , i nc lud ing b oa ts , s tone t oo ls , a nd e ar thworks , a l though t he d e ta i ls w i l l n a tura l ly d i f fer .
T he
t hree l eve ls o f e xper i men t n o ted a bove a re a ppropr ia te h ere , a l though t hey a re p erhaps t oo r ig id ly e xc lusive a t t he p roduc t ion a nd f unc t ion l eve ls . PROOF H aving c are fu l ly d ev ised a p rob le m-or ien ta ted a pproach t o a n e xper i men t a nd h av ing r e l ig iously o bserved a l l o f t he p r inc ip les , t he e xper i men ta l a rchaeo log ist w i l l b e l e f t w i th a s e t o f r esu l ts o r , r a ther , r ecords o f t he o bserva t ions made .
T he q uest ion o f p roo f t hen h as t o b e f aced .
r e l iance c an b e p laced o n as e t o f r esu l ts?
H ow much
A rchaeo log ica l p roo f i s a lways
h ard t o d e monstra te , a nd t he p rogressive r educ t ion i n i n for ma t ion i s we l l k nown : a nc ien t e v idence ( ob jec t o r a c t iv i ty ) t o ta l b ur ied e v idence
>
>
s urv iv ing e v idence i n t he g round
>
a rchaeo log ica l r ecovery o f e v idence > a rchaeo log ica l u nders tand ing o f e v idence . T he e xper i men ta l a rchaeo log ist i s p robab ly n o b e t ter a nd n o worse t han t h is .
A l l o f t he a va i lab le e v idence must b e u sed , a nd t he e xper i men ta l r e-
s u l ts s ub jec ted t o ab a lanced o p in ion wh ich w i l l s ta te t he u ncer ta in t ies a s we l l a s t he a ch ieve men ts . Where a t est h as e l im ina ted a p ossib le a nswer , where a p resumed f unct ion d oes n o t work , t hen t he ' nega t ive ' a nswer i s a lmos t c er tain ly a p osi t ive o ne , a nd t ha t a nc ien t f unc t ion c an b e s a id n o t t o h ave b een p er for med b y t ha t t oo l .
On t he o ther h and , i fac er ta in i mp le men t
d oes f unc t ion s uccessfu l ly i n p er for m ing a c er ta in a c t , i tn eed n o t n ecessar i ly mean t ha t t he t oo l was a c tua l ly u sed i n t h is way i n t he p ast .
I t may h ave
p er for med a no ther f unc t ion , n o t c onsidered b y t he a rchaeo log ist .
T he a nswers ,
t he r e l iab i l i ty o f r esu l ts , c lear ly w i l l n o t b e s i mp le y es o r n o s i tua t ions , b u t p resu mp t ive a nd p ossib le a nswers.
I ti s n o t o f ten t ha t p roo f a bso lu te i s
c la i med , y e t t here h ave b een s o me ; t he work o f T own ley J ohnson o n Bush man r ock a r t a nd t he ir p a in ts a nd med ia q u i te c lear ly i nd ica ted o n ly o ne p osi t ive a nswer t o t he med ia p rob le m , a nd t here fore t ha t an swer was t he c orrec t o ne s o f ar a s t he e v idence s uggested .
Work o n Bronze Age s h ie lds was l ess
c onc lusive , b u t i td e monstra ted t he u nsu i tab i l i ty o f me ta l s h ie lds f or a c tua l p hysica l b a t t le , a nd t he s a t isfac tory q ua l i t ies o f l ea ther s h ie lds f or b a t t le ; t he n ega t ive r esu l t ( me ta l ) s ee ms c onc lusive , b u t t he p osi t ive r esu l t ( l ea ther ) c ou ld b e o n ly o ne o f an u mber o f u ses f or t hese s h ie lds.
Archaeo log ists
s hou ld n o t b e d is mayed b y t hese u ncer ta in t ies ; t hey a re i nheren t i n p reh is tory a nd i l l-recorded e ar ly h istor ies.
T he work o f H eyerdah l i s a no ther c ase i n
p o in t b ecause a l though h e h as b een a b le t o s how t ha t v oyages i n r eed b oa ts a cross t he
A t lan t ic a re p ossib le , h e h as n o t c la i med t ha t t h is p roves t ha t
s uch v oyages d id t ake p lace i n t he p ast . modes t a bou t t he ir r esu l ts .
2 42
N o t a l l e xper i men ters h ave b een s o
VALUES T he v a lue o f e xper i men ts i s t ha t t hey f orce t he a rchaeo log is t t o t h ink a bou t a l l o f t he c haracter is t ics a nd q ua l i t ies o f h is ma ter ia l , a nd n o t j ust t hose t ha t a re s uper f ic ia l ly e v iden t .
T he e ssen t ia l f ea tures o f a r t i fac ts ,
whe ther sma l l p or tab le t oo ls o r l arge p er manen t s truc tures , a re n o t a lways t hose mos t r ead i ly a pparen t , a nd e xper i men ts a re t he o n ly way b y wh ich t he a rchaeo log is t c an c o me t o u nderstand t he p rac t ica l r easons f or t he s e lect ion a nd man ipu la t ion o f ma ter ia ls i n t he p ast .
E xper i men ts , t hen , c rea te o p-
p or tun i t ies f or a n ew a pproach t o a rchaeo logy , o ne c oncerned w i th t he e cono m ic r equ ire men ts o f a nc ien t man , a nd t here fore b asic t o o ur u nderstand ing o f p as t h u man s ocie t ies . ACKNO WLEDGE MENTS T he h istory o f e xper i men ta l a rchaeo logy i s l ong , a nd i ti s o n ly b y o bservat ion o f t he r ange a nd c harac ter o f t h is work t ha t t rends c an b e s een , p rincip les d e ter m ined , a nd l eve ls o f e xper i men t d educed .
Wha t h as b een s a id i n t h is
p aper r epresen ts o n ly o ne v iewpoin t o f t he t o ta l work a lready d one , a nd t he a u thor i s t here fore e n t ire ly d ependen t u pon t he p rac t ica l e xper i men ts o f o thers .
I nd iv idua l workers h ave n o t g enera l ly b een s ing led o u t h ere , n or
r e ferences l i sted t o p ar t icu lar e xper i men ts ; many o f b o th a re n o ted i n t he b ook Archaeo logy b y Experi men t ( Hu tchinson , London , 1 973 ) .
2 43
1 8 .
ASPECTS OF EXPER IMENTAL BOAT ARCHAEOLOGY S ean Mc G ra i l S u m mary
The a u then t ic i ty o f ab oa t r ep l ica s hou ld b e i nvest iga ted b e fore d educ t ions a re made a bou t t he c apabi l i t ies o f t he o r ig ina l v esse l . T h is p oin t i s i l lustra ted b y r e ference t o t he 1 893 r ep l ica o f t he G okstad s h ip , a nd t o t he r ecen t G reenw ich f aer ing r ep l ica . B oat r ep l icas r epresen t ah eavy i nvest men t a nd t he d ec ision t o b u i ld s hou ld b e p receded b y c os t/bene f i t a na lysis wh ich s hou ld i nc lude c ons idera t ion o f t he r ep l ica 's l ong t er m u se . I n g enera l , t here a re s evera l s o lu t ions t o t he p rob le m o f h ypothe t ica l ly r econs truc t ing a n i nco mp le te b oa t f ind , b u t f u l l s ize b oa t r ep l icas h ave o n ly l im i ted a dap tab i l i ty o nce t he ir main d esign p ara me ters a re e s tab l ished .
An i n ter med ia te s tage o f t heore t ica l
mode l b u i ld ing i s t here fore r eco m mended , i n wh ich i n ter-d iscip l inary t echn iques a re u sed t o i nvest iga te t he v ar ian t f or ms.
Iv ery much r egre t t ha t i tp roved impossib le f or A lan H inks t o p resen t a p aper a t t h is S y mposium .
H e i s c ha ir man o f J .. H inks a nd S on , t he N or th
Devon s h ipbu i lders ( Farr , 1 976 : 1 7 , 1 8 ) , a nd u nexpec ted ly h as t o c arry o u t s ea t r ia ls o n ar ecen t ly c o mp le ted s h ip .
We wou ld h ave l earned much f ro m
h is e xper ience o f c o m merc ia l ly b u i ld ing r ep l icas o f a nc ien t b oa ts. Ih ope t ha t o ne d ay we may h ear h im a t a no ther f oru m -p ossib ly o n s i te i n h is b oa tyard , a s r eco mmended i n a no ther c on tex t b y Hass löf ( 1972 ) .
If e l t i ti mpossib le
t o i nv i te o thers t o p repare a p aper o n t h is t op ic a t s hor t n o t ice , a nd t here fore Ir e luc tan t ly u nder took t h is t ask myse l f . BOAT REPL ICAS L a ter i n t h is S y mposium T i mo thy S ever in w i l l d escr ibe t he b u ild ing o f h is s k in b oa t B rendan a nd h ow h e s a i led h er t h is y ear f ro m I re land t o I ce land . Brendan i s t he l a test i n al ong l i ne o f b oa t r ep l icas , t hough n o t a l l c ou ld b e c lassi f ied a s a rchaeo log ica l e xper i men ts .
P au l J ohns tone o f t he BBC
" Chron ic le" p rogra m me , who b u t f or h is u n t i me ly d ea th wou ld h ave p resen ted ap aper a t t h is S y mposiu m , h ad t raced d e ta i ls o f ar ep l ica t r ire me b u i l t f or Napo leon I I i n 1 861 ( Eve i l lard , n .d . 2 33 ) ; t h is i s p ossib ly t he e ar l iest r epl i ca o f wh ich we h ave r ecords .
J ohnstone h i mse l f was i nvo lved i n t he b u i ld ing
a nd f i lm ing o f s evera l e xper imen ta l c ra f t : f irs t ly A tk inson 's S tonehenge e xper i men t i n 1 954 , when a r ep l ica b lues tone was t ranspor ted b y a mu l t ip le
2 45
F ig . 1 8.1
A r ep l ica o f t he Nyda m b oa t b u i lt i n 1 935 f or u se i n aG erman f i l m.
H . Äker lund.
F ig. 1 8.2
V ik ing , Magnus Andersen 's 1 893 r ep l ica o f t he G okstad s h ip . Norsk S j9 S far ts museu m , O s lo.
F ig . 1 8.3
V ik ing i n t he N or th S ea , w ith a f oresa i l i n a dd it ion t o h er s quare ma insa i l.
Magnus Andersen .
F ig . 1 8.4
I l ug in . T he 1 949 Dan ish r ep l ica o f t he G oks tad s h ip . Dan ish T our is t Board.
F ig. 1 8.5
T he Dan ish Na t iona l Museu m 's N or land O t tr ing .
" dugou t" ( A tk inson , 1 960 : 1 13-4 ) ; s econd ly t he b u i ld ing o f at arred c anvas c urragh a nd i t s t r ia l c rossing o f t he I r ish S ea i n t he 1 960s ; a nd more r ecen t ly h e worked w i th P ro fessor Marstrander o n h is B ronze Age s k in b oa t e xper imen t ( Johnstone , 1 972 ; Mars trander , 1 976 ) .
An o t s o we l l p ub l ic ised r ep l ica i s t ha t o f t he N yda m b oa t s hown i n F ig . 1 8.1 ( Äker lund , 1 963 :45-7 ).
Pau l J ohnstone n oted i n as u m mary o f h is p ro-
j ec ted p aper t ha t t h is was t he f irst b oa t r ep l ica t r ia l t o b e r ecorded i n f i lm a nd h e w ondered whether t h is f i lm c ou ld n ow b e t raced. Ab e t ter k nown r ep l ica i s V ik ing , C ap ta in Magnus Andersen 's 1 893 r epl i ca o f t he Gokstad s h ip , ( F ig . 1 8.2 ) wh ich h e s a iled f ro m Bergen t o N ew foundl and i n 2 8 d ays ( Andersen , 1 895 ) .
V ik ing was b u i l t a s c lose t o t he o r ig ina l
f or m a s p ossib le , w i th t he r ibs l ashed t o c lea ts o n t he p lank ing , a nd t here fore Andersen 's a ccoun t o f h er v oyage i s o f g rea t i mpor tance f or t he u nders tand ing o f t he s ea wor th iness a nd t he s ea k eep ing q ua l i t ies o f t h is f or m o f h u l l .
Bu t
t here a re d oub ts a bou t wha t c an b e l earned f ro m h er p er for mance u nder s a i l . H er s quare ma insa i l was s im i lar i n s hape a nd ma ter ia l t o t hose u sed i n l a te 1 9 th c en tury N orway : t ha t i s i t was made o f h e mp o r f lax , a nd o f h igh a spec t r a t io , t a l l a nd n arrow . C hr istensen ( 1968 : 3 9 ) c onsiders h owever , t ha t V ik ing Age s a i ls were p robab ly t w ice a s w ide a s t hey were t a l l , t ha t i s o f l ow a spec t r a t io , a nd t he c onsensus o f o p in ion i s t ha t t hey were made o f wad ma l
ac oarse woo l len c lo th , p ossib ly s treng thened b y s tr ips o f l inen o r
l eather ( Haasu m , 1 974 :113 ). Fur ther more , V ik ing s o met i mes c arr ied a t ops a il , a nd s o met i mes a f oresa il ( F ig . 1 8.3 ). Thus g reat c are mus t b e t aken i n d raw ing a ny c onc lusions a bou t t he s a i l ing c apab i l i t ies o f V ik ing Age s h ips f ro m t h is r ep l ica 's p er for mance . Ano ther r ep l ica o f t he G oks tad s h ip , Hug in , ( F ig . 1 8.4 ) was b u i l t i n 1 949 a nd s a i led f ro m Den mark t o K en t ( RO je l , 1 949 ).
The Eng l ish l anguage a ccoun t
o f t h is r ep l ica d oes n o t g ive s u f f ic ien t i n for ma t ion f or u s t o j udge h er v a lue a s a n a rchaeo log ica l e xper i men t , a l though o ne i n terest ing f ac t i s r ecorded : 2 0 th c en tury D anes , 2 me tres t a l l , c ou ld n o t e as i ly r ow i n t he s pace b e tween a d jacen t r owing s ta t ions .
One may c onc lude f ro m t h is t ha t V ik ing Age
o ars men were n o t a s t a l l a s t he ir 2 0 th c en tury d escenden ts , o r t ha t r owing s ty les h ave c hanged .
T he r e ma ins o f t h is r ep l ica c an s t i l l b e s een o n t he
b each a t P egwe l l B ay , Ken t . T here h as r ecen t ly b een i ncreasing Dan ish i n terest i n b u i lding b oa t r ep l icas : Egon H ansen ( 1974 ) h as r ecorded s ix b u i l t s ince 1 963 .
A par t f ro m
t hree n o tes b y C rum l in-Pedersen ( 1966 : 2 56-8 ; 1 969 ; 1 970 :9 , 1 8 ) d escr ib ing a spec ts o f t he Im me Gra m me r ep l ica o f t he L adby s h ip , t here i s n o r ead i ly a ccessib le p ub l ica t ion g iv ing d e ta i ls o f t hese e xper i men ts.
C ru m l in-Pedersen
( 1975 : 1 30 ) h as s ta ted t ha t t hese r ep l icas h ave n o t " been r igged a nd s a i led p roper ly , n or h ave t hey b een s ub jec ted t o s er ious t r ia ls" .
N ever the less i t
wou ld b e o f g rea t v a lue i fh e c ou ld g ive a n a u thor i ta t ive s um mary o f p ast S cand inav ian e xper ience w i th b oa t r ep l icas s o t ha t f u ture r esearch workers c an l earn f ro m i t .
P ossib ly t he f or thco m ing r epor t o n h is c urren t work
e va lua t ing t he p rob le ms o f s a i l ing a N or land O t tr ing ( F ig. 1 8.5 ) w ith a s ing le s quare s a i l , c ou ld b eco me t he o ccasion f or a c o mprehensive p aper .
2 49
A 5
THE GREEN W ICH FAER ING REPL ICA T he N a t iona l Mar i t i me Museu m 's d irec t e xper ience o f e xper i men ta l b oa t a rchaeo logy i s l im i ted t o t he b u i ld ing a nd t r ia ls o f ar ep l ica o f t he f aer ing f ro m G okstad ( F igs. 1 8.6 ,10 ,11 ). Th is was n o t a n i dea l e xper i men t ( McGra i l , 1 975A : 5 ) , b u t we l earned much f ro m i t , a nd g a ined v a luab le e xper ience i n t he t heory a nd p rac t ice o f r ep l ica b u i lding .
A s w i th t he 1 893 Goks tad r ep l ica ,
t here a re p rob le ms i n a t te mp t ing t o u se o ur e xper i men ta l r esu l ts t o d raw c onc lus ions a bou t V ik ing Age s ea mansh ip .
S o me o f t hese d i f f icu l t ies h ave b een
c ons idered e lsewhere ( McGra i l , 1 974 : 3 4 ) , b u t Iwou ld l ike t o d iscuss f ur ther a spec ts h ere , t o i l lustra te s o me o f t he p rob le ms i nheren t i n b oa t r ep l ica work . F ig . 1 8.7 s hows t he f orward i nc l ined f ra me f i t ted t o t he Greenw ich f aer inK , w i th t wo h o les p ierc ing i t . T he d i mensions o f t hese h o les h ad b een s ca led u p f ro m Chr istensen 's 1 :10 d raw ing ( F ig . 1 8.6 ) a nd t he ir l onges t d i mens ion was c . 6 cm t ha t i s , a bou t t hree f ingers b read th .
The f unc t ion o f t hese h o les was
n ot c lear t o u s u n t i l w e o pera ted t he b oa t f ro m t he b each , when i tb eca me n at ura l t o a t te mp t t o u se t he m a s h andho les when h au l ing t he b oa t i n to a nd o ut o f t he wa ter .
I naccura te s ca l ing mean t t ha t t hey w ere i n f ac t t oo sma l l , a l-
t hough t hose o n t he o r ig ina l f aer ing i n Os lo c ou ld b e s o u sed.
When b u ild ing
h is f aer ing r ep l ica , Egon Hansen o f t he Preh istor ic Museu m , Moesgärd , Aarhus , Den mark o bv ious ly a pprec ia ted t h is u se ( F ig . 1 8.8 ), a lthough h is h andho les a re s o mewha t b igger t han t hose o n t he o r ig ina l f aer ing . Chr istensen 's c ons truc t ion p lan f or t he f aer ing ( F ig . 1 8.6 ) s hows a n o ar , r econstructed f ro m a f rag men t , wh ich i s c . 3 .29 m ( 10 f t .9 in .) l ong. I t i s n ow n ex t t o imposs ib le t o s ay wh ich o f t he f rag men ted o ar r e ma ins b e longed t o wh ich b oat , a nd i t may b e t ha t Chr istensen b ased h is d raw ing o n f ragmen ts f ro m t he l arger , 6 -oared b oa ts , a lso f ound i n t he G okstad s h ip ( Chr is tensen , p ersona l c o m mun ica t ion ) . I n s ta t ic t r ia ls a t G reenw ich a n o ar o f t h is l eng th s ee med t o b e t oo l ong f or t he f aer ing , a nd H aro ld K i mber , t he master b oa tb u i lder i n c harge o f b u i ld ing t he G reenwich r ep l ica , made t wo o ars o f l eng th c2 .52 m ( 8 f t . 3 in .) , c a lcu la ted a s t w ice t he b ea m o f t he b oa t a t t he t ho les. T h is p a ir was u sed i n t he r owing t r ia ls t oge ther w i th 2 0 th c en tury p a irs o f o ars o f 2 .46 m a nd 3 .05 m l eng th ( McKee , 1 974 : 1 8 ) .
I n r e trospec t , i t migh t
h ave b een w iser a nd more i n k eeping w i th e xper i men ta l me thods f or u s t o h ave d one more r esearch i n t he B ygdOy a rch ives b e fore b u i ld ing t he r ep l ica , o r t o h ave u sed a p a ir o f 3 .29 m l ong o ars , a nd a t te mp ted t o f ind a r owing t echn ique a nd a n o pera t ing e nv iron men t s u i tab le t o t he m .
T he f ac t t ha t we a lso e xper i-
e nced d i f f icu l t ies d ur ing o ur t r ia ls when u sing 2 0 th c en tury r owing me thods i n t he s ee m ing ly i nadequa te d istance b e tween t he t hwar ts ( .95 m = 3 f t . 1 1-i n .) , emphasises t he l a t ter p o in t . McKee ( 1974 : 1 3-17 ) h as d escr ibed s o me o f t he p rob le ms e ncoun tered i n e va lua t ing t he s teer ing a rrange men ts o f t he f aer ing .
I t may n o t h ave b een
s u f f ic ien t ly emphasised h owever t ha t t he e f fec t iveness o f t he s ide r udder p roba b ly d epends t o a marked d egree o n t he s hape o f t he r udder b oss ( F ig . 1 8.9 ), a nd t he f i t o f t he r udder t o t ha t b oss.
T here a re o bv iously g rea t d i f f icu l t ies
i n g e t ting t he p recise t hree d i mensiona l s hape f ro m C hr istensen '6 d raw ings , a s c an b e s een b y c o mpar ing t he Greenwich b oss ( F ig . 1 8.9 ) w ith t he d raw ing ( F ig .18.6 ).Fur ther more , a t t he t ime o f t he Greenw ich e xper i men t i t was n o t 2 51
F ig . 1 8.7
ward i nc l ined f ra me o f t he
T he f ore s te m a nd t he f or-
A s im ilar v iew o f t he _ f ae _ r ing r ep l ica b u ilt b y Egon
G reenw ich f aer ing r ep l ica.
Hansen a t Moesg4rd.
Na t iona l Mar it i me Museu m.
N a t iona l Mar it i me Museu m .
F ig . 1 8.9
F ig . 1 8.8
The r udder b oss o n t he Greenw ich f aer ing r ep l ica. Na t iona l Mar it i me Museu m .
F ig . 1 8.10 T he G reenw ich f aer ing r ep l ica u nder o ars. Na t iona l Mar it i me Museu m.
F ig . 1 8.11 T he Greenw ich f aer ing r ep l ica u nder s a il. Bas i l Greenh il l.
a pprec ia ted t ha t t he i nboard s ur face o f t he o r ig ina l r udder may h ave b een d ished t o ma tch t he s hape o f t he b oss.
T he s urv iv ing e v idence i s n o t u n-
amb iguous a nd t he d epression o n t he i nside o f t he f aer ing r udder may b e d ue t o wear i n u se o r p ressure d a mage i n t he g round ( Chr istensen , p ersona l c o m mun ica t ion ) , b u t i ft he d epression i s i n ten t iona l i t wou ld e f fec t t he r udder e f f iciency .
I n a dd i t ion , we d id n o t p ersist i n o ur a t te mp ts t o f ind t he b est
me thod o f b ind ing t he r udder b y w i thy t hongs t hrough t he b oss t o t he a f t i nc l ined f ra me ( McKee , 1 974 : 1 4 ) , b u t u sed h e mp r ope f or t he r ecorded t r ia ls. Wi th t hese d oub ts a nd d iscrepanc ies i ti s n o t p ossib le t o d raw c onc lusions f ro m t he Greenw ich e xper i men t a bou t t he e f f ic iency o f t he o r ig ina l f aer ing 's s teer ing g ear .
N or n eed we y e t c onsider McKee 's t en ta t ive h ypo thesis
( 1974 : 2 6 ) , t ha t s ince t he s teer ing g ear o f t he G reenw ich f aer ing i s o n ly e f fec t ive f or sma l l a ng les o f h e lm , t h is may h ave b een ' a s ign i f ican t o bs tac le t o t he d eve lop men t ' i n V ik ing t imes ' o f as a i l ing b oa t t ha t c ou ld c hange t acks '. More r esearch a nd e xper i men ta l work a re r equ ired . LONG TER M USES OF BOAT REPL ICAS Dur ing 1 975 a nd 1 976 E r ic McKee s a i led t he f aer ing r ep l ica w i th a s ing le s quare s a i l ( F ig .18.11 ) t o g a in s o me u nders tand ing o f t he p rob le ms o f h and l ing a sma l l b oa t w i th t h is t ype o f r ig .
Fur ther t r ia ls i n t he S pr ing o f 1 977 w i l l
b e t he f ina l o nes i n t he f i rst s er ies. p roduc t ive? o ther e f fec ts.
Wou ld a f ur ther s er ies o f t r ia ls b e
We a re p lann ing l onger t er m t r ia ls t o a ssess wear i n u se a nd Bu t i s t here more we c an g e t f ro m r ep l icas s uch a s t h is o ne ,
wh ich r epresen t ah eavy i nvest men t?
T i me a nd money may b e j usti f ied b y
t he k now ledge g a ined d ur ing t he b u i ld ing a nd t he t r ia ls.
We may a lso g a in
a n a dd i t iona l r e turn b y u sing t he r ep l ica a s at est v eh ic le t o l earn t he a r t o f s a i ling w i th a s ing le s quare s a i l ; o r t o e va lua te a p ro to type t r ia ls p rogra m me ; o r t o a c t a s ac on tro l b y p rov id ing f eedback t o t heore t ica l mode ls u sed i n t he n ava l a rch i tec tura l e va lua t ions . u se fu l r igh t t o t he e nd o f h er l i fe?
Bu t c an a b oa t r ep l ica b e a rchaeo log ica l ly Ih ave e lsewhere s uggested ( McGra i l ,
1 974 : 3 7) -p ossib ly l igh thear ted ly - t ha t t he f aer ing r ep l ica migh t b e i n terred i n ab ur ia l mound t o b e e xcava ted i n f uture y ears o n t he l i nes ,o f t he e xper imen ta l e ar th works a t Over ton D own ( Jewe l l a nd D i mb leby , 1 966) a nd Wareha m ( Evans a nd L i mbrey , 1 974 ) .
T here wou ld b e p rob le ms o f f inance
a nd l og ist ics , o f c on tinu i ty a nd r epea tab i l i ty -b u t i s t h is s uggest ion wor th c onsider ing s er iously? Wou ld b oa t a rchaeo log ists a nd o thers g a in s u f f ic ien t t o j us t i fy t he e f for t? I fn o t , a re t here b e t ter ways o f u sing a b oa t r ep l ica i n t he l ong t er m , t o t he g rea ter g a in o f Archaeo logy?
Ib e l ieve t hat q ues t ions
s uch a s t hese s hou ld b e a sked a s p ar t o f t he c os t/bene f i t a na lysis t ha t must p recede a ny d ec is ion t o b u i ld a b oa t r ep l ica . THE PR INC IPLES AND METHODS OF EXPER I MENTAL BOAT ARCHAEOLOGY The t heory o f a rchaeo log ica l e xper i men ts e xpounded b y J ohn C o les i n t he p reded ing p aper g enera l ly a pp l ies t o b oa t r ep l icas.
E lsewhere ( 1975A ) I
h ave d iscussed p rocedures wh ich may e nsure max i mu m a rchaeo log ica l v a lue f ro m a b oa t r ep l ica e xper i men t .
T hese i nc lude t he c ho ice o f a wor thwh i le
s ub jec t f or t he e xper i men t ; t he s e lec t ion o f t he p ro jec t t ea m ; t he c ho ice o f t he
2 54
e nv iron men ta l c ond i t ions f or b u i ld ing a nd t esting t he r ep l ica ; t he c ho ice o f t oo ls a nd o f c onstruc t iona l me thods a nd t he way t o " trans la te" t he o r ig ina l i n to a r ep l ica ; t he d esign o f at r ia ls p rogra m me ; a nd f i na l ly t he n ecessi ty t o r ecord t he e xper i men t i n d e ta i l , i nc luding t he r eason ing b eh ind d ecisions t o a dop t o r r e jec t p ar t icu lar c ourses o f a c t ion , s o t ha t o thers c an a ssess t he v a lid i ty o f t he e xper i men t . S ince 1 974 t he Na t iona l Mar i t i me Museum h as b een p lann ing t he b u i ld ing o f ar ep l ica o f t he G raveney B oa t , a mid 1 0 th c en tury A .D . c argo b oa t whose f ragmen tary r e ma ins were e xcava ted b y t he N a t iona l Mar i t i me Museum a nd t he B r i t ish Museu m i n 1 970 ( Fenw ick , f or thco m ing ) . T h is p re l im inary p lann ing h as l ed me t o b e l ieve t ha t g rea ter emphasis s hou ld b e p laced o n t he e ar ly s tages o f a n e xper imen t .
I n g enera l t here w i l l b e s evera l p ossib le
s o lu t ions t o t he p rob le m o f h ypo the t ica l ly r econs truc t ing t he f u l l o r ig ina l f or m o f a n i nco mp le te b oa t f ind : s o me o f t hese s o lu t ions may v ary o n ly b ec ause o f minor d i f ferences i nf i t t ings a nd " tr im m ings" , b u t o thers may h ave s ign if ican t ly d i f feren t h ydrosta t ic a nd h ydrodyna m ic c harac ter ist ics , a nd o pera t iona l c apab i l i t ies .
Ib e l ieve t ha t t hese v ar ian ts s hou ld b e t horough ly
i nvest iga ted i n av ar ie ty o f ways b e fore a d ec ision i s t aken wh ich v ersion t he r ep l ica b u i lder i s t o u se i n h is p rac t ica l e xper i men t . T hus, b y sma l l s ca le mode l b u i lding , b y n ava l a rch i tec tura l c a lcu la t ions a nd t he p lo t t ing o f h ydros ta t ic c urves , b y c o mpu ter s i mula t ion , a nd b y t ank t ests , t hese t heore t ica l a l terna t ives c an b e e va lua ted f or p rac t icab i l i ty o f b u i ld ing , f or s tabi l i ty a nd l oad c arry ing e f fec t iveness , a nd f or p er for mance w i th d i f feren t me thods o f p ropu lsion u nder a r ange o f o pera t iona l a nd e nv ironmen ta l c ond i t ions . T hese a re e xper i men ts wh ich c an b e r epea ted u sing many d i f feren t v a lues o f t he p ara me ters , a nd t hey c an b e r epea ted b y o thers . T hese t heore t ica l mode ls c an b e ' d is man t led ' a nd ' rebu i l t ' many t imes b e fore we n eed c rysta l l ise o ur i deas o n t he v ersion t o b e b u i l t a s af u l l s ize r ep l ica , wh ich w i l l h ave o n ly l im i ted a dap tab i l i ty o nce i t s ma in d esign p ara me ters a re e s tab l ished . Much s hou ld b e l earned d ur ing t hese t heore t ica l e va lua t ions : n ega t ive f i nd ings a nd t he r e jec t ion o f h ypo theses c an g ive v a luab le i nsigh t , o f ten a s v a luab le a s p osi t ive i n for ma t ion ; i nconsistanc ies i n r eason ing may b e h igh l igh ted a nd d irec t ives r e for mu la ted a ccord ing ly ; a nd t he c r i ter ia b y wh ich t o c hoose a p re ferred s o lu t ion s hou ld b e c lar i f ied .
I n c er ta in c ases t h is f or m o f a na lysis
may s how t ha t i ti s n o t y e t t he t ime t o p roceed t o t he f u l l s ize r ep l ica p hase -t he d ecision p ossib ly b e ing d e ferred u n t i l more e v idence b eco mes a va i lab le . T here must h owever b e c on tro ls f or t hese t heore t ica l i nvest iga t ions , a nd i ndeed a s J ohn Coates p o in ts o u t ( Th is v o lu me p . 2 26 ) n ava l a rch itec ts p refer t o h ave p ract ica l c on f irma t ion o f c a lcu la ted a ssess men ts , e spec ia l ly t hose o f s peed a nd o f s a i ling p er for mance . T here s hou ld b e f eedback t o t heore t ica l mode ls f ro m b o th t he b u i ld ing a nd t he t r ia ls p hases o f ab oa t r ep l ica e xper i men t , e nab l ing t he t heore t ica l mode ls t o b e amended , f or e xa mp le , b y t he a dd i t ion o f n ew v ar iab les whose e x is tence was n o t s uspec ted u n t i l t he p rac t ica l work r evea led t he m .
T he f i rst b oa t r ep l ica i nvest iga ted b y t hese me thods w i l l
u ndoub ted ly t ake l onger t o b u i ld t han a n t ic ipa ted , a nd t here w i l l b e much d iscussion wh i lst t he t heoret ica l a nd p rac t ica l a spec ts a re s ynchron ised a nd made c onsistan t , b u t f u ture e xper i men ts s hou ld b ene f i t f ro m t he r e f ined a na ly t ica l t echn iques wh ich emerge .
2 55
H aasu m ( 1974 ) , h as u sed s o me o f t he i n terdiscip l inary t echn iques Ih ave d escr ibed a bove i n at heore t ica l i nves tiga t ion o f V ik ing s h ips u nder s a i l . work h as b een c r i t ic ised b y C ru m l in-Pedersen ( 1975 : u ncr i t ica l u se o f s ources a nd me thods .
H er
1 30 ) b ecause o f h er
Wh i ls t a gree ing t ha t t h is c r i t ic is m
may b e we l l f ounded , Iwou ld n ever the less a pp laud H aasu m f or h er p ioneer ing s p ir i t i n a t te mp ting t o u se h ydrodyna m ic a nd a erodyna m ic a na lys is t o g a in i ns igh t i n to t he p ossible c apab i l i t ies o f s h ips o f t he V ik ing Age .
T here i s ap lace
f or t h is t ype o f t heore t ica l a ssess men t i n a ny s tudy o f a n a nc ien t b oa t , p rov id ing t ha t t he d a ta i s s ound .
A dd i t iona l ly , t here i s ar equ ire men t t o v a l ida te
t he t heore t ica l mode l b y p rac t ica l t r ia ls , b u t t h is may h ave b een b eyond t he r esources a va i lab le t o H aasu m . T he N a t iona l Mar i t i me Museu m w i l l p robab ly u se t h is i n ter med ia te s tage o f t heore t ica l mode l b u i ld ing t o i nvest iga te n o t o n ly t he Graveney b oa t b u t a lso t he Br igg ' Ra f t ' ( McGra i l , 1 975b ) a nd t he K en t mere b oa t ( W i lson , 1 966 ) . E .V . Wr igh t a nd J ohn C oa tes a re n ow e va lua t ing s evera l a l terna t ive h ypo the t ica l r er econstruc t ions o f F err iby b oa t 1 , ( Wr igh t , 1 976 ) a nd i ti s c once ivab le t ha t t hey t oo may u se t hese t heore t ica l p rocedures t o e xp lore t he ir r econstruc t ions. Ib e l ieve t ha t t ime s pen t o n t h is s tage o f a ny r esearch p rogra m me w i l l b e o f t re mendous b enef i t n o t o n ly b ecause o f t he k now ledge i m med ia te ly g a ined , b u t a lso i n t he u l t i ma te v a lue o f t he f u l l s ize r ep l ica , s hou ld i tb e d ec ided t o b u i ld o ne . A cknow ledge men t
Iam g ra te fu l t o Arne Em i l C hr is tensen f or d iscussions o n a spec ts o f t h is p aper .
2 56
REFERENCES Andersen , M., 1 895 .
• V ik inge faerden , Kr ist ian ia .
A tk inson , R .J .C ., 1 960 . S tonehenge , L ondon . 0 N yda mskeppen , G o teborg . Aker lund , H ., 1 963. C hr is tensen , A .E ., 1 968 .
B oa ts o f t he N or th , O s lo .
C rum l in-Pedersen , 0 ., 1 966 . M irror , 5 2 :
' Two Dan ish S ide R udders ' Mar iner 's
2 51-261 .
C ru m l in -Pedersen , 0 ., 1 969 .
' Kopi a f e t V ik ingesk ib ' S ka lk 1 969 ( 2 ) :
2 6-
2 7. C rum l in-Pedersen , 0 ., 1 970 .
' V ik ing S h ips o f R osk i lde ' i n N a t iona l Mar i-
t ime Museum Monograph N o . 1A spec ts o f t he H is tory o f Wooden S h ipb u i lding :
7 -23 , G reenw ich .
C rum l in-Pedersen , 0 ., 1 975 . Mirror 6 1 :
' V ik ing S ea mansh ip Ques t ioned ' Mar iner 's
1 27-131 .
Evans , J .G ., a nd L irnbrey , S ., 1 974 .
' Exper i men ta l E ar thwork o n Morden
B og ', Wareha m , D orse t , Eng land : h istor ic S oc ie ty , 4 0 : Eve i l lard , E ., n .d .
1 9631972 ' P roceedings o f t he P re-
1 70-202 .
' Nav iga t ion d e p la isance ' f asc ic le N o . 7 0 i n L acroix ,
E . ( ed ) N ouve l le t echno log ie d es a r ts e t me t iers V o lu me 4 , t o me 7 . P ar is . Farr , G ., 1 976.
S h ipbu i lding i n N or th D evon , N a t iona l Mar i t i me Museu m
Monograph N o. 2 2 , G reenw ich . F enwick , V .H ., ( ed ) , f or thco m ing . Haasum , S ., 1 974 .
G raveney B oa t .
V ik inga t idens S eg l ing o ch N av iga t ion , U n iversi ty o f
S tockho lm , T heses a nd P apers i n N or th European Archaeo logy 4 . S tockho lm . Hansen , E .H ., 1 974 .
U npub l ished p aper o n a rchaeo log ica l r ep l ica b u i ld ing .
Moesgaird . Hass lö f , 0 ., 1 972.
' Concep t o f L iv ing T rad i t ion ' i n H asslö f , 0 ., e t . a l
( e d ) S h ips a nd S h ipyards , S a i lors a nd F isher men : , J ewe l l , P .A ., a nd D i mb leby , G . W . ( ed ) , 1 966 . o n Over ton D own , Wi l tsh ire , Eng land : c eed ings o f t he Preh is tor ic S oc ie ty , 3 2 : J ohnstone , P ., 1 972 . McGra i l , S ., 1 974 . G okstad f aer ing .
2 0-26 , C openhagen .
' Exper i men ta l E ar thwork
t he f irs t f our y ears.'
P ro-
3 13-42 .
' Bronze Age s ea t r ia l ' An t iqu i ty , 4 6 :
2 69-274.
Bu i ld ing a nd t r ia ls o f ar ep l ica o f a n a ncien t b oa t : P ar t 1 .
t he
N a t iona l Mar i t i me Museu m Monograph N o .
1 1. Greenwich . 2 57
McGra i l , S ., 1 975A .
' Mode ls , Rep licas a nd Exper i men ts i n N au t ica l Arch-
a eo logy ' Mar iner 's Mirror , 6 1: McGra i l , S ., 1 975B .
' Br igg Raf t r e-excavated ' L inco lnsh ire H istory a nd
Archaeology , 1 0 : McKee , E ., 1 974.
3 -8 .
5 -13.
Bu i lding a nd t r ia ls o f ar ep lica o f a n a ncien t b oa t :
Gokstad f aering .
t he
Par t 2 , Na t iona l Mar i t i me Museu m Monograph No . 1 1 ,
Greenwich . Marstrander , S ., 1 976.
' Bu i ld ing a h ide b oa t .
An a rchaeo log ica l e xper i-
men t ' I n terna tiona l J ourna l o f Nau t ica l A rchaeo logy , 5 : R 9 S jel , J ., 1 949.
1 949 , C ru ise o f t he V ik ing S h ip Hug in .
Wi lson , D . M., 1 966.
C openhagen .
' Med ieva l b oa t f ro m Ken t mere , West mor land '
Med ieva l Archaeo logy , 1 0 : Wr igh t , E . V., 1 976.
1 3-22 .
8 1-88 .
Nor th Ferr iby B oa ts , Na t iona l Mar i t i me Museum
Monograph N o. 2 3 , Greenw ich .
2 58
1 9.
PREL IM INARY REPORT ON THE BRENDAN PROJECT
T i mothy S ever in S u m mary
A3 6f t . s k in b oa t r ep l ica h as b een b u i l t o f t he Wes t I r ish t ype a t tr ibu ted t o t he l a te 5 th c en tury A .D .
T he d esig n . was b ased o n s urv iv ing I r ish
c urraghs a nd l i terary r e ferences.
R esearch was c onduc ted i n to t he
p roper t ies o f o ak-bark t anned l ea ther f or t he h u l l s k in , o n a n o ak a nd a sh f ra me l ashed w i th l ea ther t hongs. s heep woo l .
L ea ther d ressing was g rease f ro m
S ea t r ia ls i nd ica te n i l w indward p er for mance , 2 -3 k no ts
c ru ising s peed , b u t c onsiderab le s tab i l i ty a nd s eawor th iness.
On p as-
s age f ro m Wes t I re land t o I ce land t here was n o a pprec iab le d egrada t ion o f t he l ea ther s k in .
T he p ro jec t c on t inues .
T he ma in p urpose o f t he Brendan Voyage , wh ich i s s t i l l u n f in ished , i s t o l earn b y p rac t ica l t r ial whe ther a l arge s k in b oa t o f t he t ype wh ich may h ave b een i n u se i n t he wes t o f I re land b e tween t he 5 th a nd 9 th c en tur ies A .D ., c an s urv ive a ma jor o cean p assage .
I n p ar t icu lar i ti s h oped t o l earn whe ther
s uch a b oa t c ou ld f o l low t he ' s tepp ing s tone ' r ou te b y way o f t he Hebr ides , Faeroes a nd I ce land t o G reen land a nd N or th Amer ica wh ich h as b een p ostu la ted b y an umber o f s cho lars.
I fs o , Ib e l ieve t ha t f irst-hand k now ledge o f t h is
r ou te i s c on ta ined w i thin t he N av iga t io o f S t . B rendan , t o a bou t 8 00
1
aL a t in t ex t n ow d a ted
A .D . wh ich s ee ms t o d escr ibe t he g eography o f t h is p ar t o f t he
N or th A t lan t ic . T he me thod o f t he p ro jec t h as b een t o f ind o u t a s much a s p oss ib le a bou t t he t ype o f s k in v esse l wh ich was i n u se a t t he t ime , b u i ld a s c lose a r ep l ica a s t he f ac ts wou ld a l low , a nd t hen a t te mp t t o n av iga te t he c ra f t a long t he s a me r ou te . T he p r i mary h istor ica l s ource f or t he c onstruc t ion o f t he r ep l ica s k in b oa t was t he t ex t o f t he N av iga t io i t se l f .
T hough t erse , t he N av iga t io i s c lear a bou t
t he manner o f b oa tbu i lding , t he t ype o f l ea ther wh ich i s s ta ted t o b e a n o ak b ark t anned l ea ther , a nd t he u se o f s o me s or t o f b u t ter o r f a t t o d ress t he l ea ther . I t was p ossib le t o c ross-check s o me o f t hese d eta ils w ith r eference t o o ther e ar ly C hr ist ian t ex ts wh ich men t ion t he s k in b oa ts u sed b y I r ish monkn av iga tors , a nd a lso t o g lean s o me c lues a s t o s ize , r ig , a nd s h ip h and l ing . I n p ract ica l t er ms t he e thnograph ic e v idence d er ived f ro m t he s k in b oa t d escendan ts i n t he west o f I re land was i nva luab le i n l ay ing d own t he g u ide l ines f or d es ign a nd c ons truct ion o f t he r ep l ica .
T he s k in b oa t d escendan t o f t he
west o f I re land i s , o f c ourse , t he c urragh ;
a nd i ti s p erhaps s ign i f ican t t ha t
t he most e legan t a nd s eawor thy o f t he v ar ious I r ish c urragh d esigns , a s H orne 1 12
2 59
p o in ted o u t , i s t he c urragh o f t he D ing le p en insu la i n C oun ty Kerry , a sma l l a rea wh ich i s a lso t he h o me o f S t . B rendan a nd t he p lace f ro m wh ich h e i s s a id t o h ave embarked o n h is westward v oyage . C lear ly t he i n i t ia l s tep t owards d ec iding t ob u i ld a r ep l ica was t o c heck t he p o ten t ia l s eawor th iness o f as urv iv ing c urragh . T hese b oa ts a re s t i l l i n u se i n t he D ing le , t hough t he ir n umbers a re d ecreasing r ap id ly . P erhaps 4 0 o f t he m a re s t i l l i n r egu lar u se , most w i th a n o u tboard mo tor ' b ox ' t o r ep lace t he mast a nd s a i l wh ich i s n o l onger u sed o n t he work ing b oa ts when l obster f i sh ing . T hey d o , h owever , c on form i n s ize , d es ign a nd c onstruc tion t o t he D ing le c urraghs wh ich H orne l l d escr ibed . T here i s o n ly o ne f u l lt i me c urragh maker s urv iv ing , J ohn G odw in o f Maharees ; a nd t o l earn s o me th ing o f h is t echn iques t he a u thor o rdered t he sma l lest c urragh - k nown l oca l ly a s t he ' two h and p un t ' -a nd a ss is ted w i th i t s c overing w i th t he h o t t arred c anvas c oa t t ha t n ow r ep laces t he l ea ther s k in . T he c o mp le ted t wo h and c urragh t hen s erved a s au se fu l t es t b ed f or p ract ica l e xper i men ts , r igg ing a nd s a il ing t hese b oats. Add i t iona l i n for ma t ion a bou t c on te mporary ma ter ia ls a nd t echn ica l s k i l l was o bta ined b y e xa m in ing o ther e ar ly Chr is t ian a r t ifacts. The a va i lab le t ypes o f wood , f or e xamp le , c ou ld b e d e term ined f rom e ar l ier work o n c harcoa l a na lys is o f h ear th f ires , a nd most i mpor tan t o f a l l i t was p oss ib le t o e xam ine c on te mporary I r ish l ea therwork i n t he f orm o f t he b ook s a tche ls o r b udgets , s ome o f t he v ery f ew s urv iv ing e xa mp les o f e ar ly med ieva l l eatherwork a nd d one - c onven ien t ly e nough - i n a ssoc iat ion w ith monas t ic c o m mun it ies.
3
T he most f ru i t fu l l i ne o f ma ter ia ls r esearch was u ndoub ted ly i n to t he p roper t ies o f o ak b ark l ea ther a s men t ioned i nt he N av iga t io . P ara l le l t o s uch s tra igh t forward t ests a s h ang ing s quares o f t he l ea ther i n t he s ea a nd p er iod ica l ly s ee ing wha t h ad h appened t o t hem , t he l abora tor ies o f t he B r i t ish L ea ther Manu fac turers ' R esearch A ssoc ia t ion v ery k ind ly c arr ied o u t ar es earch p rogra m me , u sing t he s pec ia l ised e qu ip men t a va i lab le t o t he m , i n to t he p roper t ies o f o ak b ark l ea ther t o t ry t o d e term ine i t s s u i tab i l i ty f or t he h u l l me mbrane o f ab oa t . U sing we t a nd d ry s amp les , s a mp les t rea ted w i th d i f feren t d ressings , a nd s a mp les u nder d yna m ic a nd s ta t ic c ond i t ions , t he l abora tor ies c hecked t ensi le s treng th , we igh t , e x tension , a nd i mper meab i l i ty a s we l l a s t he s u i tab i l i ty o f v ar ious f a t ty d ress ings s uch a s c od o i l , t a l low , b u t ter , a nd t he woo l g rease f ro m s heep . T hese t ests were c onduc ted s o t ha t t he o ak b ark l ea ther was ' i n c o mpe t i t ion ' w i th s e lec ted s pec ia l-purpose mode rn l ea thers a s we l l a s w i th r awh ide a nd a lum t annages . T o t he g rea t i n terest o f t he r esearch t ea m - a nd my own g ra t i f ica t ion -t he med ieva l o ak b ark l ea ther p roved f ar s uper ior t o i t s r iva ls a s ah u l l c over . T ens i le s treng th a f ter p ro longed s oak ing , f or e xa mp le , was f ar s tronger t han a ny o ther t ype o f l ea ther . S im i lar t es ts were c onduc ted o n s a i l l ea thers a nd t he l ea ther u sed f or t hongs t o l ash t he wooden f ra me o f t he r ep l ica . On t h is a ccumu la ted e v idence , t hen , C o l in Mud ie t he n ava l a rch i tect p rod uced a d esign s tudy a nd a s e t o f l i nes p lans f or t he c ons truc t ion o f t he r ep l ica v esse l ( F ig . 1 9.1). The s ize o f t he v esse l , n amed Brendan , was a rb itrar ily s e lec ted a t 3 6f t . a s b e ing c onven ien t f or r econs truc t ion a nd a lso s u f f ic ien t t o c on tain t he n u mbers o f p assengers who a re s upposed t o h ave a cco mpan ied S t . B rendan a nd s im i lar v oyagers.
T he b ea m o f t he v esse l was d esigned a t
2 60
F ig . 1 9.1
S che ma t ic d raw ing o f t he o r ig ina l p lanned l ay-ou t o f Brendan . S ubsequen t ly , f ore a nd m idsh ip c ab in s he l ters w ere a dded . T he s teer ing o ar w as s uppor ted o n a n Hf ra me , a nd t he u nstayed mas ts -s hown h ere p ass ing t hrough t he t hwar ts - w ere h e ld b y mas t p ar tners r unn ing f ore a nd a f t a t t hwar t l eve l.
F ig . 1 9.2
The s ke leton o f a1 : 12 s ca le mode l o f Brendan , b u il t b y Ar thur S a luz o f P oo le. T h is w as s ubsequen t ly c overed w ith East I nd ian g oa tsk in .
8 f t .;
h er d ra f t a t a pprox i ma te ly l f t . a nd t he d es igned we igh t f or t he b are h u l l
was a pprox i ma te ly 2 000 l bs. t hough t h is l ast f igures was c onsiderab ly e xceeded i n t he f in ished b oa t . T he n ex t s tage was t o c o mp le te a s ca le mode l ( F ig . 1 9.2 )f ro m Co l in Mud ie 's p lans , f ro m wh ich i t was h oped t o l earn i n a dvance s o me o f t he c onstruc tion d if f icu l t ies t ha t migh t a r ise i n t he f u l l s ca le v esse l .
E ven i n t he mode l i t was
f ound t ha t t he l og ica l way o f b u i ld ing t he b oa t was u pside d own , i .e . l ay ing t he g unwa les f irst , a s i s s t i l l d one b y J ohn G odwin . F or t he i n i t ia l s hap ing o f t he wooden f ra me t he C rosshaven B oa tyard i n C o . C ork was s e lec ted .
T he s h ipwr igh ts were a sked t o f a ir u p a wooden
f ra me t o C o l in Mudie 's d rawings.
T he o n ly t imber t o b e u sed was t imber
a va i lab le i n t he e ar ly C hr is t ian e ra i n I re land - o ak f or t he g unwa les t hwar ts , a sh f or t he f ra mes a nd s tr ingers .
a nd
T o f a ir u p t he h u l l s hape i t was
d ec ided t o p in i tt oge ther l igh t ly w i th o rd inary w ire n a i ls.
A t t h is s tage t he
p ro fessiona l s h ipwr igh ts ' work was f in ished , a nd v o lun teers b egan t o l ash t og e ther t he f ra me , r e mov ing t he w ire n a i ls a s t he work p roceeded .
T he l ea ther
s e lec ted f or t he t hongs was a lu m t anned - a k nown t echn ique i n R o man d ays. T h is l ea ther i n f ac t was u nsu i tab le f or t he h u l l me mbrane , t hough more s tab le u nder s tre tch o nce t he i n i t ia l e las t ic i ty h ad b een t aken o u t ,
C opy ing t he t ech-
n ique o bserved i n t he s urv iv ing l ea ther c urraghs , t he l ea ther t hongs wh ich l ash t oge ther t he b oa t were j oined e nd t o e nd t o p rov ide a c on t inuous s trand a cross e ach f ra me f ro m o ne g unwa le t o t he o ther . I t was f ound t ha t t h is l ash ing t echn ique p roduced a s uf f ic ien t ly s trong h u l l s o t ha t u p t o ad ozen p eop le c ou ld s tand o n t he u pturned f ra me wh i le t hey were work ing .
T o p reserve t he a sh
f ra me f ro m s ea-wa ter a t tack , t he e n t ire s truc ture was c oa ted w i th woo l g rease , wh ich a lso p ro tec ts t he l ea ther . 4 2 o x h ides were e ven tua l ly n eeded t o c over t he h u l l o f Brendan , e ach o ne b e ing f i t ted i nd iv idua l ly i n p lace . T he h ides were o f y oung o xen , a verag ing 4m m i n t h ickness , o r a pprox i ma te ly t he t hickness o f s urv iving e xa mp les o f e ar ly med ieva l l ea ther f ro m I re land 3 . T he h ides were s t i tched t oge ther b y h and , u sing e i ther a b ack s t i tch , o r as add ler 's t wo-hand s t i tch .
T he l a t ter
i nvo lves u sing t wo n eed les , s o t he l abour f orce h ad t o d iv ide i n to p a irs, e ach p erson p assing t he n eed le t hrough t he l ea ther t o h is p ar tner .
H and-ro l led
f lax t hreads o f 1 6-cord t h ickness were u sed t o s t i t ich t he h ides t oge ther .
B y
f ar t he mos t d i f f icu l t a reas were f ound t o b e t he b ow a nd s tern p or t ions o f t he h ide c over ing .
T he o n ly c ra f ts men a va i lab le t o work t h is t ype o f l ea ther
a nd i n s uch t h inkness was a c ar thorse c o l lar maker , whose l ea therwork ing s k i l ls were f ound t o b e e ssen t ia l . S co t t ish c urragh ,
4
A s o n t he s urv iv ing f ragmen t o f a n e ar ly
t he l ea ther h u l l me mbrane was f ina l ly a t tached b y l app ing
o ver t he u pper g unwa le a nd l ash ing d own t o t he s ign i f ican t ly c onven ien t l ower g unwa le . The o ars f or t he Brendan a re o f t he t rad it iona l t ype d escr ibed i n Horne l l a nd s t i l l i n u se .
T hey p ivo t u pon a wooden b u l l a nd s ing le t ho le p in .
U sing
t he h arness maker 's t echn ique i t was f ound t ha t t he s i mp les t f ix ing f or t he s ide s teer ing o ar was a l ea ther s trop . I n i t ia l t ests were c arr ied o u t a t t he C rosshaven B oa tyard , w i th t he s h ipwr igh ts s erv ing a s c rew .
I t was f ound t ha t t he b oa t was d i f f icu l t t o manoeuvre
a nd p ar t icu lar ly s uscep t ib le t o w indage ( F igs. 1 9.3 a nd4 ). Ear ly s a il ing t ests
2 62
F ig . 1 9.3
F ig . 1 9.4
S ea t r ia ls o f Brendan o f f Coun ty Cork , S pr ing 1 976.
T he s tern s teer ing s weep f i t ted t o Brendan , p roved i nef fect ive d ur ing s ea t r ia ls a nd was l a ter d iscarded ; e n larged.
t he s ide r udder was
were d one o n t he l akes o f t he U pper S hannon R iver .
T he b oa t was f ound t o
b e c onsiderab ly more s tab le t han a n t ic ipa ted , a nd t he u nstayed masts were a dequa te , ap rev ious s ource o f s o me worry .
I t was a lso f ound t ha t al arger
s teering o ar was n ecessary , i ft he b oa t was t o b e s teered p roper ly ( t h is may r e la te t o t he s teer ing o ar c arved o n t he B an try B oa t 5) . wh ich was e xpec ted , i s i n f ac t n o t iceab le .
F lex ing o f t he h u l l ,
L eakage t hrough t he l ea ther i s
n eg l ig ib le , e ven t hough t he s ea ms were n e i ther t arred n or p i tched a s h ad p rev ious ly b een t hough t n ecessary . On May 1 7th o f t h is y ear t he Brendan
s e t o u t f ro m B randon C reek w i th
ac rew o f f ive ( and , h app i ly , e scor ted b y t wo D ing le c urraghs f or t he f irs t f ew h undred y ards ) a nd s a i led a io u nd t he west c oast o f I re land , t hrough t he Ou ter H ebr ides a nd t o t he F aeroe I s lands , a nd i n mid-Ju ly r eached R eyk jav ik i n I ce land .
I n g enera l t he wea ther c ond i t ions s he e ncoun tered were r a ther
p oor f or t he t ime o f y ear , a nd t here was p len ty o f s eaway t o t est t he f lex ibi l i ty a nd d urab i l i ty o f t he s truc ture , e xpec ia l ly d ur ing t hree g a les , o ne o f wh ich p rodcued q u i te h eavy s eas o f f t he I r ish c oas t .
I n my o p in ion t he Brendan
was a s eawor thy c raf t u nder a l l t hese c ond i t ions , t hough s he was s low - a c ru ising s peed o f 2 -3 k no ts was a l l t ha t o ne c ou ld ex pec t i n a ny w ind s treng th l ess t han a F orce 4 /5 . Windward p er for mance was n i l , f or wh i le i t was p oss ib le t o p o in t t he b oa t 6 0-70 d egrees o f f t he w ind , t he c onsiderab le l eeway p roduced a n e f fec t ive c ourse o f 9 0 d egrees o f f t he w ind .
On t he o ther h and
t h is c ourse c ou ld b e ma in ta ined i n s urpr ising ly r ough s eas w i thou t f ear o f swa mp ing o r c apsize .
L eeboards - p robab ly a nachron ist ic - were n o t
a s
e f fec t ive a s l eeside r owing , b u t t he c rew o f f ive was t oo sma l l f or e f fec t ive u se o f t he o ars b eyond manouverin .g i n a nd o u t o f h arbours a nd a nchorages. On t he o ther h and , g iven t he s ize o f c rew a t tr ibu ted t o S t . B rendan , Ib e l ieve t ha t ag enu ine ly u se fu l p er for mance o f t he b oa t u nder o ars c ou ld b e e xpec ted . T h is Ih ope t o t es t l a ter . T he l ea ther i t se l f was v ir tua l ly imper meab le .
Much more wa ter e n tered
t he b oa t f ro m r a in ( o f wh ich we h ad a d epressing amoun t ) o r f ro m a n o ccasiona l wave o ver t he s ide , t han e ver p ene tra ted t he l ea ther s k in . I n p laces t he l ea ther s k in d eve loped wr ink les a nd c orruga t ions o ver t he s tr ingers a f ter p rol onged im mersion .
A lso s o me o f t he s heer was l ost , a pparen t ly d ue t o h ogg ing
a f ter b each ing a nd - Ib e l ieve - a f au l t i n c onstruc t ion o f t he wooden f ra me . H owever t he l ea ther i t se l f , when t he b oa t was h au led u p f or i nspec t ion i n I ce land , was f ound t o b e i n e xce l len t c ond i t ion , t hough s cu f fed a nd s cra tched b y c o l l ision w i th f l o tsa m .
E ven t he woo lgrease was most ly i n p os i t ion t hough
s uppor t ing a l igh t g row th o f b arnac les .
I n s um , t h is s k in b oa t a f ter a l most
s ix mon ths a f loa t was s t i l l s ound a nd wa ter t igh t . Brendan
i s n ow h au led u p f or t he w in ter i n I ce land - i t se l f au se fu l p rac-
t ica l e xerc ise -a nd Ih ope t o r elaunch h er a t t he b eg inn ing o f t he n ex t s a i l ing s eason , p robab ly i n l a te May , i n o rder t o a t te mp t t he l ast l eg o f t he p ro jec t , t he v oyage d irec t t o N or th Amer ica .
F or t h is we w i l l n eed f avourab le w inds .
T hus t he p ro jec t c on t inues , b u t i ti s f a ir t o s ta te t ha t a lready Ih ave a g rea t ly i ncreased r espec t f or t he a ccuracy o f t he med ieva l t ex ts we h ave b een d ea l ing w i th ;
a nd Iwou ld s ub m i t t ha t t he l ea ther-covered b oa t s hou ld n ow b e
r egarded a s h av ing a g enu ine o cean-go ing p oten t ia l. h as n o t l e t my c rew o r me d own .
2 64
S o f ar , a t l eas t , Brendan
NOTES 1 .
S e l mer , C ar l ( ed ) Nav iga t io S anc t i B rendan i Abba t is , Un iv o f No tre Da me P ress , Pub lica t ions i n Medieva l S tudies Vo l . XV I , 1 959 i s t he c r i t ica l e d i t ion .
T ransla ted b y Webb J .F . i n L ives o f t he S ain ts , Pengu in
Books, 1 965 ;
o r O ' Meara , J ohn j ., The Voyage o f S ain t Brendan ,
Do l men Press , Dub l in 1 976. 2 .
H orne l l , J a mes ' Curraghs o f I re land ' Mar iner 's Mirror , J an . 1 938 , p . 2 9.
3 .
B reac Moedo ic Budget i n Na tiona l Museu m o f I reland , Dub l in ; B ook o f Ar magh Budge t , Tr in i ty C o l lege , Dubl in ;
J ., " Ir ish Book-Sa tche ls o r Budge ts" Med ieva l A rchaeo logy 1 2 , 4 .
a nd t he
a lso Wa terer , J ohn ( 1968 ).
Fen ton , A lexander " The Curragh i n S co t land" S co t t ish S tud ies , 1 6 , ( 1973 ) p p 6 1-81.
5 .
J ohnstone , Pau l " The Ban try B oa t" An t iqu i ty 3 8 ( 1964 ) p p 2 77-284.
2 65
D ISCUSS ION G ö thche :
Iam o ne o f ag roup o f Dan ish v o lun teers u nder tak ing s a i l ing t r ia ls o f a n 8 0 y ear o ld f i sh ing b oa t f ro m t he n or thern p ar t o f N orway .
T h is t ype o f b oa t h ad a
s quare s a i l u n t i l t he b eg inn ing o f t h is c en tury a nd we a re l earn ing t o u se t h is t ype o f s a i l .
On t ack ing we
r eached a s peed o f a bou t 5 .5 k no ts a nd s o me t i mes we h ave b een t o n ear ly 1 0 k no ts w i th t he w ind f ro m a stern . S he g oes t o a n a ng le o f a bou t 5 0 d egrees t o t he w ind wh ich i s n o t a s g ood a s t he modern f i sh ing b oa t we h ave i n D en mark .
We h ave a lso u sed t he b oa t w i th a t op-
s a i l a s u sed t o b e d one i n N orway . C o les :
I t wou ld b e o f c ons iderab le v a lue i fs uch a b oa t c ou ld b e u sed t o g ive b asic t ra in ing f or p eop le who w ish t o l earn a bou t t hese b oa ts .
McGra i l :
Are t he Danes s t i l l l earn ing a bou t t h is b oa t?
C ru m l in-Pedersen :
T he work d one w i th t h is v esse l i s p repar ing o ur minds f or t he i n terpre ta t ion o f t he a rchaeo log ica l r e ma ins a s we s ee t he m i n t he V ik ing s h ips.
B y t rave l l ing i n
N orway a nd t a lk ing t o t he o ld b oa tbu i lders a nd f i sher men who b u i l t a nd s a i led t hese s h ips we h ave g o t t o k now p rac t ica l ly e very th ing a bou t h ow t h is was d one , t o t he p o in t where we h ave d e ta i led k now ledge o f h and l ing t he b oa t .
Iam n o t s ay ing t ha t t h is s i tua t ion i s t he s a me a s
t ha t o f t he V ik ing s a i lor . Iam s ay ing t ha t we n ow k now t he s i tua t ion a s i t was a round t he t urn o f t he c en tury i n n or thern N orway , a nd t hus we a re much b e t ter s u i ted f or t he j ob o f u nders tanding a nd i n terpre t ing t he V ik ing s a i ls a nd t he b ehav iour o f t he V ik ing s h ips , t han s o meo ne who h as d one o n ly t heore t ica l work . Wa l le :
If ear e xper i men ts w i th r ep l icas may l ead t o wrong c onc lus ions b ecause y ou may b r ing i n t oo much modern k now ledge a nd t here i s ad anger i n u sing t h is t o p rove o ld me thods.
Exper i men ts i n a wa ter t ank wou ld l ead
t o b e t ter r esu l ts b ecause y ou h ave b e t ter means o f measure men t t han when y ou a re s i t t ing i n ay ach t .
I n
ay ach t as a i lor i s i nc l ined t o b e l ieve t ha t h e i s much c loser t o t he w ind t han h e i s . C rum l in-Pedersen :
We h ave e stab lished a t r ia ls a rea i n t he R osk i lde F jord w i th t hree b uoys p laced a t ak nown d istance a par t a nd we h ave c arr ied o u t an umber o f s a i l ing t r ia ls b e tween t hen .
I n d ue t ime t he r esu l ts o f t hese w i l l b e p ub-
l i shed t oge ther w i th a c o mpar ison b e tween t h is v esse l a nd more r ecen t b oa ts mos t ly w i th g a f f r ig .
T h is
N ord land b oa t was a s g ood a t t ack ing a s t he g a f f r iggers . R egard ing t he w ind t unne l ex per i men t wh ich h as b een q uo ted b y S ibe lla H aasu m Wik in .ga t ideus S eg l ing o ch 2 66
N av iga t ion , 1 974 ) , t here i s at endency t o r egard w ind t unne l o r o ther t est r esu l ts f ro m s c ien t i f ic e xper i men ts t o b e t he t ru th i t se l f , b u t i fy ou c arry o u t t he w ind t unn e l t es ts w i th a s a i l y ou h ave t o make s o me a ssump t ions a bou t t he s hape o f t he s a i l , a nd i ft h is s hape i s n o t t he o p t i mu m o ne y ou w i l l g e t ar esu l t wh ich i s d i f feren t f ro m t he o ne y ou g e t b y s a i ling i n t he s ea w i th t he c apa b i l i ty o f a d just ing y our s a i l t o g ive i ta n o p t i mu m s hape :
t ha t i s wha t many g enera t ions o f s a i lors h ave
b een d eve lop ing .
T here fore It h ink i ti s impor tan t f or
u s n o t j ust t o l eave i tt o mode l t ests a nd n o t t o b e u nc r i t ica l a bou t p rac t ica l e xper i men ts b u t t o g o t o t he ma ter ia l w i th a c r i t ica l mind a nd f ind o u t s o me th ing wh ich c an w i thstand c r i t ic is m . McKee :
Wha t Iam t ry ing t o d o w i th t he Greenw ich f aer ing r epl i ca i s l earn h ow t o s a i l h er a nd a t t he s a me t ime t o e vo lve a way o f c o mpar ing d i f feren t b oa ts.
Ih ave l earn t
q u i te a l o t a bou t s a i l ing a r ep l ica sma l l b oa t .
I tw i l l
b e s o me t i me b e fore Ic an p ub l ish a ny th ing b ecause o ne i s l i tera l ly i n t he s tage o f d esign ing t he e xper i men t b u t Ih ave f ound o u t o ne t h ing wh ich may b e o f i n terest . L ast s u m mer Iwas s a i l ing w i th a r ec tangu lar s a i l made o f av ery s o f t ma teria l , a nd Imanaged t o g e t t h is much sma l ler b oa t t han t he N ord lander s a i l ing r a ther b e t ter t han a b road r each . T h is s um mer Ih ave h ad a s a i l wh ich w i l l s tand v ery much c loser t o t he w ind , b u t t he b oa t i t se lf d oesn 't g o s o we l l t o w indward w i th t h is mode rn s a i l .
It h ink a l o t o f t h is i s d ue t o t he f ac t t ha t
t here i sn 't a g r ip o n t he wa ter f ro m a h u l l l ike t h is . Iam v ery i n terested i n t he ma ter ia l o f t he s a i l t oo a nd Ih ope t o t ry a s a i l w i th d ia mond o r l ozenge s hape p ieces , b ecause i n t he way Ic an g e t t he warp a nd t he we f t n o t p ara l le l t o t he h ead o f t he s a i l , a nd Ih ave a n i dea t ha t t here may b e s o me th ing q u i te i mpor tan t i n t h is. Baker :
D o n o t b e l ieve a l l t ha t y ou r ead a bou t t ank t es t ing o f y ach ts ;
y ou c anno t a lways b e l ieve y our r esu l ts.
Wh i le
a n u nderwa ter c u t o f f t ranso m p roved p ossib le i n t he t ank f or t he 1 2m y ach t Mar iner f or t he l ast Amer ican C up t r ia ls , i tj ust d id n o t work o u t f u l l s ca le i n wa ter . Evans :
H as t he Greenw ich f aer ing r ep l ica b een u sed b y l oca l f i sher men?
It h ink i fy ou g e t p eop le w i thou t p recon-
c ep t ions who a re a bslou te ly masters i n t he ir o wn sma l l c ra f t t o s ee h ow t he r ep l ica h and les t h is wou ld b e e xt re me ly u se fu l .
S econd ly , d id y ou s tand u p a nd r ow ,
p ush ing a s o pposed t o p u l l ing? McGra i l :
We d id t ry p ush ing , p u l l ing , a nd e ven p add l ing . y ou f or t he s uggest ion a bou t l oca l f i sher men .
2 67
T hank
McKee :
Because t he mas t was u p a nd Iwasn 't s i t t ing o n t he t hwar t t ha t i ti s c onven ien t t o r ow f ro m , Ir ecen t ly f ound myse l f p ush r owing h er f ro m t he a f ter t hwar t wh ich i s n o t n or ma l ly u sed f or r ow ing , a nd Ig ot o n s p lend id ly . n ice ly .
Yes y ou c an p ush r ow t hose b oa ts v ery
We h ave h ad wa ter men r ow ing h er , t hese a re
men who u sed t o work a n e qu iva len t t o aT ha mes wherry o n t he T a mar , a nd o ne man c an move h er , u sing h is o wn o ars m ind y ou , v ery much b e t ter t han a nybody e lse we h ave h ad r ow ing h er s o f ar , j ust o ne man r ow ing . C hr istensen :
E ar ly c urragh b u i lding i s b aske try o r d er ived f ro m b asketry , b u t S ever in b u i lt a l arge D ing le c urragh o f l ath c ons truct ion o n t he d oub le g unwa le.
S ever in :
Among t he I r ish c urraghs Id id n o t s ee t h is d istinc t ion i n t ha t t he l a th b u i l t o nes t ranspose a s y ou move a long t he c oast i n to t he b aske t b u i l t o nes .
B o th t echn iques
a re b e ing u sed a nd Ic an 't f ind t he d iv iding l i ne b e tween t he t wo . Roe l fze ma :
You wou ld h ave h ad s uch a p er fec t o ppor tun ity t o make ad oub le h u l led b oa t , Id on 't k now i ft h is was a C e l t ic c harac ter is t ic b u t ad oub le s k in l ooks much s a fer t o me .
S ever
Id on 't t hink t here i s a ny r eason t o d o s o , s he i s p erf ec t ly g ood a s s he i s .
One o f t he p rob le ms i s t ha t
t oday t he c ows a ren 't wha t t hey u sed t o b e , a nd we t r ied t o u se a l ea ther a bou t 4m m t h ick , a nd t ha t i s q u i te t h in b y modern s tandards , a nd t ha t s ee ms t o b e s u f f ic ien t . I twou ld b ev ery h ard t o d o ad oub le s k in b ecause o f t he s t i tch ing t echn iques . E d i tor ia l N o te :
Mr . W. A . B aker o f t he H ar t N au t ica l Museu m , Massachuse t ts I nst i tu te o f T echno logy , U .S .A . d esc r ibed t he b u i ld ing o f s evera l r ep l icas o r r eproduc t ions i n t he U .S .A .
These were most ly b u i l t f or Museu m
d isp lay , a l though s o me a re work ing b oa ts.
T he b oa ts
a re r ep l icas o f : I A3 0 f t . b oa t t yp ica l o f t hose c arr ied b y May f lower i n 1 620 . i
A 1 6 f t . l ogboa t , u sed a s t enders i n 1 7th c en tury U .S .A .
i i
A 3 0 f t . P o to mac R iver p lan ta t ion b oa t o f c . 1 725 .
i v
A 2 4f t . wha le b oa t u sed b y p r iva teers i n L ong I s land S ound d ur ing t he R evo lu t ion . A 2 5 f t . E ng l ish l ongboa t o f c . 1 775 .
v i
Al a te 1 9 th c en tury sma l l f i sh ing b oa t .
2 68
2 0 .
ANC IENT BOATBU ILD ING
- A PROV IS IONAL CLASS IF ICAT ION Arne Em i l C hr istensen
S u m mary A f ter d e f in ing t he l im i ts o f t he p resen t p aper a gainst t he t opic , t he a u thor d iscusses r ecen t t rends i n t he s tudy o f t he s ub jec t , w i th s pec ia l emphasis o n N or thern E urope .
T he i mpor tance o f t he c oncep ts " she l l
b u i ld ing" a nd " ske le ton b u i ld ing" a s t oo ls f or t he u nders tand ing o f b oa tb u i ld ing t echn iques i s s tressed .
Ab r ie f s urvey o f t he ma in s ource
g roups i s g iven , a nd a t en ta t ive c lassi f ica t ion o f a ncien t b oa tbu i ld ing me thods i s s ugges ted .
I ti s s tressed t ha t t he ma ter ia l i s s t i l l i nsu f-
f i c ien t f or d ef in ite r esu l ts a nd t ha t more r esearch i s n eeded o n many s ectors o f t he s ub jec t.
O f p ar t icu lar impor tance i s t he s tudy o f Ce l t ic
s h ipbu i ld ing i n Wes tern Europe , t he p oss ib le t rans it ion f ro m s he l l t o s ke leton t echn ique i nd ica ted b y l ate C lass ica l a nd e ar ly Byzan t ine wrecks , a nd t he s tudy o f l i v ing b oa tbu i ld ing t rad it ions i n Western Europe a nd t he Med iterranean . T he h uge t op ic " Anc ien t b oa tbu i ld ing methods" c an n ot b y a ny means b e t horough ly c overed b y as y mposiu m p aper , s o Ih ave s e lec ted wha t Is ee a s s o me o f t he ma in p o ints. Iw i l l d e f ine b oa ts a s c ra f t wh ich f loa t b ecause t hey d isp lace wa ter .
T h is
d e f in i t ion w i l l om i t , h owever i n teres t ing t hey a re , t he v ar ious f loa t ing d ev ices ( u sed i n mi ld c l i ma tes t o s uppor t s w i m mers ;
r a f ts a nd r eed b oa ts.
Iw i l l a lso
a rb i trar i ly , om i t t he b ark c anoes o f N or th Amer ica a nd o ther p ar ts o f t he wor ld .
Th is l eaves u s w i th t wo ma in t ypes o f v esse ls ;
b oa ts o f wood , a nd
b oa ts o f w ickerwork o r a wooden s ke le ton c overed w i th s k ins , t ex t i les o r b i tumen .
Iw i l l t ry t o g roup t he ma ter ia l a nd s ee i ft h is g roup ing c an g ive a ny
i n for ma t ion o f s ign i f icance o n t he v ar ious me thods u sed b y d i f feren t b oa tb u i ld ing " schoo ls" .
Geograph ica l ly , Iw i l l ma in ly r es tr ic t myse l f t o Europe ,
b u t Iw i l l d raw i n c o mpara t ive ma ter ia l a s If ind i tn ecessary .
F ina l ly , I
w i l l t ry t o s um u p wha t we k now , wha t we t h ink , a nd where we n eed t o p ursue f ur ther r esearch . T he ma in a im o f t he p aper i s n o t t o s o lve p rob le ms , b u t r a ther t o f or mu la te t he m , a nd p rovoke f ur ther r esearch i n to t h is , i n my o p in ion , v ery i mpor tan t b ranch o f t he h istory o f t echno logy . I n N or th- Wes tern Europe , t he t op ic h as b een r a ther i n tense ly s tud ied , e spec ia l ly w i th in t he l ast 1 5 t o 2 0 y ears. A s I s tar ted work o n my M. A . t hesis i n t he l a te 1 950s , t he f ew p ersons work ing a c t ive ly o n b oa t a rchaeo logy t ha t Ic ou ld l oca te a nd d iscuss p rob le ms w i th , c ou ld b e c oun ted o n o ne h and .
We a l l worked i n t he c l inker-bu i lding t rad i t ion ,
a nd f ew p eop le s ee md t o t ake a ny i n terest i n o ther o ld me thods o f b oa tbu i ld ing .
2 69
Luck i ly , ma t ters h ave c hanged g rea t ly ,
Many s cho lars n ow d evo te t ime t o t he
s tudy o f s h ipbu i ld ing h istory , u nderwa ter a rchaeo logy h as e xpanded g rea t ly , t o g ive much n ew ma ter ia l , a nd n ew museu ms d evoted t o s h ips h ave b een e stabl i shed .
As er ies o f f inds h as g iven
n ew i n for ma t ion , a nd t he r e-pub l ish ing
o f o ld a nd i nsu f f ic ien t ly p ub l ished s h ips h as d rawn a t ten t ion t o o ther a nd l ess s pec tacu lar t ypes t han t he N orse V ik ing S h ips , wh ich h ave h ad a t endency t o d raw mos t o f t he i n terest f ro m s cho lars a nd t he g enera l p ub l ic a l ike .
Two
j ourna ls h ave b een f ounded f or t h is a nd r e la ted t opics , C ah iers d 'Archaeo log ie S ubaqua t ique a nd T he I n terna t iona l J ourna l o f N au t ica l Archaeo logy . T hus t he f ie ld h as e xpanded i n s evera l d irec t ions.
T he ma ter ia l h as i n-
c reased , mak ing i tn ecessary t o r e for mu la te t heor ies t ha t h ave l ong b een g ene ra l ly a ccep ted , a nd t o a sk n ew q uest ions. O lof Hass löf 's p aper"Carve l c ons truc t ion T echn ique , n a ture a nd o r ig in" p ub l ished i n 1 958 h as s upp l ied t he t heore t ica l b ackground f or much o f t he r ecen t r esearch .1 H ass lo f f or mu la ted t he c oncep ts " She l l b u i lding" a nd " Ske le ton b u i ld ing" a nd d e monstra ted t ha t t hey were b e t ter t oo ls f o r esearch t han t he t er m ino logy p rev ious ly u sed ,
" Carve l" a nd " C l inker" b u i ld ing .
U sing c arve l-
c l inker t er m ino logy may l ead t o wrong c onc lus ions , a s t rue c arve l s h ips a nd smoo thsk inned s he ll -bu i l t v esse ls l ook a l ike when f in ished . i conograph ic ma ter ia l i s u sed , t h is p i t fa l l i s e v iden t .
E f . ,pe z , i ia l ly when
S he l l t echn ique a s u sed
i n c l inker b u i ld ing i s s t i l l p rac t ised , s o modern c o mpara t ive ma ter ia l c an b e much
more r ead i ly u sed i n t he " c l inker-bu i ld ing" a rea t han i n o ther p ar ts o f
t he wor ld .
I n o ther a reas , t he l i nks b e tween a nc ien t a nd modern b oa t-bu i ld ing
a re n o t s o o bv ious , a nd t hey h ave n o t b een s tud ied a nd d ocu men ted w i th t he s a me i n tensi ty a s t he c l inker-bu i ld ing t rad i t ion h as. I f we s um u p t he work o f wha t may b e c a l led t he "Hass löf s choo l" o f r es earch , ( i nc lud ing t he p resen t a u thor ) , much o f i tc en tres o n t he b asic h ypo thes is t ha t wooden s h ipbu i ld ing i n t he Med i terranean , Western a nd N or thern E urope was d one i n s he l l t echn ique u n t i l f a ir ly r ecen t ly .
I n t he N or th , b oa ts were
'
c l inker-work , i n t he Med i terranean , smoo thsk inned t enon a nd mor t ise t echn ique was u sed . was s can ty .
When H asslö f wro te h is p aper , t he Med i terranean ma ter ia l
A par tiro m t he Dashur a nd N em i s h ips , v ery l i t t le was a ccessib le
i np roper ly p ub l ished
f or m .
I n a dd i t ion t o H orne l l 's work o n t he c onnec t ion
b e tween t he modern f ra me less b oa ts o n t he N i le a nd t he Dashur b oa ts ,
2
Hasslö f ma in ly u sed i conograph ic ma ter ia l s howing s ur face d ove ta i l ing o f p lanks i n t he " dashur manner" .
H ass lö f c on trad ic ted H orne l l 's s ta te men t t ha t c arve l
b u i ld ing "must b e a n a c t o f i nven t ion" , a nd t ha t " no g radua l e vo lu t ion o f t he o ne i n to t he o ther i s c onc ievab le7 F or t he c l inker-bu i ld ing a rea , t he g radua l e vo lu t ion c an b e d e mons tra ted b y p rac t ise wh ich i s s t i l l w ith in l iv ing me mory , a nd Hass lö f s uggested t ha t s im i lar e vo lu t ion may h ave t aken p lace e lsewhere .
Hass lö f a sse mb led s o me
ma ter ia l p o in t ing t o Wes tern Europe i n t he l a te 1 5 th c en tury a s ap ossib le p lace f or t he t ransi t ion i n to c arve l work . Impor tan t i n t h is c on tex t i s t he E ng l ish p rac t ise o f g iv ing o ld c l inker h u l ls a n ew s k in i n c arve l t echn ique . T he s tudy o r r ecen t b oa tbu i ld ing w i th in t he c l inker-bu i lding a rea h as p layed a n i mpor tan t r o le i n much o f t he work p ub l ished b y t he " Hasslö f s choo l" , a nd i th as b een p roved t ha t t h is i s as ource o f p r i me i mpor tance f or t he p roper u nders tand ing o f a rchaeo log ica l b oa t f inds . 2 70
One e xa mp le i s O le C rum l in-
P edersen 's p aper o n t he h u l l s hape a nd c ons truct ion o f t he " Kog" t ype .
3
C oncern ing t he o ther me thod o f s he l l b u i lding , s h ips e xcava ted u nder wa ter i n t he Med i terranean i n r ecen t y ears h ave g iven n u merous e xa mp les o f t enona nd mor t ise work t ha t mus t h ave b een b u i l t s he l l f irs t . I ti s n ow g enera l ly a ccep ted t ha t t h is me thod was u sed b y Egyp t ian , Greek Pun ic , R o man , a nd B yzan t ine s h ipwr igh ts , b u t i ti s s t i l l n o t k nown whe ther t h is was t he o n ly me thod i n u se i n t he Med i terranean .4
O ther f inds , h owever ,
h ave g iven i nd ica t ions o f a much g rea ter a ge f or t he t ransi t ion f ro m ,s he l l t o s ke le ton work t han H asslö f s uggested .
F inds l ike t he 4 th a nd 7 th c en tury Yassi
Ada s h ips a nd t he P an tano L ongar ino s h ip i nd ica te a mixed s he l l-ske le ton t echn ique s trange ly s im i lar t o t he 1 9 th c en tury S cand inav ian me thod o f bu i lding sma l l f re igh ters w i th a c l inker b o t to m a nd c arve l t opsides.
i n t hese c ases ,
5
i n S candinav ia , t he s h ipbu i lder wou ld s hape t he b o t to m o f h is h u l l i n s he l l t echn ique , t o e nsure t ha t t he s hape d eve loped p roper ly t o g ive g ood u nderwa ter l ines.
F loors , f u t tocks a nd t op t i mbers a re t hen f i t ted , a nd t he r e ma inder
o f t he h u l l i s c arve l p lanked f or s treng th a nd s turd iness. I n N or thern E urope t he work d one b y Marsden a nd E l l mers o n e ar ly C e lt ic s h ips h as w idened o ur k now ledge c onsiderab ly a nd s hown t ha t t he p ic ture i s more c o mp l ica ted t han p rev iously a ssu med .
u
C e l t ic s h ipwr igh ty h ad i t s own
me thods , s ee m ing ly n o t r e la ted t o e i ther t enon a nd mor t ise o r c l inker work . I n ar ecen t p aper Marsden h as a rranged t he N or th E uropean ma ter ia l f ro m t he R o man p er iod i n s ix g roups .
One o f t hese i s Med i terranean ( mor t ise a nd
t enon work ) , o ne i s N ord ic ( c l inker ) . C e l t ic s h ipbu i ld ing t rad i t ions.
T he r e ma in ing f our a re s een a s d i f feren t
F ro m i mpor tan t f inds , Marsden l abe ls t he m
t he B lack fr iars , Zwa m merda m , N ew Guy 's H ouse a nd U trech t t ypes.
7
N ew ma ter ia l i s c ons tan t ly b e ing r epor ted , a nd t he t ime may n o t y e t b e r eady f or g enera l c onc lusions , b u t i tw i l l b e wor thwh i le t o s u m mar ize t he s ources a va i lab le a nd s ee h ow t hey c an b est b e u t i lised .
Our most impor tan t
s ources n a tura l ly , a re t he a c tua l r e ma ins o f a nc ien t v esse ls.
T he c a ta logues
r ecen t ly c o mp l ied b y E l l mers a nd Mu l ler -W i l le s hows h ow e x tensive t h is ma ter ia l i s i n t he N or th a nd N or thwest o f E urope ,
8
a nd t he n u mber o f f inds
w i l l s ure ly mu l t ip ly i n t he f u ture , d ue t o u nderwa ter work .
F or t he Med i ter-
r anean n o c o mp le te c a ta logue e x ists , t he mos t e x tensive i s t he o ne d rawn u p b y B asch ,
9
b u t n ear ly e very s eason n ew f inds a ppear w i th a r e markab le amoun t
o f t he wood i n tac t . Many o f t he Med i terranean v esse ls , among t he m h igh l igh ts l i ke t he Kyren ia s h ip , t he Pun ic wrecks f ro m S ic i ly a nd t he C heops s h ip , a re s t i l l awa i ting f ina l p ub l ica t ion , s o t he ir f u l l s ign i f icance c an o n ly b e g uessed .
T he s er ies
o f p apers s tar ted b y t he I JNA o n "Med i terranean h u l l t ypes c o mpared" w i l l s ure ly h e lp t o c lar i fy ma t ters.
1 °
Anc ien t v erba l a nd i conograph ica l s ources h ave b een f requen t ly a nd o f ten b r i l l ian t ly u sed i n t he s tudy o f wha t a nc ien t s h ips l ooked l ike , a nd t o s o me e xt en t a lso , h ow t hey were made . c r i t ic is m .
H owever , t hey p ose g rea t p rob le ms o f s ource
A s t he f inds a re s t i l l l ack ing , t he i conograph ic s ources a re s t i l l
o ur p r i me s ource f or u nderstand ing r igg ing , b u t a s as ource f or h u l l s hape a nd me thods o f b u i ld ing , t hey w i l l o f ten n o t b e f u l ly u nderstood u n t i l a c tua l r e ma ins o f t he s h ips a re f ound .
2 71
F ig . 2 0,1
With 100 y ears b etween t he m , r ough ly 4 5 g enerat ions o f b oa tb u i lders , t he t wo b oa ts c lear ly d e monstra te l ong , c on t inuous l ines o f t rad it ion .
Above , t he sma l lest b oa t f ound i n t he G oks tad b ur ia l
o f C . 8 50 A .D .
Be low , t rad it iona l b oat b u i lt n ear B ergen , Wes tern
Norway a round 1 967 A .D .
P ho to T er je O lsen.
Ancien t woodwork ing t oo ls a re a s ource o f impor tance , when i tc an b e d e mons tra ted t ha t t hey h ave b een u sed i n s h ipbu i ld ing .
A na lys is o f t oo l marks
o n t he s h ips w i l l s upp le men t t he t ools t he mse lves a s as ource . T he r esu l ts o f modern e xper i men ts c annot b e c a l led a s ource i n t he u sua l d e f in i t ion o f t ha t w ord , b u t t hey a re v ery h e lp fu l i n t he r esearch p rocess , f or i ns tance i np rov ing t ha t at heory i s i mposs ib le o r i mprobab le i n p rac t ise .
1 1
F ina l ly , Iw i l l i nc lude modern c o mpara t ive ma ter ia l among t he s ources . F or t he c l inker-bu i ld ing a rea , i t s v a lue h as b een p roved i n f u l l ( F ig . 2 0.1 ). A s trik ing e xa mp le o f h ow s uch ma ter ia l c an b e u sed a cross c u l tura l b orders i s t he p aper b y L . C asson o n t he R o man t o mbs tone o f t he s h ipwr igh t P . L ong id ienus . 1 2 U sing c o mpara t ive ma ter ia l f ro m t he c l inker-bu i ld ing a rea a nd t he r esu l ts o f u nderwa ter a rchaeo logy , C asson g ives t he p roper e xp lana t ion o f t he s cene : t he s h ipwr igh t i s f i t t ing a r ib t o t he f in ished s he l l o f t he b oa t h e i s b u i lding . T he v ar ia t ion i n t he s ources a s l i s ted a bove , g ives r ich p ossib i l i t ies o f a ttack ing p rob le ms f ro m many a ng les , b u t a t t he s a me t ime t here a re g rea t p rob le ms i nvo lved i n t he many d i f feren t a spec ts o f a na lysis a nd s ource c r i t ic is m n ecessary . D ocumen t ing a n e xcava t ion , o r j udg ing t he q ua l i ty o f s im i lar work d one 5 0 y ears a go makes i tn eccessary t o u se me thods o f s ource c r i t ic is m f ar d i f feren t f ro m t hose n eeded t o i n terpre te a n a ncien t t ex t o r s ke tchy s h ip p ic tures . I ti s h ard ly t o b e e xpec ted t ha t t he s ame s cholar s hou ld p osess t he t ra ini ng a nd e xper ience n ecessary t o a na lyse t oo l marks o n a nc ien t wood , s tudy t ex ts i n G reek , O ld N orse a nd C e l t ic , w ie ld t he a xe o r o ar i n ac o mpara t ive e xper i men t , a nd i n terv iew a r e t ired a nd p robab ly d ea f b oa tbu i lder , e qua l ly we l l .
T ea mwork i s t he o bv ious s o lu t ion t o t he p rob le m , o f c ourse .
Dur ing
t he f ie ldwork d one b y t he S cand inav ian Mar i tiMe H is tory Work ing Group i n t he y ears 1 965-67 , we a l l f e l t t ha t o ur d i fferen t b ackground t ra in ing , i n e thnology , h istory , n ava l a rch i tec ture a nd a rchaeology , g ave g rea t a dvan ta ps o ver work ing i n ag roup where a l l h ad t he s a me t ra in ing , o r work ing a lone .1 3 H owever , t hose o f u s who a re a rchaeo log ists , s hou ld s tr ive f or a s b road a k nowledge a s p oss ible o f a l l t ypes o f s ources . I ti s o ur j ob t o i n terpre te mu te a r t i fac ts , t o a na lyse f ragmen ts o f al ost t ota l i ty . The "mode l" we e stabl ish t o e xp la in o ur f inds , h ow t he a r t i fac ts were made a nd u sed b y e ar ly man , i s o f c ourse l im i ted b y o ur own k now ledge , e xper ience a nd imag ina t ion . The w ider t he k now ledge a nd e xper ience i s , t he r icher t he mode l g e ts , i n d e ta i ls o r a l terna t ives.
On t he o ther h and t he s earch f or " para l le ls" must
b e k ep t w i th in t he l im i ts o f c o m mon s ense . T here h ave b een many s ins c om i t ted , where t he " para l le l" i s v isua l ly s tr ik ing , b u t h as n o p ossib le c u l tu ra l c onnec t ion w i th t he a nc ien t ma ter ia l . t e mper ing a t oo r ich i mag ina t ion .
H ere e xper ience w i l l h e lp i n
F or t h is o ccasion , Iw i l l l eave mos t o f t he s ources men t ioned a bove a nd c oncen tra te o n t he s h ips t hemse lves . On t he b asis o f t he a va i lable s ources , Ih ave t r ied a c lass if ica t ion o f t he " anc ien t b oa tbu i ld ing me thods" k nown t o u s , w i th in t he l im i ts s ta ted i n t he i n troduc t ion . 1 .
Wooden b oa tbu i ld ing
2 .
S k in b oa tbu i ld ing 2 73
We c an d iv ide f ur ther a ccord ing t o b u i ld ing t echn ique . 1 .1 .1 . L og b oa ts , made b y h ol lowing a l og w i th t oo ls , f ire o r b oth . S hape may r e ta in t he r ound c ross s ec t ion o f t he l og , o r t he b oa t may h ave h ard c h ines b o th i nside a nd o u ts ides , g iv ing a more o r l ess b ox l ike s truc ture . Boa ts o f t h is c a tegory h ave b een i n u se f ro m a t l east Meso l i th ic t imes t o w i th in l i v ing me mory i n Europe , a nd t hey c an s t i l l b e s een i n u se i n many p ar ts o f t he wor ld . 1 .1 .2 .
L og b oa ts w idened a f ter h o l low ing w i th t he h e lp o f f ire a nd wa ter .
Archaeo log ica l f inds d a te b ack t o t he R o man p er iod , a t l eas t ; t he me thod i s s t i l l u sed i n p ar ts o f E as tern E urope .
The me thod i s a lso r epor ted f ro m t he
Far E ast a nd t he n or thwes t c oas t o f C anada . 1 .2 .
C l inker b u i ld ing .
o r wooden n a i ls .
P lanks o ver lap , a re j oined b y s ewing , i ron n a i ls
F inds p ush t he d a te o f t he me thod b ack t o c . 3 50 B .C .
b u t i t may b e o lder .
E vo lu t ion o f t his me thod f ro m e i ther l og b oa t o r s k in
b oa t h as b een much d iscussed .
T he me thod c an b e s tud ied t oday i n t he
b oa tshops o f S cand inav ia , Br i ta in a nd t he B a l t ic . 1 .3 .
Smoo th s k inned p lank b oa ts , t he s trake e dges j o ined b y mor t ise a nd
t enon , l ash ings , i ron s tap les o r i ron n a i ls d r ived o b l ique ly .
I n E gyp t , f inds
g o b ack t o t he O ld K ingdo m ; t he i ron n a i led v ar ia t ion h as b een i n u se we l l i n to t h is c en tury .
S im i lar e dge j oin ing me thods h ave a lso b een u sed a nd a re
s t i l l u sed i n t he F ar E ast a nd t he P aci f ic . Ih ave c hoosen t o i nc lude i n t h is g roup t he N or th F err iby a nd B r igg v esse ls , s ee ing t he m a s an or thern v ar ia t ion o f Med i terranean B ronze Age b oa tbu i ld in .g .
I ti sp robab le t ha t t he g roup a s a who le i s d er ived f ro m l og
b oa ts . I n Egyp t , r eed b oa ts d e f in i te ly i n f luenced t he s hape o f wooden v esse ls , a nd t o s o me e x ten t p robab ly a lso t he ir c ons truc t ion . 1 .4
" Ce l t ic"
1 4
p lank-bu i l t b oa ts w i th h ard c h ines .
F inds a nd l i terary
s ources g ive a t erm inus a n te q ue m o f t he 1 s t . c en tury B .C. Modern d er iv a t ives may e x ist , i n t he " Nachen" t ype o f r ivercra f t u sed o n t he Ma in a nd Rh ine . The a ncestry o f t he t ype , o r r a ther g roup o f f inds , s ee m t o b e l og b oa ts o f t he h ard c h ine v ar ie ty . 1 .5 " Ce l t ic" p lank b oa ts o f t he " Ho lck" t ype . S o f ar , f inds a nd l ingu ist ic e v idence g ives a t er m inus a n te q ue m i n t he 2 nd c en tury A .D . Modern c l inckerbu i l t v esse ls o f t he " pra m" t ype , may b e d er ived f ro m t he H o ick . 1 .6 .
Ances try s ee ms t o b e l og b oa ts o f t he 1 .1.2 . t ype . T rue c arve l w ork , d e f ined a s s h ips where p lanks a re n a i led t o
p re-erec ted f ra mes , t he p lanks n o t b e ing f astened t o o ne a no ther . k nown , p robab ly l a te C lassica l p er iod i n e ar ly f orm . d eve loped f ro m g roup 1 .3 .
Age u n-
T he me thod may h ave
S t i l l i n c urren t u se .
I tw i l l b e s een t ha t my g rouping o f t he C e l t ic b oa ts d i f fer f ro m t ha t s uggested b y Marsden .
Ih ave c hoosen t o g roup t he B lack fr iars a nd Zwa m merda m t ypes
t oge ther , a nd my g roup 1 .5 . c overs Mardens U trech t a nd N ew Guy 's H ouse g roups .
T h is g roup ing p laces more we igh t o n h u l l s hape t han o n t echn ica l
d e ta i ls , a nd may b e a n o ver-s i mp l if ica t ion . The s k in b oa ts s hou ld b e s ubd iv ided i n 2g roups . 2 74
2 .1 B oa ts where t he s ke le ton c onsists ma in ly o f l ong i tud ina l s tr ingers , c onnec ted b y r ibs o rb o t to m a nd s ide s tru ts . A l l a rc t ic s k in b oa ts f a l l i n to t h is g roup , whe ther t hey a re o f t he " Um iak" o r " Kayak" t ype . Kayaks g ene ra l ly h ave r ibs o f t h in b en t l a ths i nsi ch t he s tr ingers , r esu l t ing i n mu l t ic h ine h u l l s hape , wh i le t he um iaks g enera l ly h ave s tra igh t b o t to m a nd s ide b a t tens s epara t ing t he s tr ingers , a nd t he n umber o f s tr ingers i s sma l ler t han i n ak ayak . 2 .2 work .
B oa ts where t he s ke le ton i s i nb aske twork , o r d er ived f ro m b aske tT h is g roup h as a w ide g eograph ica l d is tr ibu t ion a nd i ti s u ncer ta in
whe ther t here h as b een c u l tura l c on tac t b e tween t he v ar ious a reas , I nd ia , t he Midd le E ast a nd C e l t ic Wa les a nd I re land . Many o f t he c urraghs a s b u i l t t oday h ave a l a th s ke le ton , b u t e ven h ere t he b aske t work a ncestry s eems c ert a in when t he c urragh - c orac le g roup i s s een t oge ther . I ti s w i th s o me h esi ta t ion t ha t Io f fe rt h is c lassi f ica t ion , a nd Iam f u l ly aware t ha t a ny g roup ing o f t he ma ter ia l w i l l f orce s o me o f i ti n to t oo r ig id " boxes" . A f ter a l l , o n ly a g enera t ion a go , wooden s h ipbu i ld ing was e i ther " carve l" o r " c l inker" . We s t i l l n eed t o k now much more a bou t t he v ar ia t ions i n t he " reper toire" o f t he o ld s h ipbu i lders , b e fore o ur g roups c an h ave a ny h ope o f g e t ting c lose t o r ea l i t iy . H owever , c lassi f ica t ion a nd r ec lassi f ica t ion i s an ecessary t oo l i n s tudying a n a rchaeo log ica l ma ter ia l , a nd Ih ope my c lassi f ica t ion w i l l make s o me t echn ica l d i f ferences a nd s im i lar i t ies more v is ible . T he s epara t ion o f t he s k in b oa ts i n t o t wo c a tegor ies i s n ecessary , a s b oth h ave b een u sed t oge ther i n t he d iscussion o n whe ther t he s k in b oa t o r t he l og b oa t i s t he a ncestor o f c l inker-bu i l t c ra f t .
Wi th t he d anger o f s tar t ing t ha t
d iscussion a ga in , i ts hou ld b e p oin ted o u t t ha t a l l o ther g roups o f p lank-bu i l t b oa ts h ave a wooden a nces try . T h is i s s t i l l v a l id i f we i nc lude P o lynesia a nd t he j unks o f C h ina a nd J apan . A s Is ee i t , t he s k in ( and r eed ) b oa ts a re b lind a l leys . T hey d eve lop w i th in t he ir own l im i ts , s o me t i mes t o g rea t p erf ect ion . T hey may i n f luence t he s hape o f wooden b oa ts , b u t v ery s e ldo m d o t hey i n f luence t he ir c onstruc t ion . Egyp t i s t he e xcep t ion t o t he r u le , t he s yste m o f l ong i tud ina l b eams a t d eck l eve l s een i n t he C heops b oa t a nd i nd ica ted o n many mode ls may h ave b een t aken o ver f ro m p apyrus r af ts w i th wooden r ein force men ts . G enera l ly we c an s ay t ha t where wood was a va i lab le , p r im it ive man make h is b oa ts o f w ood , a nd wooden t echno logy h as d o mina ted b oa tb u i lding e ver s ince , u n t i l s teel a nd f i breg lass was i n troduced . ( Excep t ions d o e x is t , n o tab ly among mob i le g roups o f h un ters where p ortage i s o f ten n ece ssary , a s among t he I nd ians o f N or th Amer ica .) I n t he Med i terranean t rad i t ion o f s h ipbu i ld ing , a n e ar ly f ind l i ke t he C heops s h ip s hows u s t ha t Egyp t ian s h ipwr igh ts mastered t he b u i ld ing o f v ery l arge wooden v esse ls e ar ly i n t he O ld K ingdo m , w i th t he wonder fu l r e l ie fs f ro m t he g raves o f T i a nd o thers a s s upp le men tary e v idence t o s how u s h ow t he s h ipwr igh ts w orked .1 5 T here a re h uge t imbers i nvo lved , t he l arges t p lank i n t he C heops s h ip i s 2 3m l ong . T h is , t oge ther w i th t he F err iby b oa ts a nd t he l arge war c anoes o f O cean ia , s hows u s t ha t i ron t ools a re n o t n ecessary f or t he b u i ld ing o f g rea t v esse ls , t hey a re w i th in t he p ossib i l i t ies o f s tone a nd b ronze a ge t echnology .
2 75
E ven w i th t hese h uge t imbers , a l l f asten ings a re wood a nd r ope . I n f ac t t he u se o f me ta l n a i ls a nd b o l ts b e long t o aw e l l d eve loped i ron a ge t echno logy . T he b ronze a ge n ever g o t a round t o t he g enera l u se o f n a i ls , t he ma ter ia l w as t oo e xpens ive , o r t he i dea h ad n ot y e t o ccurred . When t h ick wood i s u sed , f or s h ips ' t imbers o r o ther s truc tures , d owe ls a nd t reena i ls a re n a tura l s o lu t ions t o t he p rob le m o f f as ten ings . When t h in wood i s u sed , t here w i l l b e ad anger o f t he n a i ls p u l l ing t hrough , a nd n o t e nough wood t h ickness t o c u t mor t ises. T he o n ly p ossib le p re-iron f as ten ing me thod w i l l b e s ew ing o r l ash ing w i th t he a va i lab le f i bres . H owever , t h ick wood may b e l ashed a s we l l a s t reena i led o r t enonfas tened , o bv ious e xa mp les a re t he C heops b oa t . , a nd a n umber o f t he c anoe c ons truc t ions o f P o lynesia . We d o n o t k now when t enons t ook o ver c o mple te ly i n t he Med i terranean s h ipbu i ld ing t rad i t ion , a nd s ew ing was d iscon t inued , b u t t enons a re u sed i n t he C heops b oa t , a nd t hey c an b e s een i n s o me o f t he O ld K ingdom r e l ie fs . Un t i l l a te C lass ica l t imes , s he l l b u i ld ing s ee ms t o h ave r e igned s upre me i n t he Med i terranean , a s i td id i n t he N or th , w i th in t he c l inker-bu i lding t err i tory .
T he a ids a nd
me thods u sed b y t he Med i terranean s h ipwr igh ts t o o b ta in t he r igh t h u ll s hape a re n o t k nown , b u t Van D oorn inck h as f ound e v idence o f t he midsh ip r ib b e ing e rec ted e ar ly d ur ing t he b u i ld ing o f t he 4 th c en tury Y assi Ada s h ip , c lear ly t o a c t a s a midsh ip mou ld t o g u ide s hape .1 6 T he C e l t ic b u i lding me thods s how g rea t v ar ia t ions , e ven w i th in r e la t ive ly sma l l n u mbers o f f inds k nown . C harac ter is t ic a re t he massive t imbers u sed , t he e ar ly u se o f h eavy i ron f as tenings , a nd t he h igh f requency o f h ard-ch ine v esse ls . S o me o f t he C e l t ic v esse ls a re c lear ly s he l l-bu i l t . T he U trech t s h ip , a nd p robab ly t he Zwa m merda m b oa t 3 may b e e xpanded d ugou ts w i th a dded washstrakes , wh i le t he B lack fr iars t ype may b e e xa mp les o f e ar ly c arve l w ork , Iam s t i l l n o t q u i te s ure . S um m ing u p , i t must b e s tressed t ha t t h is p ar t icu lar f i e ld o f r esearch i s s t i l l n ew a nd t here a re p len ty o f o ppor tun i t ies f or p ioneer work .
Much s t i l l
r e ma ins t o b e d one i n t he s tudy o f c l inker b u i l t v esse ls , b u t f or t he t ime b e ing , t h is i s t he b est-s tud ied b ranch o f t he t op ic . I n t he Med i terranean a p a t tern c an b e s een , b u t much o f t he b est ma ter ia l i s s t i l l o n ly t e mporar i ly p ub l ished a nd t he p a t tern may h ave t o b e mod i f ied . We n eed t o k now much more a bou t t he C e l t ic t rad i t ion i n wooden s h ipbu i lding , i n i t s v ar ious f orms . T he a rcha eo log ica l ma ter ia l w i l l s ure ly c o me , i nt he mean t i me , much r e mains t o b e d one o n r ecen t b oa tbu i ld ing w i thin t he a rea , a nd h ere f ie ldwork i s u rgen t ly n eeded .
T rad i t iona l c ra f ts a re o n t he way o u t a l l o ver E urope , a nd w i th t he
l as t o f t he c ra f ts men , al i ne o f t rad i t ion d isappears t ha t c ou ld g ive b o th e thn o log is t a nd a rchaeo log is t i n for ma t ion t ha t c anno t b e o b ta ined e i ther f ro m t he s o i l o r a rch iva l ma ter ia l . T he r ecen t b ook b y F rancois B eaudou in 1 7 o n F rench v esse ls s hows u s t he g rea t v ar ia t ion i n h u l l a nd r igg ing t ha t c an b e f ound w i th in o ne c oun try . A s f or S pa in a nd P or tuga l , we k now wha t v esse ls l ooked l i ke , t he i n forma t ion s t i l l e x ist ing i nt he y ards a nd among r e t ired b oa tbu i lders h as n o t y e t b een f u l ly e xp lored .1 8 T h is i s a lso t he c ase i n t he Med i terranean . Mor t ise a nd t enon work i s n o l onger i s u se , a s f ar a s we k now , b u t t he d ove ta i led s ur face t enons u sed i n t he Dashur b oa ts were r ecorded b y Adm ira l P ar is o n F rench r iver c raf t i n t he l ast c en tury .1 9 Who k nows wha t o ne may f ind? Ano ther l i ne o f
2 76
r esearch wh ich s hou ld p rov ide f ru i t fu l i s t he s tudy o f c arve l p ract ice i n sma l l y ards .
T he u se o f d raw ings a nd mou ld l o f t h as n o t y e t p ene tra ted t o a l l d is-
t r ic ts , a nd t he " predrawing" me thods o f c arve l b u i ld ing s hou ld b e r ecorded i n a s many p laces a s p ossible .
T he d i f ferences i n a pproach b e tween s he l l
b u i lders a nd s ke le ton b u i lders , t he v ar ious a ids u sed i n s hap ing h u l ls , i s i nf or ma t ion t ha t c an s t i l l b e a ssemb led i n f i e ldwork where t he s pade i s l e f t a t h o me . A s h as b een t he c ase i n t he N or th , l i v ing t rad i t ion may e xp la in o bscure p oin ts i n v erba l a nd i conograph ic s ources. I tw i l l e nr ich o ur "mode l" f or u se o n a rchaeo log ica l ma ter ia l . T he s ys te ma t ic s tudy o f t he Med i terranean wreck ma ter ia l w i l l s ure ly l ead t o ag rea ter u nderstand ing o f h ow h u l l s hapes a nd b u i ld ing me thods d eve loped f ro m t he C heops s h ip t o l a te C lassica l a nd B yzan t ine s h ipbu i ld ing , a nd o n t o t he t rue c arve l h u l ls o f Vene t ian r ena issance s h ipbu i lders . Bu t It h ink t ha t t he k ey
t o ad eeper u nderstand ing o f s h ipbu i lding h is tory i n
Western a nd S ou thern E urope l i es n o t i n t he p ast , b u t i n t he p resen t , i n r ec ord ing l i v ing b oa tbu i ld ing t rad i t ions .
2 77
F ig . 2 0.2
S he l l b u ild ing f or d if feren t w a ters. Wide ly s epara ted i n t ime a nd s pace b oth p ictures s how s h ips b u i lt i n s hel l t echn ique. T he Egyp t ian s h ipwr igh ts f asten t he ir s h ip w ith t enons : W il l ia m t he Conqueror h ad h is v esse ls b u i l t b y t he c l inker method o f h is S cand inav ian a ncestors - G . S te indor f f , F . S ten ton .
NOTES 1
0 . H asslöf .
' Carve ' c onstruc tion t echn ique , n a ture a nd o r ig in .'
F o lk-L iv XX I-XX I I .
S tockho lm 1 958 .
An e xpanded a nd u nda ted v er-
s ion o f t h is p aper i s p ubl ished i n S h ips a nd S h ipyards , S a i lors a nd
2 3
F isher men .
E d . H asslö f , H ennings e n , C hr istensen .
J . H ornel l .
Wa ter Transpor t .
0 .. C rum l in-Pedersen . t ypes h istor ie .
C a mbr idge 1 946
P .
Copenhagen ,
2 13 f .
' Cog-Kogge-Kaag , t raek a f e n f r isisk s k ibs-
Hande ls o g S O far ts museet p a Kronborg , Arbog 1 965.
H e lsingSr . 4
The mos t r ecen t g enera l s urvey o f t he ma ter ia l i s L . C asson . a nd S ea mansh ip i n t he Ancien t Wor ld .
5
Hasslö f 1 958 p . 5 6.
6
D . E l l mers .
' Ke l t ischer S ch i ffbau .'
J ahrbuch d es Ro m isch-
Ger man ischen Z en tra l museu ms Ma inz.
1 969 .
D . E l l mers.
Fruh-
mi t te la l ter l iche Hande lssch i f fahr t i n Mi t te l- u nd N ordeuropa . Marsden .
A Ro man S h ip f ro m B lack fr iars , L ondon.
P . Marsden .
S h ips
New Y ork 1 971.
P .
London 1 966.
' A B oa t o f t he Ro man p er iod f ound a t Bruges , Belg iu m
i n 1 899 , a nd r e la ted t ypes.
I JNA v ol . 5 -1 L ondon . 1 976.
7
Marsden 1 976 p . 4 1 f .
8
D . E l l mers .
Fruh m i t te la l ter liche H ande lsch i ffahr t i n Mit te l- u nd
N ordeuropa .
Neu munster 1 972 M. Mu l ler -W i l le :
B oot . 2 5/26. 9
' Besta t tung im
S tud ien z u E iner N ordeuropa ischen Grabsi t te .'
O f fa v o l.
Neu munster 1 970 .
L . Basch .
' Anc ien t wrecks a nd t he a rchaeology o f s h ips .
I JNA
v ol . 1 , p . 1 2 f . 1 0
"Med i terranean h u l l t ypes c o mpared ."
A s er ies o f p apers c o m mencing
i n I JNA v o l . 5n r . 2 . 1 1
S . McGra i l .
Mode ls , r ep l icas a nd e xper i men ts i n n au tica l a rchaeology .
The Mar iner 's Mirror 6 1. 1 2
L . C asson .
L ondon 1 975 .
' Ancien t S h ipbu i lders , n ew l igh t o n a n o ld s ource .
Transac tions a nd P roceed ings o f t he Amer ican P h i lo log ica l Associa t ion . XC IV . 1 3
N ew Y ork 1 963 .
S o me o f t he t heorec t ica l v iews r eached i n o ur d iscussions , a s we l l a s s o me p rac t ica l r esu l ts o f r esearch , w i l l b e f ound i n t he b ook S hips a nd S h ipyards , S a i lors a nd F isher men , e d . Hasslöf , H enn ingsen , C hr istensen , C openhagen 1 972 .
1 4
Dur ing t he Greenwich c on ference , t he p hrase " Ce l t ic s h ipbu i lding" me t s o me o pposi t ion .
As n one o f t he o ther n a mes s uggested f or t h is g roup
o f s h ip f inds was e n t irely c onv incing , Ip re fer t o f o l low t he t er m u sed b y Marsden a nd E l l mers. 2 79
1 5.
Abde l Mone i m Abubakr a nd Ahmed Y ousse f Mus ta fa . b oa t o f Khu fu .' s kunde .
1 6 .
1 7 . 1 8.
Bei trage z ur Agypt ischen b au forschung u nd A l ter tu m-
He f t 1 2 .
Wiesbaden 1 971.
F .H . v an Doorn inck .
' The 4 th c en tury wreck a t Yassi Ada .'
v ol . 5n r . 2 .
L ondon 1 976.
F . B eaudoin .
Ba teaux d es C o tes d e F rance .
I JNA
Grenob le 1 975 .
The work o f 0 .L . F i lgue iras s hows h ow much i nfor ma t ion o ne c an g e t f ro m l iv ing t rad i t ion .
1 9 .
' The f unerary
Ad m ira l Par is .
e .g . Raboes d a E squadra Negra .
S ouven irs d e Mar ine p ar t 2p la te 6 4.
d e l 'Adour ) .
2 80
P or to 1 956. ( Ba teau d ragueur
2 1.
CELT IC SH IPS OF EUROPE P e ter Marsden
S u m mary T he r ecen t i den t i f ica t ion o f af am i ly o f s h ipbu i ld ing t rad i t ions i n c ent ra l a nd n or th-western Europe d uring t he Ro man p er iod a nd l a ter h as
o pened u p new areas o f s tudy i n t he h is tory o f s h ip t echno logy , p art icu lar ly i n mak ing more p recise i n terpre ta t ions p ossib le . T he v esse ls d iscussed i n t h is p aper a re
c lass if ied
B lack fr iars , as eago ing s a i l ing s h ip ; T ha mes r iver b arge ;
i n to f our b asic t ypes - f irst ly s econd ly , N ew Guy 's H ouse a
t h ird ly , Zwa m merda m a l arge r iver b arge c o m-
mon o n t he Rh ine a nd i n S w i tzer land ;
a nd f our th ly , U trech t a no ther
t ype o f r iver b arge f ound o n t he Rh ine . Me thods o f c u t t ing t he t imber t o b u i ld t he s h ips a re c onsidered , a nd t he l arge s ize o f t he v esse ls , wh ich i s i ncons istan t w i th t he ir p r im it ive c onstruc t ion d oes s uggest t ha t p r ior t o t he R o man i nvas ion t he v esse ls were most ly o f much sma l ler s ize , a nd t ha t t he ir l arge s ize d ur ing t he R o man p er iod was d ue t o t he s udden d e mands o f av ast ly i ncreased v olume o f t rade . B e tween S cand inav ia ,a nd t he Med i terranean b asin t here l i es a n a rea wh ich i nc ludes t he Br i t ish I s les , n or thern F rance , B e lg iu m , t he N e ther lands , Wes t Ger many a nd S w i tzer land i n wh ich v ery l i t t le was u n ti l r ecen t ly k nown a bou t e ar ly n a t ive s h ipbu i ld ing t rad i t ions.
The c l inker t rad i t ion o f S cand inav ia,
a s i l lustra ted b y t he N yda m b oa t o f t he 4 th c en tury A .D ., a nd l a ter b y t he V ik ing s h ips s uch a s Oseberg , Goks tad , T une a nd R osk i lde , i s f a mous , wh i le f ar t o t he s ou th t he c lassica l s h ipbu i ld ing t rad i t ion o f t he Med i terranean a s s hown b y t he G reek s h ip o f t he 4 th c en tury B .C . f ro m Kyren ia , a nd b y t he l a ter R o man s h ips f ro m Lake N em i a nd F ium ic ino i n I ta ly , Yass i Ada o f f T urkey , a nd Grand Cong loue o f f France a re n ow e qua lly we l l k nown . Bu t o f t he r eg ion b e tween t he t wo l i t t le was k nown u n t i l 1 962 when p ar t o f al arge s eago ing s h ip o f t he s econd c en tury A .D . was e xcava ted i n t he b ed o f t he Tha mes , a t B lack fr iars , i n t he C i ty o f L ondon . d i f feren t f ro m t he o ther d iscoveries
Th is s h ip was c o mp le te ly
a nd was t he f irst r ecogn ised e xa mple
o f wha t h as s ince b een r a ther l oose ly t ermed t he ' ce l t ic ' t rad i t ion o f s h ipb u i ld ing .
S ince t hen o ther d iscover ies h ave b een made , o r t he s ign if icance
o f e ar l ier f inds r ecogn ised , a nd i ts ee ms t ha t t here was d ur ing t he R o man p er iod a f am i ly o f ' ce l t ic ' s h ipbu i ld ing t rad i t ions e ach h av ing much i n c o m mon w i th t he o thers .
Ih ave s u m mar ised mos t o f t hese d iscover ies i n ar ecen t
pub l ica t ion ( Marsden , 1 976 ) , b u t i n a dd i t ion t o my r esearch much v a luab le work i n t h is f ie ld h as b een u nder taken b y o thers , p ar t icu lar ly b y Dr . De t lev E l l mers , D irec tor o f t he G er man Mar i t i me Museu m a t Bre merhaven ( Ea r ners ,
2 81
1 969 ) , b y Maar ten d e Weerd o f Amsterda m Un iversi ty ( de Weerd a nd H aa lebos , 1 973 ) , a nd b y B ea t Arno ld a nd Miche l Eg lo f f o f N eucha te l Museum i n S w i tzer land ( Arno ld , 1 974 ; Eg lo f f , 1 974 ) . A t l east e igh teen ' ce l t ic ' s h ips a nd b oa ts ( exc lud ing d ugou ts ) , t h ir teen o f R o man d a te , h ave n ow b een i den t i f ied i n c en tra l a nd n or th-wes tern E urope . a nd Iu nders tand t ha t s evera l o ther u npub l ished d iscover ies h ave o ccurred . Very l i t t le d e ta i l o f mos t o f t hese f inds h as b een p ub l ished , s o a t t h is s tage i ti s n o t p oss ib le t o make a d e ta i led a na lys is o f t he ir s ign if icance .
N o t o n ly
d o t hese v esse ls t e l l u s much t ha t i s n ew a bou t a nc ien t s h ipbu i ld ing t echno logy a nd t he u se o f s h ips , b u t a lso t hey must a l ter many l ong h e ld t heor ies a bou t t he o r ig in a nd d eve lop men t o f e ar ly s h ips i n n or th-west E urope . F or e xa mp le t he o ver lapp ing o f p lanks was s o me t imes u sed ( Marsden , 1 976 , 4 7) , s o i ti s u n l ike ly t ha t t he c l inker me thod o f s h ipbu i ld ing t ha t was i n troduced i n to t he c e lt ic a rea d ur ing t he Migra t ion P er iod was s uch a s tranger , a nd t he e x tensive u se o f c l inker p lank ing i n med ieva l s h ipp ing s ou th o f S cand inav ia may h ave b een p ar t ly d ue t o t he f ac t t ha t t he n a t ive c e l t ic s h ipwr igh ts a lready u sed a f orm o f c l inker p lank ing i nt he ir own t rad i t ions. T he r ange o f ' ce l t ic ' s h ips a nd b oa ts o f R o man a nd med ieva l d a te h as b een f ound o n v ar ious s i tes f ro m L ake N eucha te l i n S w i tzer land t o t he mou th o f t he Rh ine i n t he N e ther lands . I n a dd i t ion t hey h ave b een i den t if ied a t An twerp , Bruges a nd P o m meroeu l i n B e lg ium , a s we l l a s i n L ondon ( Marsden , 1 976 ) a nd t he r ecogn i t ion o f t h is a pparen t ly i n ter l inked f am i ly o f e ar ly n or th-wes tern European t rad i t ions o pens u p n ew v istas i n o ur u nderstand ing o f l a ter d eve lopmen ts i n European s h ip t echno logy . I ndeed , a s E l l mers h as s hown , t he s ame b asic t rad i t ion s t i l l p robab ly l i ves amongs t c er ta in sma l l b oa ts i n at r ibu tary o f t he Rh ine ( E l l mers a nd P ir l ing 1 972 ) , a nd Is uspec t t ha t o n o ur own r iver , t he T ha mes , t he t rad i t iona l s w i mhead T ha mes Barge i s l i ke ly t o h ave b een a d escendan t o f t he c e l t ic t rad i t ion . T he v esse ls a re mos t ly l arge , s ha l low d raugh t , f la t-bo t to med c ra f t u sed o n i n land wa terways , p art icu lar ly o nt he Rh ine .
Bu t t he l a test r esearch s hows
t ha t t hey o ccur p robably a s f ar wes t a s t he S o mme i n F rance where i n 1 808 av esse l p robab ly w i th t h is s a me c ons truc t ion was f ound a t A bbev i l le ( Trau l le , 1 808 ) . A l though t he f irs t i den t i f ied f ind o ccurred i n 1 962 i n L ondon , i t was a lready k nown t ha t ac e l t ic s h ipbu i ld ing t rad i t ion h ad e x is ted b ecause i t was b r ie f ly d escr ibed b y J u lius C aesar i n t he f irs t c en tury B .C . C aesar was d escr ibing t he s h ips o f t he V ene t i t r ibe o f n or th-wes tern G au l , b u t t he l ack o f i n forma t ion i n h is d escr ip t ion mean t t ha t v ery l i t t le c ou ld b e j udged r egard ing t he s ign if icance o f t he t rad i t ion . I t was c lear , h owever , t ha t t he c e l t ic s h ips c ou ld b e l arge , f or C aesar f ound t he m v ery d i f f icu l t t o d e fea t f ro m h is sma l ler R o man war g a l leys . I t was o n ly a f ter i m mob i l ising t he V ene t i s h ips b y c u t t ing t he ir r igg ing t ha t t he R o mans managed t o c ap ture t he e ne my i n wha t i st he e ar l ies t r ecorded ma jor s ea b a t t le i n n or thern E urope . T he ir s h ips , C aesar wrote , were d i f feren t f ro m t he R o man s h ips o f t he Med i terranean a s t hey were h igh s ided , f la t b ot to med c raf t p rope l led o n ly b y l ea ther s a i ls , wh i le t he ir h u l ls were made f ro m t h ick p lanks a nd massive b ea ms h e ld t oge ther w i th i ron n a i ls a s t h ick a s a man 's t humb.
2 82
I ti s c lear t ha t t he s h ips o f t he V ene t i were d i f feren t f ro m t he s h ips o f t he S cand inav ians where y e t a nother t rad i t ion e x is ted f or i n t ha t a rea , a st he N ydam b oa t s hows , t he v esse ls h ad t h in o ver lapping p lanks a nd s lender r ibs , a nd a much more e legan t f or m .
A l though a s ub jec t ive c o mmen t w i th wh ich n o t
e veryone w i l l a gree , Id o t h ink i tf a ir t o s ay t ha t c o mpared w i th t he S cand in av ian t rad i t ion t he ' ce l t ic ' t rad i t ion , h owever we l l s u i ted t o t he e nv ironmen t i n wh ich t hey worked a nd t he j ob t hey h ad t o d o , was r a ther c rude - t he ir v esse ls b e ing g enera l ly more l i ke f l oa t ing b oxes a nd t ubs . Is ha l l r e turn t o t h is ma t ter l a ter a s Ib e l ieve i th as a p ar t icu lar s ign i f icance . Bu t f i rst t he t er m ' c e l t ic ' mus tb e e xp la ined b e fore t he c harac ter ist ics o f t he t rad i t ion a re d iscussed .
T he t er m i s f ar i ly l oose ly u sed , b u t i ti sb ased
o n t he f ac t t ha t t he a reas i n wh ich t hese v esse ls h ave b een f ound were p r i mar i ly o ccup ied b y C e l t ic p eop les , t hough i n t he L ow C oun tr ies a nd i n s ou th-eas tern Eng land t he B e lgae a re b e l ieved t o h ave b een o f mixed C e l t ic a nd G erman ic s tock . Mos t o f t he s o-ca l led ' ce l t ic ' s h ips h ave b een d iscovered i n t he B e lg ic r eg ion n ear t he mou th o f t he Rh ine a nd i n L ondon , t hough t he f inding o f t wo v esse ls i n t he p ure ly C e l t ic r eg ion o f L ake N eucha te l , S w i tzer land , d oes s treng then t he b e l ie f t ha t t hese were v esse ls b u i l t b y C e l t ic s h ipwr igh ts . I t i s r ea l ised t ha t t he t er m i sp erhaps n ot a s s u i tab le o r s pec i f ic a s s o me migh t w ish , t hough i td oes p rov ide a u se fu l umbre l la t er m t o s how t ha t t hese c ra f t a re d is t inc t ive ly d i f feren t f ro m t hose t ha t we t end t o c lass i fy u nder t he t er ms ' Scand inav ian ' a nd ‚Med i terranean .' T he b e l ie f t ha t ' ce l t ic ' i s as u i tab le t erm i s s treng thened b y t he d escr ip t ion o f t he s h ips o f t he V ene t i , ap ure ly C e l t ic t r ibe , wh ich c o mpares s o we l l w i th t he c harac ter ist ics o f t he B lack fr iars s h ip ; b u t i n v iew o f a l l t he u ncer ta in t ies t he t er m ' ce l t ic ' s hou ld b e u sed w i th a sma l l ' c '. P r ior t o 1 958 t he o n ly g enera l ly k nown d iscovery o f as h ip o f t he R o man p er iod i n n or thern Europe was t he mid-sec t ion o f t he h u l l o f a sma l l t rad ing v esse l f ound i n 1 910 i n L ondon o n t he s i te o f t he C oun ty H a l l , n ear Wes tm ins ter . N ow p reserved i n L ancas ter H ouse where i th as l ong b een we l l-known t o s h ip h is tor ians , t he s ign i f icance o f t h is f ind r ema ined u nknown u n t i l t he 1 930s . A t t ha t t ime d iscover ies i n L ake N em i i n I t a ly o f e nor mous s h ips s howed t ha t t he C oun ty H a l l s h ip was b u i l t a ccord ing t o t he c lassica l Med i terranean t rad t ion Bu t i nf ac t t h is was n ot t he f irs t p lank b u i l t c ra f t o f t he R o man p er iod t o h ave b een f ound a nd i den t i f ied i nn or thern E urope f or i n 1 899 a s im i lar ly c onstruc ted v esse l o f t he f irst c en tury A .D . h ad b een f ound a t Vech ten , n ear R o t terdam , i n t he N e ther lands . U n for tuna te ly t h is was p ub l ished i n a n o bscure Du tch a rchaeo log ica l r epor t ( Mu l ler , 1 895 ) a nd t he d iscovery r e mained u nknown u n t i l r ecen t ly . When i n t he 1 930s L ake N em i , af l ooded v o lcan ic c ra ter n ear R o me , was d ra ined t o e xpose t he t wo g rea t s unken R o man s h ips t ha t f or c en tur ies h ad b een k nown t o l i e t here , a rchaeo log is ts were a t l as t a b le t o h ave t he ir f i rst v iew o f c lassica l R o man s h ipbu i ld ing t echno logy a nd t hough t he f orms o f t he s h ips were n o t t hose o f s eagoing c ra f t t he ir b u i ld was s im i lar t o t ha t o f t he C oun ty H a l l s h ip . T h is d iscovery t hen t ended t o s treng then t he g enera l a ssump t ion t ha t t he u sua l s h ips t o b e s een i nt he n or thern p rov ince o f t he R o man emp ire were t he Med i terranean t ypes , i l lus tra t ions o f wh ich d a ting f ro m t he R o man p er iod h ave b een s o f requen t ly f ound i n t he Med i terranean b asin .
S im i lar ly t he s h ips
o f t he n or th h ave t ended t o b e t hough t o f a s e xc lus ive ly v esse ls o f t he S cand inav ian 2 83
t rad i t ion - s i mp ly b ecause v ery l i t t le was k nown a bou t t he C e l t ic t rad i t ion o f c en tra l a nd n or th western E urope .
T h is c lear c u t d iv ision was more a pparen t
t han r ea l wh i le t he C e l t ic t rad i t ion was u nknown , b u t j udg ing f ro m t he p reponde rance o f n a t ive c ra f t amongst t he d iscovered R o man v esse ls , t he ma jor p or ts o f n or thern Europe i n R o man t imes were p robab ly ma in ly f i l led w i th l oca l s h ips a nd b oa ts , w i th t he o ccasiona l t hough n o t r are v isi t o f a Med i terranean s h ip . E xc luding d ugou t c anoes , wh ich , d ur ing t he R o man p er iod h ave v ery l im i ted impor tance i n a ny th ing o ther t han l oca l e cono my a nd n o v a lue i n t he d eve lop men t o f s h ipbu i ld ing t echno logy b ecause c o mp lex p lank-bu i l t s h ips h ad a lready b een d eve loped b y t h is t ime , t here a re a t l eas t t h ir teen R o man s h ip a nd b oa t f inds o f C e l t ic t ype .
And f or t hese Ih ave p roposed t ha t t here a re
f our main t ypes B lack fr iars t ype , N ew Guy 's H ouse t ype , U trech t t ype , a nd Zwa m merda m t ype , t he n a mes b e ing t aken f ro m t he p lace where t he b es t e xamp le o f e ach t ype h as b een f ound
(r e ferences t o v ar ious t ypes a nd e x-
amp les d iscussed b e low a re i n Marsden , 1 976 ). T he B lack fr iars t ype was t he o n ly s eago ing v esse l o f t h is s er ies , t he e xa mp les b e ing B lack fr iars s h ip 1 o f t he s econd c en tury A .D ., f ro m L ondon , a nd t he Bruges b oa t wh ich was f ound i n 1 899 a nd h as b een r ecen t ly d a ted b y C arbon 1 4 t o A .D . 1 80 ± 8 0 .
T hese v esse ls p robab ly h ad n o k ee l , b u t h ad a
f la t p lank b u i l t b o t to m , a nd c arve l b u i l t s ides , t he p lanks b e ing n a i led t o mass ive r ibs o r f loor-t i mbers a nd n o t s o massive s ide f ra mes .
Ad is t inc t ive
f ea ture i s t he c ur ious ly s haped f loort i mber i n to wh ich t he mas t was s tepped . I ts ee ms t ha t t hese v esse ls were d eep t ub s haped c ra f t , i fo ne c an j udge f ro m t he B lack fr iars s h ip .
T he o r ig in o f t he t ype i s u ncer ta in b u t E .V . Wr igh t a nd
L . Basch ( Basch , 1 972 , p . 4 1-2 ) h ave d rawn a t ten t ion t o t he g rea t s im i lar i ty b e tween t he B lack fr iars s h ip a nd t he F err iby a nd Br igg b oa ts o f L a te Bronze Age - E ar ly I ron Age d a te .
T he who l ly p lank c onstruc t ion o f t he b o t to ms o f
t hese v esse ls p erhaps s uggests t ha t t hey may n o t h ave b een d eve loped f ro m t he d ugou t c anoe , b u t r a ther f ro m t he l og r af t . The N ew Guy 's H ouse t ype i s r epresen ted b y o n ly o ne f ind , ar iver b arge f ro m Guy 's H ospi ta l , n ear L ondon B r idge .
T h is was d iscovered i n 1 958 , a nd
much o f i ts t i l l r e ma ins t o b e e xcava ted - a t ask wh ich w i l l h ope fu l ly b e c arr ied o u t n ow t ha t ap rofessiona l a rchaeo log ica l o rgan isa t ion e x ists i n t he a rea .
Th is v esse l was a lso a t ubl ike c ra f t , t he b ea m t o l eng th r a t io b e ing
v ery g rea t a nd i th ad c arve l b u i l t s ides a nd a f la t b ot to m , a nd i ts ee ms c lear t ha t u n l ike t he R h ine b arges d escr ibed b e low , i t s b o t to m c urved a round t o i t s s ides .
Un l ike t he s h ips o f B lack fr iars t ype whose p lace o f c onstruc t ion c an-
n o t b e a ccura te ly e stabl ished d ue t o t hese b e ing s eagoing s h ips , t he N ew G uy 's H ouse b oa t was a s ha l low d raugh t r iver c ra f t t ha t must h ave b een b u i l t o n t he Tha mes . The Zwa m merda m t ype a lso was a r iver c ra f t whose f la t p lank b u i l t b o t to m , a nd l ow s ides were c onnec ted a t t he c h ine b y ap lank c u t t o a n L -s hape i n s ec t ion .
Vesse ls o f t h is t ype c ou ld b e t ru ly e nor mous , t he l arges t k nown
b e ing 3 4 m l ong .
Exa mp les o f t h is t ype d a t ing f ro m t he R o man p er iod a re
Zwa m merda m s h ips 2 , 4a nd 6 , ( Ne ther lands ) t he Kape l Avazaa th s h ip ( Ne ther lands ) , t he Beva ix a nd Yverdon s h ips ( Sw i tzer land ) , p robab ly t he Dru ten b oa t ( Ne ther lands ) , t he P o m meroeu l b oa t 1( Be lg iu m ), a nd p robab ly t he Abbev i l le b oa t ( France ) . 2 84
T he o r ig in o f t he Zwa m merda m t ype i sp resumab ly t he d ugou t c anoe , f or t he L -p lanks a re r e mnan ts o f t he e ar ly d ugou t o r ig in , t he d ugou t h aving b een s p i l t l eng thways t o a l low p lanks t o b e i nser ted t o f orm a w ider f la t b o t to m . T he U trech t t ype a lso n o d oub t d eve loped f ro m t he d ugou t c anoe f or i t s b o t to m was f or med o f al arge d ugou t t he s ides o f wh ich were b u i l t u pwards w i th p lank ing .
On ly o ne R o man e xa mp les o f t h is t ype a s b een f ound , t h is
b e ing Zwa m merda m s h ip 3f ound i n t he N e ther lands . S o me o f t hese n a t ive t ypes c er ta in ly c on tinued i n u se i n to t he Midd le Ages , t he b oxl ike Zwa m merdam t ype r e ma in ing b u t h av ing t he s ing le L - s haped p lank r ep laced b y t wo p lanks j o ined t o f or m n ear ly a r igh t a ng le . Two e xamp les o f t h is t ype h ave b een f ound d a ting f ro m t he M idd le Ages , ab oa t f ro m Kre fe ld i n G ermany ( E l l mers a nd P in i ng , 1 972 ) a nd a nother v esse l f ound i n U trech t i n 1 974 ( Hocks tra , 1 975 ) . I ti s p erhaps f ro m a v ar ia t ion o f t h is t ype t ha t t he t rad i t iona l s w i m-head T ha mes Barge was d eve loped , a nd t hese c ont inen ta l d iscover ies u nder l ine h ow v ery i mpor tan t i ti s t o r ecord modern t rad i t iona l b oa t t ypes a nd t he ir c onstruc t ion .
E xa mp les o f t he s w i m-head
Tha mes B arge h ave n o t e x is ted f or a l ong t ime , b u t e very o ppor tun i ty s hou ld b e s iezed t o e xcava te o ne s hou ld i tb e f ound a s i ndeed t hree d a t ing f ro m t he e igh teen th c en tury were f ound a t B a t tersea o n t he T ha mes s evera l y ears a go . T he U trech t t ype a lso c on t inued i n u se i n to a t l eas t t he e ar ly Med ieva l p er iod - t o t he 1 1 th o r 1 2 th c en tur ies - t hree e xa mp les o f t h is t ype h av ing b een f ound . T he f irst d iscovery o ccurred a t U trech t i n 1 930 ( where i ti s s t i l l p res erved i nt he C en tra l Museum ) , t he n ex t a t An twerp i n 1 905 ( Ph i l ipsen , 1 965 ) a nd t he l as t a t U trech t i n 1 974 ( Hoekstra , 1 975 ) . T he f a ir ly c rude a nd s i mp le f orm a nd c onstruc t ion o f t hese C e l t ic v esse ls i s , Ib e l ieve , ak ey f ac tor i n u nders tanding t he ir s ign i f icance i n R o man t imes , a s i s a lso s uggested b y ad e ta i led s tudy o f t he c ho ice a nd u se o f t imber f ro m wh ich t he B lack fr iars R o man s h ip was b u i l t . Th is i s a n a spec t wh ich was n ot c onsidered i n my r epor t o n t he B lack fr iars s h ip a nd i ndeed t he f ac t t ha t t here i s an eed f or t h is d iscussion a t a l l i s a n i nd ica t ion o f t he g rea ter k now ledge a nd u nderstand ing wh ich i s n owadays r equ ired i n t he s tudy o f e ar ly s h ips . I n t h is p aper Iam b r ie f ly c ons ider ing t he c hoice o f t imber a nd t he me thods u sed i n s haping t he m . Bu t f irs t l e t me s ay a f ew words a bou t t he c o mp le ted B lack fr iars s h ip . S he was q u i te a l arge v esse l , b u i l t e n t ire ly o f o ak , e s t i ma ted o r ig ina l ly t o h ave b een a bou t 5 5 f t . ( 1 6 .8 m ) l ong a nd a bou t 2 1 f t . ( 6 .4 m ) b road w i th a d ep th am idsh ips o f more t han 7 f t . ( 2 .1 m ) . T he c arve l b u i l t s ides me t t he f a ir ly f la t c arve l b u i l t b o t to m t o f orm a n a ng le o r c h ine o f 3 0-35° . T here was n o k ee l , b u t i nstead t wo b road l ong i tud ina l p lanks e ach 3 i n ( 0 .076 m) t h ick . The b ot to m p lanks a nd t he f i rs t s trake a bove t he c hines were n a i led t o massive f loort i mbers , wh i le t he s ide p lanks were n a i led t o sma l ler s ide f ra mes , t he b o t to m e nds o f wh ich were a lso f astened t o t he f irs t s trake a bove e ach c h ine . T he e nds o f t he s h ip were n o t t oo we l l p reserved t hough t here i s c lear e v idence t ha t t hey were p oin ted .
P ropu lsion was b y means o f p robably a
s quare s a i l o n a mas t s tepped i n to a s pec ia l ly s haped f l oor-t imber , i n wh ich ac o in o f t he Emperor D om i t ian h ad b een p laced f or l uck , a bou t o neth ird o f t he l eng th o f t he s h ip f ro m t he b ow .
N o e v idence o f t he s teer ing a rrange men t
2 85
was f ound , b u t t h is was n o d oub t a ch ieved b y u s ing o ne o r t wo s teer ing o ars. T he who le c ons truct ion was h eavy , w ith t h ick b road p lanks a nd mass ive f l oort i mbers wh ich h ad c lear ly b een c u t f ro m s ubs tan t ia l o ak t rees . Bu t a l though a f a ir ly a ccura te s ke tched r ecord was made i n 1 962 o f t he t ree-r ing p a t terns s hown i n t he s ec t ions a cross t he t imbers , Id id n o t d iscuss t he ir s ign i f icance i n my r epor t o n t he s h ip p ub l ished i n 1 965 .
I ti s t hanks t o
t he more r ecen t work o n o ther s h ips , p ar t icu lar ly b y O le C rum l in-Pedersen o f t he V ik ing s h ip museu m a t R osk i lde a nd o f S ean McGra i l o f t he N a t iona l Mar i t i me Museu m a t G reenw ich t ha t t hese ma t ters h ave b een h igh l igh ted a nd s hown t o b e i mpor tan t .
I n f ac t , as tudy o f t he o r ig ina l c u t t ing o f l ogs t o make
r ibs a nd p lanks w i l l s oon b e made when d e ta i led s tud ies b eg in o f t he s evera l S axon a nd Med ieva l b oa t r e mains r ecen t ly f ound i n L ondon b y t he D epar t men t o f Urban Archaeo logy , o f t he Museu m o f L ondon . The marve l lous p ho tograph i n t he N a t iona l Mar i t i me Museum 's monog raph o n t he G okstad f aer ing , o f b oa t-bu i lder H arold K i mber c hoosing a n o ak l og f ro m a g rea t p i le f or b u i ld ing a r ep l ica o f t he V ik ing b oa t , e choes t he f irst s tep i n b u i ld ing a s h ip t ha t h appened c oun t less t imes d own t he a ges ( McGra i l 1 974 : 1 5 ) . The b ot to m p lanks i n t he B lack fr iars s h ip were a s much a s 2f t . 7 in . ( 0 .79 m ) w ide a nd c lear ly o f c onsiderable l eng th ( cer ta in ly more t han 1 8 f t , 5 .5 m) , a nd a s tudy o f t he t ree-r ing a l ign men ts a cross t he p lanks , wh ich were s ec t ioned i n s evera l p laces , e nab les t he a pprox i ma te c en tre o f t he t rees f ro m wh ich t hey were c u t t o b e j udged .
I ti s c lear f ro m t hese t ha t t he l og o r l ogs
h ad b een c u t t angen t ia l ly t o f or m t he p lank ing , a nd b ecause t he ' Ce l t ic
s h ip-
b u i lding me thods were r ea l ly q u i te p r im i t ive Is usupec t t ha t t he l ogs were most l ike ly s awn i n t he s i mp le ' t hrough-andthrough ' t echn ique ( McGra i l 1 974 , p . 4 2-3 ) .
F or tuna te ly , ac are fu l s tudy o f t he p lanks i n s o me o f t he
r ecen t s h ip d iscover ies , s uch a s t hose a t Zwa m merda m i n t he N e ther lands , c ou ld e s tab l ish t he p lank c u t t ing t echn ique w i th more c er ta in ty. N ever the less , i n o rder t o make t he w ides t p lanks i n t he b o t to m o f t he B lack fr iars s h ip a n o ak t ree r ough ly w i th a min i mu m d ia me ter o f 7 f t . 6 in . ( 2 .3 m) h ad t o b e u sed . Na tura l ly t h is i s av ery r ough e st i ma te , b u t i td oes g ive s o me i nd ica t ion o f t he s ize o f t ree i nvolved ; a nd a l though i ti s v ery d i f f icu l t t o j udge t he a ge o f s uch a t ree , Iam a dv ised t ha t i tc ou ld h ave b een a pprox i ma te ly 2 00-300 y ears o ld when i t was c u t d own t o b u i ld t he s h ip , p robab ly i n t he e ar ly 2 nd c en tury A .D . T he r i bs a nd s te mpos t w ere c u t f ro m sma l ler l ogs , t he f l oort i mber h av ing ,most ly b een c u t f ro m who le l ogs , wh i le s evera l o f t he sma l l s ide f ra mes h ad e v iden t ly b een c u t f ro m t he s a me l og . A lthough t he f l oor-t i mbers c ou ld n o t b e s ec tioned t o a ccura te ly r ecord t he t ree r ing p a t terns , t he s izes o f t he o r ig ina l l ogs were e st i ma ted b o th f ro m wha t c ou ld b e s een o f t he r ings a nd f ro m t he e x ten t o f t he l igh ter , s o f ter s apwood p reserved i n t he r ibs , a s we l l a s f ro m p ar ts o f t he e x terna l c urva ture o f t he l og ( t he b ark h av ing b een r e moved ) wh ich was a lso p reserved .
Thus i ti s c lear t ha t t he t ree t runks f ro m wh ich t he
f loor-t i mbers were c u t were v ery a pprox i ma te ly b e tween 1 2 i n . ( 0 .3 m) a nd 4 0 i n . ( 1 .01 m ) i n d ia me ter .
And a lso i ti s c lear t ha t most o f t he s l igh t ly
U -s haped f loor-t i mbers h ad b een c u t f ro m f a ir ly s tra igh t t reetrunks , s o t ha t when t he l og was l y ing o n t he g round t he c en tra l p ar t o f t he r ib , t he
2 86
l owes t p oin t o f t he U -shape , h ad b een c u t f ro m t he b ot to m o f al og t o a l low t he h igher e nds o f t he r ib t o b e c u t f ro m t he t op o f t he l og . T here i s l i t t le d irec t ,ev idence t o s how h ow t he p lanks w ere c u t a nd t he r ibs s haped a s n o d is t inc t ive marks l e f t b y t he c u t t ing t oo ls w ere o bserved. I ts ee ms mos t l ikely t ha t av ery l arge s aw ( a t l eas t 1 f t . , 3 .35 m l ong ) was r equ ired t o c u t d own t he t rees a nd t hen t o c u t t he p lanks f ro m t he l ogs ; wh i le t he c urved r ibs w ere p resu mab ly a dzed o r a xed i n to s hape. p lanks w ere h e ld t o e ach o ther b y l ong c lenched i ron n a i ls ;
T he r ibs a nd a nd s o t hat t hese
c ou ld b e d r iven t hrough t he f l oor-t i mbers h o les P i -i n . ( 0 .02 m ) i n d ia meter w ere d r i l led o u t , p resu mab ly b y u s ing a s poon b i t , a nd a n o ak p eg w as i nsert ed b efore t he i ron n a i l w as d r iven i n . T he t imbers o f t he B lack fr iars s h ip i nd ica te t he g rea t a ge a nd e x ten t o f t he o ak f ores ts i n n or thern Europe d ur ing t he f i rs t a nd s econd c en tur ies A .D. T hese ' Cel t ic ' s h ips i l lus tra te a n a t ive s h ipbu i ld ing t rad it ion o f n or thwestern Europe wh ich , n o d oub t , e x isted b efore t he Ro man i nvas ions. Pr ior t o t hose i nvas ions when t he e cono my o f t he r eg ion was o f v ery l im ited e x ten t i ti s l ike ly t ha t t he n a t ive s h ips ,
r ef lect ing t he ir p r im it ive c ons truc-
t i on w ere g enera l ly o f sma l l s ize a nd l im ited n u mber .
With t he c om ing
o f t he R o mans t here s udden ly a rr ived a s oph ist ica ted e cono my r equ ir ing a v ast ly i ncreased wa terborne t raf f ic .
A l though t he Med i terranean t radi t ion
was i n troduced i n to t he n or th b y t he R o mans a s s hown b y t he C oun ty H a l l , Vech ten a nd Zwa mmerdam 2 a s h ips , t he n a t ive s h ipwr igh ts c ou ld h ave h ad l i t t le t ime t o l earn t hese n ew t echn iques , a nd i ns tead , j udg ing f ro m t he n umbers f ound , i ti s l ike ly t ha t v esse ls o f t he ir n a t ive t rad i t ion were much more c om mon ly u sed . I ndeed i ti sp robable t ha t t hey h ad l i t t le t ime t o r e fine t he ir own c onserva t ive c ons truc t ion t echn iques , a nd i ns tead , v ery b ig s h ips w i th s i mple c onstruc t ions a nd f orm , more s u i ted t o sma l ler v esse ls , were b u i l t a ccording t o t he p r im i t ive o ld me thods , a nd i ti s t h is t ha t we s ee b o th i n t he B lack fr iars s h ip a nd e ven more c lear ly p ar t icu lar ly i n mos t o f t he Zwam merdam s h ips o f R o man d a te r ecen t ly f ound n ear R o t terda m . F ina l ly Iwou ld l ike t o a dd t ha t t he S c ience Museum a nd t he Museum o f L ondon t hrough t he i n i t ia t ive o f Bas i l B a the o f t he f or mer museum mos t c aref u l ly h ad v ery e xac t s ca le mode ls made o f t he r e ma ins o f t he f orward p ar t o f t he B lack fr iars s h ip ; wh i le more r ecen t ly t he R o man g a l lery o f t he Museu m o f L ondon , t o b e o pened a t t he e nd o f 1 976 , i s f ea tur ing t h is s h ip n o t o n ly w i th ap ar t ly r econs truc ted mode l o f t he v esse l a t al arge s ca le , b u t a lso w i th a f u l l s ize p ar t ly r econs truc ted c ross-sec t ion o f t he s h ip i ncorpora t ing b o th t he o r ig ina l t imber e le men ts o f t he v esse l a nd a ccura te r ep l icas o f t hose p ar ts o f t he h u l l wh ich were b ad ly d a maged o n d ry ing o u t .
2 87
REFERENCES
Arnold , B ., 1 974 . ' La b arque g a l lo-ro ma ine d e l a b a le d e Beva ix '
C ah iers
Fre jus) , i i : 1 33-50 . d 'archeolog ie s ubaqa t ique ( Basch , L ., 1 972 . ' Anc ien t wrecks a nd t he a rchaeology o f s h ips ' I n terna t iona l J ourna l o f Nau t ica l Archaeo logy ( London )
1 : 1 -58 .
Eg lof f , M., 1 974. ' La b arque d e Bevaix , e pave g a l lo-ro ma ine d u l ac d e N euchä te l '.
He lve t ia Archaeolog ica ( Base l ) , 1 9/20 : 8 2-91.
E l l mers , D ., 1 969 . ' Ke ltischer s ch i f fbau '. Ger man ischen Z en tra l museu ms ,
J ahrbuch d es R i t im isch-
( Ma inz ) , 7 3-122 .
E l l mers , D ., a nd P ining , R ., 1 972 . ' Ein mi t te la l ter l iches s chi f f a us d em Rhe in '.
D ie Hei ma t , Z e i tschr i f t f ür n iedrrhe ins k u l tur - u nd h eima tp f lege ,
( Kre fe ld ) ,
4 3 : 4 5-48 .
H ockstra , T ., 1 975 . N ote o n a nc ien t s h ips f ound a t U trech t i n I n terna tiona l J ourna l o f Nau tica l Archaeo logy ( London ) , 4 : 3 90-391. Marsden , P ., 1 966.
A R o man s h ip f ro m B lack fr iars , L ondon . Gu i ldha l l
Museu m , L ondon . V I arsden , P ., 1 976. ' A b oa t o f t he Ro man p er iod f ound a t Bruges , Be lg ium , i n 1 899 , a nd r ela ted t ypes ' , I n terna t iona l J ourna l o f Nau tica l Archaeology ( London ), 5 : 2 3-55 . McGra i l , S ., 1 974.
The Bu ild ing a nd Tr ia ls o f t he Rep l ica o f a n Anc ien t Boat :
The Gokstad Faer ing , Par t 1 , Bu i ld ing t he r ep l ica .
Mar i t i me Monographs
a nd Repor ts N o . 1 1. Na tiona l Mar i t i me Museu m , Greenw ich . Mu l ler , S ., 1 895 .
Verslag v an h e t v erhande l . le i n d e a lge meene v ergader ing
h e t Prov inciaa l U trech tsch G enoo tschap v an Kunsten e n We tenschappen . U trech t , 1 895 . Ph i lipsen , J ., 1 965 . ' The U trech t s h ip ' , The Mar iner 's Mirror 5 1: 3 5-46 . Trau lle , M., 1 809.
Le t tre a dressee a M. Mongez , Me mbre d e l ' Insti tu t ,
p ar M. Trau l le .... s ur l es d ebr is d 'un b a teau d e terre d ens l e l evees d e l a S o m me . Weerd , M.
Par is , 1 809 .
d e a nd Haa lebos , J . K., 1 973.
S piege l H istor iae l ,
' S chepen v oor h e t o pscheppen ' .
( Bussum ) , J u ly-Augus t : 3 86-97.
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2 2
BOAT-ARCHAEOLOGY OF THE THAMES Dav id S turdy S u m mary
T he T ha mes , l i ke e very o ther ma jor r iver , h as g rea t p ossib i l i t ies f or r esearch a bou t a nd d iscover ies o f e ar ly b oa ts ;
af l ex ib le a nd
d e l ibera te a pproach w i l lp roduce a wea l th o f i n for ma t ion . P ara l le l a pproaches a re s ugges ted : b ackwards f ro m t he d ocu men tary ma ter ia l a nd s ideways f ro m t he e v idence o f r iverside s i tes . F our t rad i t iona l t ypes o f work ing c raf t f ro m t he R iver Thames a bove L ondon B r idge a re d escr ibed .
T h is p aper o u t l ines t he p o ten t ia l f or a p rogram me o f p urpose fu l r esearch i n to t he a rchaeo logy o f t he b oa t a long t he Tha mes . Impor tan t work h as b een d one i n t he t i da l wa ters a nd e spec ia l ly i n L ondon , b u t more work i s g rea t ly n eeded o n t he u pper wa ters o ft he r iver . N o s a t isfac tory b oa t-f ind h as y e t b een r ecorded a long 1 50 k i lo me tres o f n av igab le r iver b e tween S ta ines a nd L ech lade . I mpor tan t f i nds a re c onstan t ly b e ing made i n d redg ing t he r iver , a nd b oa ts mus t s ooner o r l a ter b e r ecovered i n d a ted c on tex ts w i th a ssoc ia ted o b jec ts . C reeks a nd a bandoned s ide-channe ls a re t he most l i ke ly t o c on ta in b oa tr e ma ins i n s ubs tan t ia l f or m : b y c ons ider ing a rchaeolog ica l s i tes o n l and we c an i den t i fy b o th a reas o f g enera l i n teres t f or s pec i f ic p er iods a nd k ey-areas o f o u ts tand ing i mpor tance f or p ossib le e ar ly b oa t-f inds ( F ig . 2 2.1 a nd 2 ) . T he a nces try a nd r e la t ions o f t he b oa ts k nown i n h is tor ica l t imes w i l l b e c lar i f ied o n ly b y t he r ecovery a nd s tudy o f a c tua l p ieces b y e xcava t ion . On ly w i th a s er ies o f d a ted e xa mp les c an we d iscuss p ossib le c on t inu i ty o f t rad it i on f ro m t he p rov inc ia l-Ro man B lack fr iars s h ip t o t he r iver-barge o f E l izab e than p ic tures ; whe ther t he wherry h as a S cand inav ian o r ig in ; o r wha t t he p un t c a me f ro m . I ti s , h owever , v a luab le t o d escr ibe t he t rad i t iona l b oa tt ypes o f t he T ha mes a nd d e f ine t he c hanges wh ich t hey u nderwen t i n r easonably we l l-documen ted h istor ica l t imes . The v ery c onsiderab le c hanges o f t ype , s hape a nd f unc t ion wh ich c an b e d iscerned r em ind u s t ha t e ar lier p er iods p robab ly s aw e qua l ly c o mp le te c hange a nd g rea t d eve lop men t . T h is p aper d ea ls w i th t he e veryday w ork ing c ra f t o f t he r iver a bove L ondon B r idge . I td oes n o t d iscuss e i ther t he s ta te-barges o r t he s a i lingc raf t o f t he e s tuary , s uch a s Bark ing-s macks , Tha mes s a i l ing-barges o r t he e ar l ier h oys .
2 89
R IVER THA MES AT OXF ORD L a te S axon t ime s\
b u i lt -up a rea
F ig . 2 2.1
F ormer c hanne ls o f t he R iver Tha mes a t Ox ford .
THE WHERRY , SK IFF OR RO W ING-BOAT The mos t c o m mon sma l l c raf t o n t he T ha mes a t L ondon was t he wherry , a s f am i l iar a nd a s f ree ly u sed a s t he t ax i t oday . The word , h ere a pp l ied t o al igh t r ow ing b oa t , i s o f o bscure o r ig in a nd i s f irst r ecorded i n A .D . 1 443 . The l a ter u se o f ' wherry ' t o mean a l arge b argel ike v esse l h as s urv ived o n t he N or fo lk b roads . Ac lear e ar ly r epresen ta t ion o f a bou t A .D . 1 500 i s g iven i n t he we l l k nown v iew o f t he T ower d rawn b y aF le m ish a r t is t i n Eng land f or t he P oe ms o f C har les Duke o f Or leans .
Th is s hows t wo b oa ts w i th h igh b ow a nd s tern , e ach
w i th a g roup o f p assengers i n t he s tern a nd t wo o ars men i n t he b ows p u l l ing a cross t he r iver t o t he C usto m H ouse . I ti s c lear t ha t t hese c raf t c hanged c onsiderab ly i n a bou t A .D . 1 535 .
An
Ac t o f 1 555 r e fers t o ' boa ts a nd wherr ies ' o f ' t he o ld s ubstan t ia l s or t , a nd s ure mak ing o f b oa ts wh ich was u sed b e fore t he s pace o f t wen ty y ears t hen p as t ' . T he n ew k ind o f b oa t was ' so l i t t le a nd sma l l i n p ropor t ion a nd s o s tra igh t a nd n arrow i n t he b o t to m ' a s t o b e d angerous .
The Ac t p rescr ibed t ha t
wherr ies s hou ld b e 2 2 .1 f t . i n l eng th a nd L q f t . i n b read th . V iews o f L ondon i n t he mid 1 6th c en tury s how wherr ies b o th w i th h igh b ow a nd s tern , p resumab ly t he s o l id o lder s or t , a nd w i th a l ow p ro f i le , p resu mably t he n ew h andy p a t tern . T h is d eve lop men t i s we l l c on f irmed b y b o th d ocu men ts a nd i l lustra t ions . The wherry 's l a ter c hanges i n i t s d eve lop men t i n to t he modern r ow ing-boa t n eed b oth more r eseach a nd a c tua l e xa mples t o s tudy .
The e ar l ies t s urv iv-
i ng e xa mp les , t he d eep b lu f f-prowed G ravesend Wherry o f 1 888 , t he p leasures k i f f o f 1 905 ( bo th a t G reenw ich ) a nd t he Ox ford r ac ing e igh t o f 1 829 ( i n t he S c ience Museum ) d i f fer g rea t ly . T he Wherr ies s hown i n t he ir t housands o n 1 7th a nd 1 8th c en tury i l lustrat i ons w ere d oub le-ended a nd l acked r udders ;
t wo o ars men a nd u p t o s ix
p assengers a re g enera l ly s hown , a nd o ccas iona l ly a sma l l s pr it-sa i l.
T he
e xa mp le o f a' Tha mes wherry ' whose l ines w ere p ub l ished i n 1 768 was 2 6 f t . l ong , r a ther l arger t han t he 1 555 s tandard.
T hey s ee m t o h ave b een f i t ted
w ith r udders o n av est ig ia l t ranso m o n ly a f ter a bout A .D. 1 860.
By t h is t ime
t he e xpans ion o f L ondon a nd t he b u i ld ing o f many b r idges a cross t he r iver mean t t hat t hey w ere n o l onger t he u n iversa l way o f g et t ing a bou t t he t own . For t h is t he Hanso m Cab h ad s upp lan ted t he wherry .
T hey h ad b eco me f am ily
p leasure-boa ts a nd t he o ld s k il ls o f s teer ing t he m w ith t he o ars w e l l u p t owards t he b ows was n o l onger p ract ised. T he P e ter-boa t u sed f or f i sh ing i n t he e stuary a nd u pr iver t o Bren tford i n t he e ar ly 1 9 th c en tury p resen ts p rob le ms .
Th is d is t inc t ive b road t hwar t less
c raf t i s v ery u nco m mon o n 1 7th a nd 1 8 th c en tury i l lus tra t ions , b u t af ew c an b e f ound .
T hey b ear a marked s im i lar i ty t o t he Du tch ' Kuh boo t ' f ro m t he
n or th o f t he Zu ider-See a nd t o t he ' Aa l jo l le ' o f t he C ranz am E lbe n ear H a mburg , a n a rea r ec lai med a nd c o lon ised b y Du tch i mm igran ts i n t he 1 5 th a nd 1 6th c en tur ies .
H ow f ar t he P e ter-boa t i s d er ived f ro m t he wherry , a nd h ow f ar
i ti s a n a c tua l Du tch t ype b rough t o ver t o work o n r ec la ma t ion o f t he Tha mes i s o bscure .
2 92
F ig. 2 2.3
Boats a t t he mou th o f t he F leet R iver , L ondon i n 1 676. d eta i l f ro m Og i lby a nd Morgan 's map.
A
Hoys c arr ied p assengers
a nd c argo i n t he o uter waters o f t he Tha mes Estuary.
L igh ters
c arr ied c argo , a nd Wherr ies p assengers , o n t he T ha mes a t London.
Western b arges c arr ied c argo u p-r iver.
T he Hoys
measured 5 5 t o 6 0 f t ., L ighters 4 0 t o 5 0 f t ., Wherr ies ( much e xaggera ted i n t he f oreground ) n ot more t han 3 0 f t , a nd Western b arges 7 5 t o 1 00 f t .
THE L IGHTER A s c harac ter ist ic a s t he wherry , wh ich was t o b e f ound a l l a long t he r iver , t he l igh ter h as a lways b een r es tr ic ted t o L ondon wa ters . o f t he l igh ter i s o bscure .
T he o r ig in
T he word f irst o ccurs i n A .D . 1 372 a nd means ,
o bv iously , av esse l i n to wh ich a s h ip i s u n loaded o r l igh tened .
Most v esse ls
o f t h is p eriod were sma l l e nough t o l i e o n t he mud a ga inst a r ivers ide whar f , a nd i ts ee ms u n l ike ly t ha t l i gh ters d eve loped t he ir f or m a nd way o f u se u n t i l t he g rea t e xpansion i n t he s ize o f s h ips i n t he l a te 1 5 th c en tury . I ta lso s ee ms u n l ike ly t ha t l igh ters were n u merous u n t i l t he e ar ly o r mid 1 7th c en tury . Wyngaerde 's v iew o f C . 1 550 d oes n o t s how a ny r ecogn iseab le l igh ters a nd Braun a nd H oe fnag le i n C . 1 560 s how o n ly a f ew p ossib le e xa mp les l y ing s ing ly a t b uoys .
T he ir wherr ies a re much o versized a nd may p erhaps b e
c on fused w i th l i gh ters . P ossib ly t oo , l igh ters o f t he l a te 1 6th c en tury were n o more t han 3 0 f t l ong , s carce ly l arger a l though r a ther d eeper t han wherr ies . I n t he l a te 1 7th c en tury , h owever , t he l igh ter c an b e c lear ly d is t ingu ished f ro m t he wherry .
T he e ar ly l igh ters o f t h is p er iod were q u i te u n l ike t he
s wi m-headed s lab-sided l igh ter o f t oday . Many r epresen ta t ives s how t he m a s d oub le-ended b oa t-shaped c ra f t b e tween 4 0 a nd 5 0 f ee t l ong , w i th a we l l marked s heer r is ing t o f a ir ly b lun t s te ms .
T hey were w i thou t mas t o r r udder ,
worked f ro m e i ther e nd w i th s weeps a nd mus t h ave h and led v ery d i f feren t ly f ro m modern l i gh ters.
Wi th t he ir r ounded c ross-sec t ion a nd v ir tual a bsence
o f k ee l , t o j udge f ro m t he s o l i tary e xa mp le f ound b y P au l 's S ta irs ( Marsden , 1 971 ) , t hey h ad a c tua l ly t o b e r owed a cross t he s trea m ( F ig . 2 2.3 ).
T he V ic-
t or ian l igh ter man c ou ld make a c rude ' aero fo i l ' w i th t he s ide o f h is l igh ter a nd h is s weep a nd ' l i f t ' h is much h eav ier v esse l a cross t he t ide . F or p rog ress a long t he r iver b o th s or ts o f l igh ter d epended o n wa i t ing f or a t ide , u n t i l t ug-drawn t ra ins o f l igh ters b eca me c o m monp lace i n r ecen t t imes. T he c hange f ro m sma l l b oa t-shaped l igh ters t o l arger p un tform o nes s ee ms t o h ave o ccurred i n t he 1 820s , a bou t ag enera t ion a f ter a s im i lar c hange f ro m c argo-pun ts h ad h appened i n r iver-barges .
T h is makes i td i f-
f icu l t t o a ccep t t he c onven t iona l e xp lana t ion t ha t t he T ha mes s a i l ing-barge i n i t s e ar ly s wi m-headed f or m d eve loped f ro m t he s wi m-headed l igh ter . B o th a ppear i n e ngrav ings a nd p ic tures a t a bou t t he s a me t ime , a nd t he o r ig in o f t he T ha mes b arge n eeds more i nvest iga t ion . T he H u mber k ee l , a part f ro m b e ing r igged , b ears a c onsiderab le r ese mb lance t o t he e ar ly T ha mes l igh ter . THE R IVER BARGE T he T ha mes r iver-barge o f t he 1 6th , 1 7th a nd 1 8 th c en tur ies i s ad ist inct ive t ype , al arge s ha l low v esse l 7 5 t o 1 00 f ee t l ong w i th l i t t le r ise t o b ow a nd s tern , al ong s ha l low r udder , as ing le c en tra l mast f or t owing o r as quare s a i l , a nd a c ab in o f h ooped c anvas i n t he s tern .
T hey a re s hown u nder e very
p ossib le f or m o f p ropu lsion . I n t he 1 560s Braun a nd H ogenberg 's v iew ( 1572 ) h as t wo r unning d ownstrea m p ast West m inster u nder s a i l , o ne w i th f our o ars o u t .
L a ter v iews s how t he m b e ing p o led o r t owed b y s tr ings o f men o r h orses.
T en o r t we lve h orses were n eeded t o p u l l u pstrea m a nd s even d ownstrea m i n a n a ccoun t o f 1 775 .
T hey h ad a c rew o f t hree t o s ix men a nd a l arger c argo
2 94
c apac i ty t han many s eagoing v esse ls o f t he p er iod .
I n 1 775 v esse ls o f 1 40
t ons were s a id t o b e a b le t o g o u p t o Wa l l ing ford a nd 7 0tonners t o L ech lade . Wr i t ing i n a bou t A .D . 1 700-1720 D e foe s ays o f R eading : ' The ir c h ie f t rade i sb y wa ter-nav iga t ion t o a nd f ro m L ondon ...., p ar t icu lar ly c oa ls , s a l t , g rocery wares , t obacco , o y ls , a nd a l l h eavy g ood .
T hey s end f ro m h ence t o
L ondon b y t hese b arges , v ery g rea t q uan t i t ies o f ma l t , a nd mea l , a nd t hese a re t he t wo p r incipa l a r t ic les o f t he ir l oad ings , o f wh ich , s o l arge a re t hose b arges t ha t s o me o f t he m , a s Iwas t o ld , b r ing a t housand o r t we lve h undred q uar ters o f ma l t a t at ime , wh ich a ccord ing t o t he o rdinary c o mpu ta t ion o f t onnage i n t he f re igh t o f o ther v esse ls , i s f ro m a h undred , t o ah undred a nd t wen ty t on , d ead we igh t '. O f L ondon h e s ays ' t he v esse ls wh ich b r ing t h is ma l t a nd mea l t o Queen H i th , a re wor th t he o bserva t ion o f a ny s tranger t ha t u nderstands s uch t h ings . T hey a re r e markab le f or t he l eng th o f t he v esse l , a nd t he b urden t hey c arry , a nd y e t t he l i t t le wa ter t hey d raw ; i n a word , s o me o f t hose b arges c arry a bove a t housand q uar ter o f ma l t a t at ime , a nd y e t d o n ot d raw t wo f oot o f wa ter .
S o me o f t hese l arge b arges c o me a s f ar a s f ro m Abingdon .'
T he c i ty wa ter-ba li f f e s t i ma ted i n 1 746 ' t ha t 3 00 Barges p ass a nd r epass a t l eas t 6 t i mes i n ay ear '.
Many o f t he ir c argoes must h ave b een v ery sma l l ,
s ince o n ly 5 6 ,000 t ons o f c argo was r ecorded a s p assing Mar low i n 1 767. T h is c ou ld h ave b een c arr ied o n o n ly a t h ird t he n umber o f v oyages e st i ma ted . H owever a l l t hese Georg ian s ta t is t ics s ee m t horough ly v ague a nd mudd led , a nd D e foe 's c apac i ty- measures s ee m t o g ive d oub le h is t onnage .
T he r iver-
b arge o f t h is t ype , whose o r ig ins may g o b ack t o med ieva l o r e ven Ang loS axon t imes , d isappeared i n t he l a te 1 8 th c en tury .
F or a t ime i n a bou t A .D.
1 770-1800 p ic tures s how t he r iver-barges w i th much g rea ter s heer a nd t hen f ro m a bou t A .D . 1 800 b ig s w i m-headed c argo-pun ts r ep lace b oa t-shaped b arges. c o mp le te ly o n t he u pper T ha mes b u t t he o lder f or m r e ma ined o n t hey Wey . Th is r ap id d eve lop men t o f al ong-estab l ished t ype may h ave b een c aused b y t he A c t o f 1 770 wh ich e stab l ished t he T ha mes C omm iss ioners , who s oon s tar ted b u i ld ing p ound-locks .
B e fore t h is t here were n o l ocks f or 5 0 mi les
u ps trea m t o Ma idenhead , a bove wh ich t here were many f lashlocks , o r r emoveab le we irs .
B arges g oing u pstrea m h ad t o b e h au led o r w inched o ver
t he m , a nd d ownstrea m t hey h ad t o ' shoo t ' t he we ir .
On ly n ear Ox ford was
t here a g roup o f p oundlocks b u i l t i n t he e ar ly 1 7th c en tury . These r iver-barges were v ery l i ke t he e ar ly S evern t rows a nd g enera l ly s im i lar t o e ar ly N or folk k ee ls . THE PUNT A bove L ondon t he sma l l p un t 6 -7 m l ong h as p robab ly a lways b een t he c harac ter is t ic work ing-cra f t o f wa ter men , mi l lers a nd f i sher men .
An u m-
b er a re s hown o n L oggan 's v iew o f Ox ford i n 1 675 , b u t t he t ype i s l i ke ly t o b e much e ar l ier ; a sma l l p un t o f t he 1 1th c en tury A .D . h as b een f ound i n Den mark .
B e fore t he l a te 1 9 th c en tury t hey were workaday v esse ls .
T he
V ic tor ians t ook t he m u p f or r ac ing a nd f or f am i ly b oa t ing a nd h undreds a re s t i l l i n u se t oday .
2 95
L arger p un ts o f 1 0 t o 1 8 m l ong a re a lso s hown o n t he 1 675 v iew .
T hey
a re s t i l l q u i te c o m mon ly u sed f or r iverside ma in tenance-work a nd , i n a l l k inds o f w id ths , f or f err ies.
One o f t he v ery f ew v iews o f ap un t i n L ondon
i s t he H orse ferry a t L a mbe th s hown , a lso i n 1 675 , b y H ol lar i n h is P rospec t o f L ondon a nd Wes tm inster .
T h is h as a c oach a nd p a ir a broad a nd s ee ms t o
b e worked b y ap a ir o f s weeps a t t he f orward e nd . F ro m t h is p er iod p un ts were c arr ied a bou t o n waggons i n mi li tary ' pon toontra ins ' a nd f requen t ly u sed f or i mprov ised r iver-crossings .
Af ine
v iew o f ap rac t ise-crossing i n J u ly a nd August 1 780 a t G ravesend s hows s tr ings o f t he m , w i th d rawbr idges f or d ise mbark ing b e ing h au led a cross t he Tha mes o n c ha ins , r a ther b e la ted p rac t ice f or t he Amer ican war . F a ir ly s oon a f ter t h is l arge-sca le d e mons tra t ion o f t he v a lue o f t he p un t , a nd a r epe t i t ion o f t he e xerc ise i n 1 799 , t he r iver-barges d escr ibed a bove were r ep laced b y v ery l arge c argo-pun ts u p t o 3 0 m i n l eng th .
F ro m a bou t
A .D . 1 800 u n t i l r a i lways k i l led t he r ivertra f f ic i n t he mid 1 9 th c en tury t hese c argo-pun ts were i n g enera l u se o n t he T ha mes , a nd a re s hown i n many i l lustra t ions . Wi th in a g enera t ion o f t he ir i n troduc t ion o n t he u pper r iver s im i lar p un tl ike f or ms were a dop ted b o th f or l i gh ters i n L ondon wa ters a nd f or s a i l ing-barges i n t he T ha mes e stuary .
I t wou ld b e a t trac t ive t o s ugges t
t ha t t hese d eve lop men ts were s t i mu la ted b y t he mi l i tary p on toons o f 1 780 o r b y t he l arge c argo-pun ts o n t he r iver , b u t t he l i nes o f t he ' Cha lk b arge ' p ub l ished i n 1 788 s hows a t endency t owards t he f or m . T he mos t l i ke ly e xp lana t ion i s t ha t t he e ver-grow ing d e mands f or h eavy t ranspor t i n L ondon l ed t o t he s i mp les t d es ign a nd c ons truc t ion f or r iverb arges , l igh ters a nd s a i l ing b arges a l ike . T he l arges t s ize o f Tha mes c argo-pun t h as l a te ly b een ma tched b y t he g roup o f R o man s tone-carry ing p un ts f ound i n H o l land , a nd t he o r ig in a nd e ar ly h istory o f t he p un t i s o f t he g rea tes t i n teres t a nd mer i ts f ur ther r esearch . 4
NOTE I l lus tra t ions o f b oa ts i n t he T ha mes n ear Ox ford may b e f ound i n t he C ard-Index o f l oca l v iews i n B od le ian L ibrary ; Ma lcha ir s ke tch-books o f C . 1 770-80 i n Wes tern Ar t Draw ings c o l lec t ion ,
A sh mo lean Museum ;
Taun t p ho tographs a nd o ther c o l lec t ions i n Ox ford C ity L ibrary . I l lustra t ions o f b oa ts i n t he T ha mes n ear L ondon may b e f ound i n t he GLC Map a nd P r in t C o l lec t ion , C oun ty H a l l , a nd t he Gu i ldha l l L ibrary P r in t C o l lec t ion .
Most b oroughs a long t he r iver h ave u se fu l v iews i n t he ir
r e ference l i brar ies.
2 96
REFERENCES Braun , G . a nd Mogenberg , F .
C iv i ta tes Orbis T errarum ( 1 572 ) 3 , f acsi m i le
b y GLC i s w ide ly a va i lab le . Gr i f f i ths , R .
An E ssay t o p rove t ha t t he J ur isd ic t ion a nd C onservacy o f t he
R iver T ha mes & c Loggan , D .
( 1 746 ) 1 59 .
Oxon ia D ep icta ( 1 675 ) .
Marsden , P .
" A S even teen th-cen tury B oa t f ound i n L ondon" , P os t- Medieva l
Archaeo logy 5 ( 1971 ) 8 8-98 . Og i lby J ., a nd Morgan W . s ca le 1 :
A L arge a nd Accura te Map o f t he C ity o f L ondon
1 200 ( 1 676 ) , f acsi m i le e d i ted b y C . We lch f or L ondon a nd
Midd lesex Archaeo log ica l S oc ie ty ( 1894 ) .
2 97
D ISCUSS ION d e Weerd :
An i l lustra ted p re l im inary r epor t o n t he t hree d ugou ts . t he t hree b arges a nd t he r udder f ro m Zwa m merda m w i l l b e p ub l ished s oon . I tw i l l i nc lude a d iscussion o n R o man p er iod s h ip c onstruc t ion a long t he R h ine . T he r e ference i s : M. D . d e Weerd ( f or thco m ing ) ' Ro merze i t l iche T ranspor tsch i f fe u nd E inbau me a us N igrum Pu l lu m/Zwa m merda m , Prov inz Z u idho l land , N ierder lande ' Ak ta X . L i meskongresses ( 1 974 ) Xan ten/N i j megen .
Arno ld :
I n t he d i fferen t c lassi f ica t ions p roposed , we h ave t oo much t endency t o e xa m ine o n ly t he p lanks a nd o ccasiona l ly t he f ra mes , b u t t hese r epresen t o n ly p ar t o f t he b oa t . We s hou ld a lso c onsider t he c au lk ing , t he mas t s tep a nd o ther f i t t ings f or s a i l ing , a nd o ther d eta i ls . I ft he s ize o f t he b oa ts c an v ary i n p ropor t ion t o t he i n tensi ty o f t rade i n a n a rea , t he d e ta i led t echn iques i n t he s h ipbu i ld ing may b e s im i lar ly i n f luenced .
I t
i s b y t he s tudy o f t hese sma l l d e ta i ls ( bu t a re t hey r ea l ly d e ta i ls?) t ha t we e s tab lished a n o r ig ina l h yp othes is f or t he c ons truc t ion o f t he B eva ix b oa t ( Arno ld , 1 974 ; 1 39 F ig . 5 ) .
We may c o mpare t he
c o mp lex c au lk ing o f t he N or th F err iby b oa ts ( l ash ingmoss-wooden l a th-lash ing f asten ing t he p lanks t oge ther ) w i th t hose o f B eva ix o r Y verdon ( rope- moss-wooden l a th-s ma l l n a i ls ) . E l l mers :
Io r ig ina ted t he t er m ' Ce l t ic b oa t ' a nd Id id s o t o s how t ha t t he C e l ts h ad t he ir own b oa ts wh ich were n ot i n a ny way r e la ted t o Med i terranean o r t o S cand inav ian b oa ts . ( Jahrbuch d es R om isch - G er man ischen Z en tra l museu ms Mainz ( 1966 ) , 1 6 : 7 3-122 ) .
Bu t
p erhaps we s hou ld n a me t h is d i f feren t s ty le o f b oa tb u i ld ing " Con t inen ta l"? Wi lson :
T he word C e l t ic d escr ibes l anguages , t here i s n o o ther p oss ib le way i tc an b e u sed , i ts hou ld n o t b e u sed t o d escr ibe t hese b oa ts .
L e ts t ry t o u se a n a me l i ke
' Rhen ish ' o r ' Western European R hen ish '. McGra i l :
Why n o t c a l l t he m E l l mers t ype 1 o r Arno ld 's t ype 2 a nd s o o n?
Marsden :
Is ugges ted i n my p aper t ha t i to ugh t t o b e ' ce l t ic ' w i th a sma l l ' c ' , b u t ' con t inen ta l ' m igh t b e a ppropr ia te .
d e Weerd :
T he Zwa m merda m b oa ts , a nd p erhaps t hose i n S w i tzer land t oo , a re R o man p rov incia l b arges , a nd t h is may b e t he t er m t o u se .
2 98
U pha m :
These b oa ts o pera ted i n at ide , whereas t he R o mans h ad more o r l ess t ide less s eas , av ery sma l l r ange o f t ides .
T hese s o c a l led c e l t ic b oa ts a re n ear ly a l l
f la t b ot to med a nd t hey h ad t o b each .
I s t he word
' t ide ' r e levan t i n y our t ype n a me? Wr igh t :
We migh t t h ink o f ' Ga l lo-Ro man ' o r ' na t ive G a l l ic ' f or t hese b oa tbu i ld ing t rad i t ions .
Wi lson :
We d o n o t k now t ha t t hese b oa ts h ave t he ir o r ig in i n a Ga l lo-Ro man o r C e l to-Ga l lo-Ro man o r Ang lo-Ro man o r B r i to-Ro man a rea .
We d o k now t ha t t hey a re
g enera l ly f ound i n r ivers , a nd t ha t t hey may h ave s o me th ing t o d o w i th t ides .
It h ink t hough t he b est
r u le i n t hese c ircu mstances i s t o u se a p lace n a me f or at ype , t he Zwa m merda m t ype o r t he B lack fr iars t ype . C rum lin-Pedersen :
There a re n ow s u f f ic ien t b oa t f inds t hroughou t n or th wes t Europe t o p er m i t s pecia l ists t o i nvest iga te i n s o me d e ta i l t he s h ipwr igh tery a nd t he b as ic b oa tbu i ld ing t rad i t ions l y ing b eh ind t he i nd iv idua l f inds .
T h is w i l l
b r ing u s t o a sk whe ther t hese a re d eve lop men ts w i th in ap ar t icu lar a rea .
We s hou ld r ecord d e ta i ls o f t he
b oa tbu i lder 's t rade , t he way h e t ack les c ons truct iona l p rob le ms , a nd t he s upp ly o f t imber a va i lab le t o h im ; a nd t hese f ea tures , t oge ther w i th more a rchaeo log ica l f ac ts , w i l l e nable u s t o p lace t he f ind i n ab oa tbu i ld ing t rad i t ion .
T he o vera l l p ic ture s ee ms t o me t o b e o ne
o f an umber o f d i f feren t l ines o f b oa tbu i ld ing e x isting a t t he s a me t ime .
A t ag iven t ime c er ta in o f t hese
b asic l ines a re d eve loped i n to t he l arger s h ip o f t he p er iod .
Bu t t h is d oesn 't mean t ha t a l l t he o ther l i l ies
d isappear ; t hey r e ma in a s sma l l b oa ts , a nd o ne h undred y ears l a ter a nother o f t hese i s b rough t f orward b ecause e cono m ica l , p o l i t ica l , a nd t echn ica l p ossib i l i t ies e ncourage b u i ld ing i n t ha t c ons truc t ion . E l l mers :
C hr is tensen 's c lassi f ica tion c onsiders s o me impor ta n t c on truc tiona l d e ta i ls a nd t akes t hese a s g u ide l i nes t o s epara te b oa ts i n to s even o r e igh t g roups .
C hr is tensen :
Sma l l d e ta i ls a re a lso e x tre me ly i mpor tan t a nd e spec i a l ly f or p eople who g o o n a ppren t icesh ip a nd l earn b y c opy ing wha t t he master d oes .
Y ou may c hange t he
s hape a nd s ize o f t he s h ips b u t t he b u i lder w i l l s t ick t o h is d e ta i ls o f c onstruc t ion .
T he f inger p r in t o f t he
b oa twr igh t i s i n t he sma l l d e ta i ls o f b oa tbu i ld ing a nd t hese mus t b e s tud ied .
We n ow k now s o me o f t he
r epe toire u sed b y a nc ien t b oa tbu i lders i n E urope .
We
d on 't k now a l l , b u t Iam p er fec t ly s ure t ha t n ew f inds may b e v ery b road ly l u mped i n to t he o ld c a tegor ies . I f we l ook c are fu l ly a t e ach n ew f ind we w i l l b e a b le t o r e f ine o ur g roups a nd make more g roups. 2 99
Marsden :
There a re t wo ma in a spec ts i n a ny s h ip o r b oa t , o ne i s t he f or m a nd t he o ther i s t he d e ta i led c onstruc t ion . And a l though f or m may c hange a ccord ing t o t he e nv ironmen t ab oa t works i n a nd t he u ses t o wh ich i ti s p u t , t he d e ta i ls , t he n a i l f asten ings , a nd t he c au lk ing me thods , t end t o l i ve o n i n to t he more r ecen t t ypes .
T he c au lk-
i ng i s g enera l ly moss o n t he R h ine b arges ; a t G uy 's H osp i ta l a nd B lack fr iars t he c au lk ing i s h aze l t w igs . T he s ize o f t he G uy 's H ospi ta l c ra f t s ugges ts i t was a r iver c ra f t , a nd t here fore i t must h ave b een b u i l t o n t he T ha mes o r t he e stuary r ound h ere , i tc an 't b e f ro m t he c on tinen t .
B lack fr iars i s as ea g oing v esse l , w i th
t eredo b or ings i n t he p lank ing .
Bu t i t may b e t ha t
a l though we h ave t wo c ra f t o f v ery d i f feren t s hape t he f ine d e ta i ls o f h aze l t w ig c au lk ing s uggest t ha t B lackf r iars may h ave a lso b een b u i l t o n t he T ha mes o r i n s ou th e as t E ng land . T he a bsence o f h aze l t w igs o n t he R hine l and c ra f t c ou ld mean t ha t t hese were n ot b u i l t i n s ou th e as t E ng land . R obb ;
Y ou h ave a p rob le m r a ther s im i lar t o t ha t w hen a lche my moved t o c he m is try a nd Is uggest t ha t y ou tke t he c harac ter ist ic f ea tures y ou h ave u sed t o d escr ibe t he s h ips , whe ther i ti s t he c au lk ing , o r t he way t ha t t he p lanks were j oined t oge ther o r wha tever , a nd d escr ibe t hese b oa ts u sing a v ocabu lary w i th s o me k ind o f s hor thand s uch a s t he i n i t ia l l e t ter a s was u sed i n c he m is try , Cf or c arbon 0 f or o xygen a nd s o o n , s o t ha t y ou g e t ac oded d escr ipt ion .
Once y ou p u t t h ings
i n to c lasses s uch a s C e l t ic b oa ts y ou b eg in t o s ugges t t hen t ha t t here i s an eccessary c onnec t ion b e tween t he m , b u t t here i s n o t n eccessar i ly a t echn ica l c onnec t ion b e tween t he m , s i mp ly t he t h ird c onnec t ion . C oa tes :
S ea g oing b oa ts move a bou t a nd t hey a l l n eed mend ing s o i ti s q u i te l i ke ly t ha t ab oa t wh ich was b u i l t a t An eeds t o b e mended a t Bq u i te a l ong way away , b y a man who s erved h is a ppren t icesh ip i n Bb u t p erhaps h ad a lso b een t o C .
S h ips a lso h ave t o b e r e-cau lked .
T here
mus t b e ag rea t m ix ing o f c lassi f ica t ions w i th in o ne b oa t , s o a Dan ish b u i l t s h ip migh t we l l e nd u p i t s l i fe w i th R h ine land c au lk ing a nd s o mebody e lse 's wa ter l ine p lank ing , s o when t he b oa t f ina l ly c o mes t o r es t a nd i s d ug u p b y t he a rchaeo log ist wha t i s i t s c lassi f ica t ion? McGra i l :
Ir eco m mend q uan t i ta t ive me thods t o P e ter Marsden a nd Arne Em i l C hr is tensen .
I ft hey r ecord e very th ing o n
af ind , a nd p rov id ing t hey h ave a s u f f ic ien t ly l arge a nd r e l iab le d a ta b ase , t hey w i l l t hen b e a b le t o s earch f or t he o p t i mu m c lass if ica t ion s che me , e ither b y h and o r b y t he d readed c o mpu ter .
3 00
C hr is tensen men t ioned t he l ogboa t f ro m V a laar Moor wh ich C rum l in-Pedersen h as s a id was e xpanded . ( i n H assld f , 0 . ( ed .) 1 972 , S h ips , a nd S h ipyards , S a i lors , a nd F isher men : 2 08-234 ) . Iam n o t a bso lu te ly c onv inced b y h is d e monstra t ion .
Are t here a ny
e thnograph ic p ara l le ls f or o ak l ogboa ts b e ing e xpanded? C hr is tensen :
Th is h as A ot b e t nr esearched a t a l l .
We k now t ha t
e as tern Europe u ses a spen , p op lar a nd o ccas iona l ly s pruce f or e xpanded d ugou ts , a nd t he western c oast o f t he Un i ted S ta tes u ses r ed wood .
The Va laar
Moor b oa t s ee ms t o b e a n e xpanded d ugou t , t he b o t to m p lank o f t he H jor tspr ing b oa t may a lso b e a n e xpanded d ugou t . C rum l in-Pedersen :
T hese s hou ld b e i nvest iga ted f ur ther .
Ir eco m mend c lose s tudy o f t he r e la t ions b e tween t he G raveney b oa t a nd t he med ieva l s h ipwrecks f ound a t B lack fr iars a nd C us to ms H ouse .
I tw i l l b e wor thwh i le
g oing i n to s h ipwr igh tery h ere t o s ee whe ther y ou h ave f ea tures i nd ica t ing a l oca l T ha mes t rad i t ion d ur ing t h is p er iod .
An u mber o f s peci f ic f ea tures we s ee i n
t he G raveney B oa t ; s o me s ec t ions i n t he f ra mes , t he way t ha t t he h ood o nds c o me u p t o t he s te m a nd s tern , a nd t he k ee l s ec t ion , a re a lso f ound i n t he med ieva l v esse l f ound a t B lack fr iars ( Marsden , P ., 1 972 , ' B lack fr iars Wreck 3 ' .
I n terna t iona l J ourna l o f
Nau t ica l Archaeology , 1 : 1 30-132 .) It h ink t he i n terac t ion b e tween n av iga t ion , s e t t lemen t a nd f or t i f ica t ion i s v ery impor tan t , a nd t hese f ac tors o f fer a c lue t o u nderstand ing many o f t he more g enera l p rob le ms i n a rchaeo logy . H oward :
T here a re t wo v ery p ro m ising s i tes t ha t a re i n p ossib le d anger a nd It h ink s hou ld b e wa tched .
One i s t he o ld
p or t a t H edon a bou t s ix mi les f ro m Hu l l , where o ne o f t he h avens h as a lready b een b u i l t o ver .
T ha t was
s i l ted u p s o mewhere a bou t 1 600 a nd t here mus t b e q u i te a l o t o f i n teres t ing s tu f f i n t he b ot to m t here . T he o ther o ne i s t he o ld h arbour o f C as t le R is ing i n N or fo lk .
T he v i l lage w i th i t s marke t s quare i s n ow
l arge ly g rass ; i ti s o n t he s lope o f ah i l l o ver look ing af la t p lace wh ich i n t he 1 500s was s t i l l washed b y t he s ea , a ccord ing t o as ta te men t i n t he c hurch t ha t t he waves b roke t he c hurch w indows .
It hink we s hou ld
wa tch t hese s i tes b e fore t he bu i lders g e t a t t he m .
3 01
2 3 .
S U M MARY AND CONCLUD ING RE MARKS B asi l G reenh i l l
Is ee t ha t Iam d own o n t he p rogra m me t o g ive a b r ie f s um mary o f t he p roceed ings o f t h is S y mposiu m t o b e f o l lowed b y f ur ther d iscussion .
N ow
t h is a ssign men t , i ts ee ms t o me , i s a l mos t i mposs ib le a nd Ia t te mp t i to n ly u nder t he p rotec t ion o f my c are fu l ly g uarded ama teur s ta tus. Y ou may wonder why t he s u m mary s hou ld c o me n ow when t here a re f ur ther s essions t o morrow . It h ink t ha t t hose r esponsib le f or d ra f t ing t h is p rogra m me were q u i te r igh t t o p u t t he s u m mary i n h ere b ecause i ti s c lear when y ou l ook a t t he p rogra m me t ha t i t was d esigned t o b r ing o u t c er ta in t he mes a nd Is ha l l e numera te t he m i n a mo men t a s Is ee t he m .
I n t he f irst t hree d ays o f d iscussion t hese t he mes
were b rough t o u t a nd o n t he f our th d ay , h av ing b u i l t t he v esse l a s i t were , a s av ery s pec ia l r eward w e g e t t he c arved a nd g i lded work , t he p resen ta t ion i n o ne f or m o r a no ther f or t he f irs t t ime i n t h is c oun try o f o ne o f t he most impor tan t a nc ien t b oa t f inds e ver , t he Cheops b oa t . N ow It h ink p ersona l ly t ha t o n t he who le t he p rogra m me h as worked o u t p re t ty s a t isfac tor i ly , a nd t ha t s evera l i mpor tan t p oin ts h ave emerged i n t he d iscussions.
One t hing t ha t i s c lear i s t he i mpl ic i t c on f ir ma t ion o f ad e fin i-
t ion o f b oa t a rchaeo logy wh ich we h ave t ended t o a dop t a t t h is Museum - a nd l e t 's n ot g e t i nvolved a t t h is s tage i n a rgu men ts a bou t t he d e f in i t ion o f b oa t o r s h ip i n t h is c on tex t , b u t u se t he t er m b oa t a rchaeo logy w i thou t c o mm i t men t . N ow i n s e t t ing u p t he Archaeo log ica l R esearch C en tre ( ARC ) we h ad t o d e f ine o ur o b jec t ives , and we d id t h is i n b road t er ms , a s t he s tudy o f b oa ts b e fore " t he t echn ica l r evo lu t ion o f t he 1 5 th c en tury .
T h is a pparen t ly w idespread
r evo lu t ion a ppears t o h ave t aken p lace a t af an tast ic s peed a nd t o h ave h ad a p ro found e f fec t u pon t he h istory o f man .
We h ave f or o ur p urposes d ec ided
t o t rea t t he s tudy o f t h is r evo lu t ion a s as epara te s ub jec t , a nd t o t rea t t he s ubsequen t d eve lop men t o f t he s h ip a s a n h istor ica l ma t ter , a va i lab le i n for mat ion o f wh ich i s i ncreas ing ly r e in forced b y e v idence o f a n a rchaeo log ica l n a ture l arge ly a s ar esu l t o f t he w ork o f d ivers.
T h is t opic t hen merges i n to mar i t i me
i ndus tr ia l a rchaeo logy w i th o ur work o n t he k e tch , S ha mrock a t C otehe le i n t he west c oun try , wh ich h as c lose p ara l le ls w i th t he work b eing d one a t t he D an ish Na t iona l Museum o n t he ir g a l leas n ow r ebu i l t a nd a t s ea t h is s um mer .
T he
d iscussions i n t h is s y mpos ium h ave , It h ink , i mp l ic i t ly t ended t o c on f ir m t h is b road b rush k ind o f d e f in i t ion o f t he f i e ld o f i n terest we c over . T he p a t tern o f d iscuss ion wh ich h as d eve loped h as b een o ne o f i ncreasing s er iousness a nd d ep th a nd Iwou ld l i ke t o t hank t he s peakers who h ave t aken s uch i m mense t roub le t o p resen t t he ir f ie lds o f i n terest t o u s s o c lear ly a nd s pec i f ica l ly , s peak ing i n my l anguage wha tever t he ir l anguage o f o r ig in . S peak ing a ga in p ure ly p ersona l ly If ound t he a ddresses o f Dr . L evy a nd Dr . d e J ong g ave a n ew d i mension t o as ub jec t w i th wh ich Ih ad b een p rev ious ly u n fa m i l iar , a nd t ha t P ro fessor F i lgue iras 's f asc ina t ing p resen ta t ion o pened
3 03
a who le n ew f ie ld o f d e ta i led s tudy o f ag roup o f European b oa t t ypes.
Ih ave
n o d oub t a t a l l t ha t e ach o f y ou h as r ece ived s im i lar f resh s t i mu lus t hrough o ne o r more o f t hese f or ma l p resen ta t ions a nd f ro m t he i n terven t ions i n t he o f ten i n tens ive d iscussion wh ich h as t aken p lace . N ow It hink a t t h is s tage Imigh t t ake t he o ccasion o f my r e ference t o P rofessor F i lgue iras t o d raw o u t wha t s ee ms t o me t o b e t he f irs t o f t he ma in s trands wh ich Ih ave d e tec ted a s c om ing o u t o f t he c o mp lex i n te l lec tua l s p inn ing p rocess t ha t we h ave a l l b een g o ing t hrough i n t he l as t t hree d ays .
T h is
h as b een r e in forced p ar t icu lar ly b y i n terven t ions f ro m Arne Em i l C hr is tensen a nd E r ic McKee .
I ti s t ha t we s hou ld d o a l l we c an t o e ncourage a nd f ur ther ,
wh i le t here i s s t i l l t ime , t he c o l lec t ion o f t he mos t d e ta i led r ecords t ha t c ircums tances p er m i t -a nd t h is c an b e a ny th ing f ro m a f ew p hotographs t o at hes is s tudy - o f s urv iv ing t rad i t iona l b oa t t ypes .
Is hou ld s ay " so c a l led"
t rad i t iona l b oa t t ypes b ecause o ne a spec t o f t h is s tudy mus t b e t he d egree t o wh ich t hey a re t rad i t iona l .
It h ink i th as emerged c lear ly a lso t ha t we must
t rea t t h is ma ter ia l n o t a s e v idence o f wha t was d one i n t he p as t b u t a s e v id ence o f wha t was p ossib le o r migh t h ave b een p ossible w i th in t he f ra mework o f l im i ted t echno log ies a t d i f feren t p er iods i n d i f feren t p laces , a nd t o p rov ide u s a lso w i th p ossib le s o lu t ions wh ich c ou ld f ro m t ime t o t ime h ave b een a dop ted i n t he p ast .
A t G reenwich we h ave t aken t h is p ar t icu lar message v ery
much t o h ear t a nd a t a mee t ing a s r ecen t ly a s t h is l unch t ime , we h ave b egun t o l ay d own t he f ra mework o f ap o l icy f or t he a cqu is i t ion o f e thnograph ic b oa t ma ter ia l i n t h is Museum , t here h av ing b een a r ecen t i ncrease i n a cco moda t ion wh ich makes t h is more p ossib le t han i th as b een i n t he p ast . T he s econd t he me It h ink i s t ha t t here s ee ms t o b e ag enera l f ee l ing t ha t t here i s ar ea l n ecessi ty f or s o me f or m o f g lossary i n t he E ng l ish l anguage wh ich migh t b e t he b eg inn ings o f ag enera l ly a greed t er mino logy t o u se i n t h is n ew a nd d eve lop ing s tudy o f t he a rchaeo logy o f b oa ts .
N ow Is ense t he
f ee l ing , a nd n o d oub t t he d iscussion a f ter t h is s um mary w i l l c orrec t me i fI am wrong , t ha t t he t ime i s r ipe f or s o me s or t o f i n i t ia t ive .
I ft h is i s s o i t
i s p ossib le t ha t y ou may c are t o c ons ider r eques t ing t he T rustees o f t he Na t iona l Mar i t i me Museum t o c onsider ways i n wh ich t h is Museu m c an move t owards t he p repara t ion a nd p ub lica t ion o f af i rst i l lus tra ted g lossary o f t er ms f or u se b y b oa t a rchaeo log ists . Ih ave c hosen my words c are fu l ly s o t ha t t he c o mm i t men t i fi ti s a sked f or , a nd i fu nder taken , c an b e a s b road a s p ossib le . Ih ave r eason t o b e l ieve t ha t s hou ld t h is S y mposiu m f ee l s uch a c ourse o f a a c t ion d esirable , t he Trus tees may we l l f ee l t ha t t h is i s a n a ppropr ia te f ur ther a dd i t ion t o t he work we a re a lready u nder tak ing i n t he a rchaeo log ica l f ie ld . The t h ird s trand emerges l ess c lear ly , b u t i ti s n ever the less t here a nd i t c o mes o u t p ar t icu lar ly i n t he p resen ta t ions y es terday b y Mr . G raha m a nd b y S ean McGrai l , t he N oah o f o ur ARC , i f Ic an r e turn t he h appy c o mp l i men t h e p a id me y es terday .
T h is s trand c en tres r ound t he c on troversia l ma t ter o f
q uan t i ta t ive me thods a nd t he e stab l ish men t o f i n terna t iona l ly a greed a t tr ibu tes f or r ecord ing b oa t f inds a nd t he ir a na lys is , p oss ib ly w ith e lectron ic a ids. N ow h ere we a re g e t t ing i n to p re t ty d eep wa ter . Is a id a t t he b eg inn ing o f t h is S y mposium , a nd a lso a t t he b eg inn ing o f t h is a ddress , t ha t Ih ave b een v ery c are fu l t o ma in ta in my ama teur s ta tus .
P erhpas n ow Ic an t ake t he l i ber ty a s
an on-pro fessiona l t o s ay t ha t , l ook ing i n f ro m t he o u tside , a rchaeo logy s ee ms , p erhaps e ven more t han a ny o ther f or ms o f h uman a c t iv i ty , t o d epend f or t he 3 04
c ons iderable r esources o f n ervous e nergy r equ ired o f t hose who p ar t ic ipa te i n i ts uccess fu l ly , u pon i n tense p ersona l i nvo lve men t a nd t h is i nvo lve men t means t ha t e ven more t han most p eop le , a rchaeo log ist , p ro fessiona l a nd f r inge ama teurs , d o n o t w ish t he a nn ih i la t ion o f b e ing merged i n to P eer G yn t 's b u t ton mou lder 's c rucib le o f b o i l ing b rass .
And t ha t p erhaps i s h ow
s o me p eople , -a nd Id e l ibera te ly c hose t he S cand inav ian s im i le , -v ery u nders tandab ly s ee a c o mpu ter .
N ever the less f or t he l ong t er m d eve lop men t o f t he
s tudy i ts ee ms t o me t ha t t here mus t emerge a q uan t i ta t ive b ranch w i th a greed i n terna t iona l s tandards a nd a greed s e lec ted d a ta . v ery s low g row th .
Bu t It h ink t h is w i l l b e a
F ro m S ean McGra i l 's work t here may emerge t he p ossib le
b asis o f aB r i t ish l i s t o f a t tr ibu tes f or r ecord ing l ogboa ts .
I ti s l i ke ly t ha t
t here w i l l b e mer i t p erhaps i n t he e x tension o f t h is i n t wo d irec t ions s low ly . One , f or i tt o b e t he b as is o f a n i n terna t iona l s ys te m o f l ogboat r ecord ing ; a nd s econd f or a g radua l e x tens ion o f t he s ys te m i n to p lank b u i l t b oa ts. g row o f i t s own a ccord s pon taneously .
Th is mus t
T hese s ys te ms may we l l b e c apab le
o f f u ture c o mpu ter isa t ion a s an a tura l d eve lop men t , h appen ing r easonab ly p ain lessly b u t i n p ara l le l w i th t he c on t inua t ion o f t he c o mp lex o f more t radi t iona l me thods wh ich h ave b een s u m mar ised a s " in tu i t ive" i n t hese d iscussions .
A s
t he i n terna t iona l s tore o f d a ta g rows s o i t may we l l t ransfor m i t se lf i n to s o met h ing wh ich J ona than C u tb i l l may b e p repared t o a ccep t a s amenab le f or d ev e lop men t a s ab ank , b u t t he g row th mus t b e s low a nd g en t le a nd n a tura l , a nd i tc anno t o ver load p eople whose e x ist ing c omm i t men ts a re f unda men ta l t o t he d eve lop men t o f t he s tudy .
N ow h ere Imust make a f ur ther q ua l ify ing p oin t ;
h owever much we s trugg le , t he b u t ton mou lder 's c ruc ible wa i ts f or u s a l l a nd i nev i tab ly t he s tudy i s g o ing t o b eco me more s c ien t i f ic .
T he p rocess r ea l ly
b egan w i th t he i n troduc tion o f n ava l a rch i tec ts i n to t he f ie ld , a nd O le C ru m l inP edersen h i mse l f was a g rea t p ioneer . e ng ineer 's p oin t o f v iew .
Then c a me E r ic McKee w i th t he
And y ou w i l l h ave r ea l ised f ro m t he p apers p resen ted
b y h im a nd J ohn C oa tes u nder t he c ha ir mansh ip o f Ewan C or le t t , h ow much s uch s pec ia l ists c an c on tr ibu te t o o ur u nders tand ing o f a ncien t b oa ts a nd t he ir c apab i l i t ies .
T he p resence i n t h is r oo m o f s uch a f or m idab le c o mb ina t ion a s
C or le t t , C oa tes a nd McKee i nd ica tes o ur i n ten t ions a t Greenw ich .
Bu t l e t u s
make o ne p oin t c lear , a s f ar a s we a re c oncerned , t he a rchaeo log is t must r e ma in i n c harge , n ava l a rch i tec ts , e ng ineers , a nd s im i lar s pec ia l is ts a re a dv isers , a nd t he a rchaeo log ica l s taf f w i l l move more a nd more i n to t he g ene ra l p rofessiona l f ie ld i n t he b roader s ense .
The k ey word i s a rchaeo logy ,
a nd p ro fessiona l is m i n a rchaeo logy i s p ara moun t . N ow t he l as t o f t hese ma in s trands a s Is ee t he m , emerged p ar t icu lar ly c lear ly i n t he d iscussion a f ter t he t wo p apers o n r ecord ing f inds a nd p resen ti ng i n forma t ion .
D oes t he s y mposium f ee l t ha t t here i s ac ase f or t he
p ub l ica t ion o f as i mple g u ide , a n e le men tary f i rs t-a id h andbook b eg inn ing w i th s o me s uch p hrase a s " i f h uman ly p ossib le d o n o t d is turb t he c asua l ty" , f or t hose who b eco me i nvo lved w i th a n a ncien t b oa t f ind?
Iam t o ld t ha t t he
Br i t ish Museu m o f N a tura l H is tory h as a p ub l ica t ion e n t i t led Wha t t o d o w i th as tranded Wha le .
N ow i ft h is i s s o we migh t l ook a t t h is w i th a dvan tage ,
p erhaps t he p ara l le l migh t b e c loser t han we t h ink .
Bu t t o b e s er ious d o we
f ee l t ha t t here i s a n o ccasion f or s uch a p ub l ica t ion a nd t ha t i t wou ld s erve a u se fu l p urpose ? Wha t Ih ave i n m ind wou ld b e s tr ic t ly f or t hose who d o n o t k now t he s harp e nd f ro m t he b lun t , b oa t a rchaeo logy s peak ing .
3 05
It h ink i th as a lso v ery c lear ly emerged f ro m t he d iscussion t ha t we c an a l l o f u s o n ly a pprox i ma te , o n ly d o t he b es t p ossib le i n t he c ircu ms tances w i th e ach i nd iv idua l f ind .
I ti s t he f unc t ion o f ap rofessiona l i ns t i tu t ion s uch a s
t hose wh ich h ave emerged o r a re emerg ing i n S candinav ia , G er many a nd e lsewhere , a nd i n t h is c oun try , t o s et s tandards , t o d eve lop d isc ip l ines a nd t o d eve lop me thods.
L im i ted a nd i nadequa te a s we c onsider o ur r esources s t i l l
t o b e , a nd Iam s ure o ur c o l leagues h ave t he s a me f ee l ing a bou t t he irs , most p eop le f aced w i th b oa t a rchaeo log ica l f inds w i l l d o s o w i th e ven more l im i ted r esources .
C o mpro m ise w i l l c on t inue t o b e t he o rder o f t he d ay , b u t i ts hou ld
b e ac o mpro m ise o f d eve loping i n terna t iona l p ro fessiona l is m a nd s tead i ly d ev e loping s tandards t o wh ich p eop le w i l l s tr ive t o a pprox i ma te . N ow a s uggest ion - i ti sn 't a t he me , i ti s as uggest ion - wh ich h as b een made more t han o nce i n o ur d e l ibera t ions i s t ha t t he S cand inav ian w ork ing g roup o r s o me th ing l i ke i tm igh t b e r ev ived o r ap ara l le l s tar ted e lsewhere , a nd Iwou ld l i ke t o a dd my t r ibu te t o t hose who h ave p ra ised t he w ork o f t h is g roup a nd p o in ted o u t t ha t t he ir p ub lica tion i n E ng l ish " Sh ips a nd S h ipyards , S a i lors a nd F isher men" i s r equ ired r ead ing f or a nybody who g e ts i nvolved i n t h is s ub jec t . We i n t h is Museum h ave s o me th ing s im i lar g o ing a lready , wh ich was a c tua l ly i nsp ired b y t he S cand inav ian e xa mp le . Wh i le a rchaeo log ica l work i s g oing f orward i n t he ARC , E r ic McKee d oes h is e thnograph ic r ecordi ng , i f we c an u se t he t er m ; C a mpbe l l Mac Murray i s b eaver ing away o n t he s ocio log ica l t he mes f ro m o ra l s ources ; I an Merry a nd o thers work w i th u s o n r eg iona l mar i t i me h is tory ; a nd o ther p eople a re work ing f or u s o n s h ip r eg istra t ion ma ter ia l . I n c onc lusion , It h ink t ha t t h is S y mposium h as b een v ery i mpor tan t f or a n umber o f r easons , o f t he s tudy .
a nd t he c on t ibu tors h ave i l lumina ted t he v ar ious b ranches
T he s y mposiu m h as c lear ly r evea led t he c ross c onnec t ions a nd
t he ways i n wh ich t he v ar ious i n ter locked d isc ip lines a re d eve loping t owards an ew b ranch o f a rchaeo logy . a ge i n t h is c oun try .
P erhaps t h is S y mpos iu m marks o ur c om ing o f
I ti s , a f ter a l l , 4 0 y ears s ince t he g rea t l andmark o f
Ted Wr igh t 's s tro l l a long t he t e mporar i ly r evea led h ard o n t he n or th s hore o f t he Hu mber , a nd a bou t t he s a me t ime s ince t he f irs t o pen ing o f t he g rave a t S u t ton H oo , a nd t we lve y ears o r more s ince t he g rea t p ioneer s trugg les o f P e ter Marsden i n t he mud a t B lackfr iars w i th t he c on trac tors b rea th ing d own h is n eck .
It h ink t he s tudy o f t he a rchaeo logy o f t he b oa t h as n ow a rr ived
i n terna t iona l ly a nd t he l eve l o f d iscussion h ere h as b een s uch t ha t t he p ub l ished p roceed ings o f t h is s y mposium i s l i ke ly t o s tand a s au se fu l b asic t ex t b ook f or q u i te s o me t ime . Ih ope Ih ave f a ir ly s u m mar ised s o me o f t he ma in t he mes o f o ur d e l iberat ions d ur ing t he p as t t hree i n tensive d ays . T here a re n o d oub t o ther t he mes a nd s trands , s o me o f t he m v ery i mpor tan t t o wh ich p eop le w i l l w ish t o d raw a t ten t ion i n t he d iscussion i n t he n ex t f ew minu tes a nd t hese w i l l b e d u ly r ec orded b y t he i nv is ib le b ugs w i th wh ich t h is L ec ture Thea tre i s i n fested .
T he
d iscussion w i l l b e c onduc ted b y t he C hair man o f t h is s ess ion a nd s ince I c la im n o mer i t f or t h is s u m mary , e xcep t t ha t i t may h e lp t o f ocus t h is f ina l s ession , In ow d raw my c are fu l ly p reserved c loak o f ama teur s ta tus a round me a nd r e turn t o t he a nony m i ty o f t he ma in b ody o f t he h a l l c han t ing a s Id o s o , p ub l ish , p ub l ish , p ub l ish , f or G od 's s ake p ub l ish , b ecause t ha t 's wha t i ti s a l l a bou t . 3 06
D ISCUSS ION Wi lson :
Ib e l ieve t ha t t he f irst t heme men t ioned b y Mr . G reenh i l l t ha t i s t o e ncourage t he r ecord ing a nd c o ll ec t ion o f t rad i t iona l b oa ts a nd s o o n , i s o bv ious ly a n a t iona l c oncern f or a nybody who i s r epresen ted h ere . It h ink we c an a l l a gree w i th t ha t a nd p ress o n w i th t he n ecessary a c t ion .
N ow c an Ih ave c o m men ts o n t he
p roposa l f or a g lossary i n E ng l ish ? Wr igh t :
T here i s ac lear n eed f or t h is g lossary w i th i l lustra t ions . Ib e l ieve t ha t ad eve lop men t o f E r ic McKee 's p ioneer w ork t he G lossary i n h is C lenched l ap o r C l inker w i th s o me i l lus tra t ions wou ld b e a n e x tre me ly h andy t oo l f or a nybody work ing o n t h is s ub jec t i n t he E ng l ish l anguage .
E l l mers :
We a re e xcava t ing s o many t h ings f or wh ich t here i s n o r ea l e xpression i n t he a va i lab le d ic t ionar ies t ha t we n eed a g lossary .
It h ink t ha t i t wou ld b e ag ood t h ing
t o h ave a c en tra l a ddress where we c ou ld s end r epor ts o n f ea tures wh ich o ccur a nd wh ich a re n o t i n c o m mon d ic t ionar ies. Baker :
H av ing worked w i th s o me mar i t i me h is tor ians a nd b een g rea t ly d is turbed b y t he ir misuse o f t he E ng l ish l angua ge , Ip ropose t o t he f u ture e d i tor t ha t s uch a g lossary b e made f or t he ir u se a nd t ha t i tb e k ep t s i mp le .
C or le t t :
T he g lossary s hou ld u se s tandard t er ms , whenever p ossib le , Ih ave h eard t he word ' r ibs ' u sed f requen t ly , b u t n o n ava l a rch i tec t o r s h ip-bu i lder n or ma l ly u ses t he word ' r ibs ' ; h e c a l ls t he m f ra mes.
We d on 't wan t
t wo words , a nd i fy ou a re g oing t o make a s c ien t if ic n ava l a rch i tec tura l a na lysis i ti s much b e t ter t o h ave p roper n ava l a rch i tec tura l t er ms .
Where t here a re
i t e ms f or wh ich t here i s n o modern e qu iva len t t hen o bv ious ly a n ew t er m h as t o b e d ev ised. C hr is tensen :
I n S cand inav ia , i fy ou g o t o ac arve l b u i lder 's y ard a nd a sk h im h e w i l l u se t he word " span t" f or r ib , b u t i fy ou g o t o h is n e ighbour t he c linker b u i lder a nd a sk h im h e w i l l u se t he word ' band" f or t he s a me f i t t ing , a nd t hey a re b o th v ery p os i t ive t ha t t he word i s r igh t f or t he ir p ar t icu lar b oa ts .
Our p rob le m i s t ha t we r un i n to s o
many t h ings where n o p roper n ava l a rch i tec tu ra l t er m e x ists.
Most o f o ur work i s w i th n on-carve l s h ips ,
a nd t he n ava l a rch i tec tura l t er m ino logy i s f or t he s tandard c arve ' s h ip . Wi lson :
It h ink t ha t i ft h is i s t o b e d one i ti s t o b e d one f or wooden b oa ts , s ay b e fore 1 500 , a nd a t er m ino logy d ev e loped o n t he b asis o f wha t h as b een f ound . wha t i s mos t n eeded b y a rchaeo log ists . 3 07
Th is i s
The t h ird q ues t ion i s t he p rob le m o f q uan t i ta t ive me thods , a greed i n terna t iona l s tandards , a nd a greed me thods o f c o mpu t ing .
I n for ma t ion r e tr ieva l i s t he
b ig p rob le m f ac ing a l l a rchaeo log ica l a nd museum work a nd i ti s at h ing wh ich h as o bv ious ly g ot t o b e t hough t o u t i n g rea t d e ta i l .
C an we u se fu l ly h ere a s
ab ody g o a ny f ur ther t han we h ave , o ther t han p erh aps t o g ive i to ur g enera l b less ing ? d e Weerd :
I n for ma t ion r e tr ieva l i s n ot s o u se fu l w i thou t as tanda rd g lossary .
Wi lson :
Wha t d o y ou f ee l a bou t t he f our th i dea o f ag u ide f or t hose f ind ing b oa ts ?
C o les :
S uch a g u ide s hou ld n o t b e d ev ised f or t hose p eop le h ere , i ts hou ld b e f or t he o ther 9 ,500 a rchaeo log is ts i n t h is c oun try who wh i ls t d igg ing may f ind a b oa t , a nd may t h ink i ti s a wooden b ox o r a ny o ld t h ing .
T h is
g u ide wou ld h ave t o b e i n l ay man 's l anguage a nd w ou ld h ave t o b e w ide ly p ub l ic ised , n o t i n t he n au t ica l j ourna ls b u t i n t he j ourna ls t ha t a l l a rchaeo log ists r ead . S uch a t h ing wou ld b e o f v ery g rea t v a lue t o a l l a rchaeol og ica l u n i ts i n t h is c oun try . Wi lson :
C ou ld Is ugges t i n t ha t c ase t ha t p ossib ly t he b es t c o mp i lers o f t h is a re t he N a t iona l Mar i t i me Museu m a nd t ha t t hey s hou ld t hen g e t t oge ther w i th t he C ounc i l o f B r i t ish Archaeo logy t o d is tr ibu te i t .
McGra i l :
We h ave t o ld r eg iona l u n i ts a bou t t he r esearch f ac i l it ies a va i lab le a t Greenw ich a nd o f o ur own r esearch i n teres t , a nd we h ave o f fered t he m s o me g enera l a dv ice emphasising t ha t ab oa t f ind i s ap rob le m , t here a re d i f f icu l t ies i n r ecording a nd c onserv ing i t , a nd p erhaps t hey s hou ld s eek a dv ice .
There may we l l b e ac ase
t hough f or more d e ta i led a dv ice b e ing p ubl ished . Wi lson :
I n t he f ie ld t he g enera l a rchaeo log is t may n o t h ave t ime t o c a l l i n t he s pecia l is t a nd It h ink i ti s f or t h is p ar t ic u lar s i tua t ion t ha t t h is b ook le t i s n eeded .
On t he
o ther h and c on trac tors a nd f ar mers a nd s o o n a re n ot t he p eop le we wan t t o g ive t h is h andbook .
I ti s t he j ob
o f t he C ounc i l f or B r i t ish Archaeo logy a nd i t s v ar ious l oca l g roups t o t e l ls uch p eop le t o r epor t a ny th ing t hey f ind t o t he l oca l museu m. v an d e Merwe :
T he Wreck A c t p ro tec ts s chedu led wreck s i tes u nder wa ter , b u t b oa ts f ound a bove H igh Wa ter c anno t b e p rotec ted u nder t h is a c t ; n or c an t hey b e p ro tec ted u nder t he Anc ien t Monumen ts l eg is la t ion b ecause t hey a re n o t c onsidered monu men ts , t hey a re c onsidered t o b e c ha t te ls , movab le p ossessions .
3 08
C roo me :
We wan t t he Anc ien t Monumen ts l eg is la tion t o i nc lude b oa ts a nd , a s i t were , wrecks o n l and .
E vans :
A f ter t he d iscovery o f t he G raveney B oa t we were g iven a t ime l im i t b y t he K en t Wa ter Au thor i ty b e fore t hey f l ooded t he d yke . Dr . R uper t B ruce Mi t ford t ook s o me r a ther weak a rchaeo log ica l e v idence t o t he Anc ien t Monu men ts B oard i n a n a t te mpt t o s chedu le t he l and u ndernea th t he b oa t a s ah arbour , t o b e u sed i n a l as t d i tch s tand t o p ro tec t t he b oa t , i fn ecessary .
Mars trander :
Dur ing t he d iscussions h ere s evera l me mbers h ave r igh t ly emphasised t he n ecessi ty f or i n terna t iona l c o-opera t ion i n impor tan t f ie lds o f r esearch .
We s ee m
t o b e g enera l ly a greed t ha t t he r ecord ing a nd t horough i nvest iga t ion o f d ugou ts i n t he n or th a nd wes t European a rea o ugh t t o f o l low c o m mon l ines t o r each s a t is fac tory r esu l ts .
I n t h is c onnec t ion i t was a lso p roposed t o
e s tab l ish a n i n terna t iona l d a ta b ank .
There were a lso
o ther impor tan t p roposa ls i nc lud ing a g lossary .
There
s ee ms t o b e ac ase f or e s tab l ish ing a n i n terna t iona l mar i t i me c omm i t tee wh ich c ou ld c o-ord ina te a nd o rgan ise t h is s ort o f r esearch ,
a nd wh ich c ou ld ma in ta in c on-
t inu i ty b e tween mee t ings , a nd h ave t he r espons ibi l i ty f or p lann ing a nd a rrang ing f u ture s y mposia . E d i tor ia l N o te .
A f ter a t horough d iscussion o f P ro fessor Mars tander 's
p roposa l i t was a greed t o f or m a n a d h oc work ing p ar ty o f 1 2 me mbers t o p lan t he f or ma t ion o f ab ody t o b e k nown a s t he I n terna t iona l S y mpos ia o n Boat a nd S h ip Archaeo logy . D e ta i ls o f t h is o rgan isa t ior i4may b e o b ta ined f ro m t he Archaeo log ica l R esearch C en tre , N a t iona l Mar i t i me Museu m , Greenw ich , London S E10 9 NF .
3 09
GLOSSARY T h is G lossary i s r eprin ted f ro m Archaeology o f t he B oa t b y B asi l Greenh i l l . A . &C . B lack , 1 976 .
B oa tbu i ld ing t er ms a re n o t s tandard ised i n B r i ta in : word d i f feren t ly f ro m Wessex .
E ssex w i l l i n terpre t a
I n a dd i t ion , t he s a me p ar ts o f ab oa t o r t he
s a me b oa tbu i ld ing t echn ique may b e k nown b y d i f feren t n a mes i n d i f feren t c oun t ies. T h is g lossary i s b ased o n t he g lossar ies i n Er ic McKee 's C lenched L ap o r C l inker , a nd S ean McGra il 's Bu i ld ing a nd Tr ia ls o f t he Rep l ica o f a n Anc ien t Boa t .
b au lk
at ree t runk wh ich h as
c arve l b u i ld
b een r ough ly s quared . b eve l
t icu lar , t h is t er m i s s o me-
as ur face wh ich h as b een
t imes t aken t o b e s ynony mous
a ng led t o make a f i t w i th
w i th s ke le ton b u i ld w i th f lush-
a no ther . b lind f as ten ing
t here a re s evera l
d e f in i t ions i n u se ; i n p ar-
l a id s trakes. o ne i n wh ich t he
T he t er m i s
c on fused a nd i l l d ef ined.
p o in t o f t he n a i l d oes n ot p ro trude t hrough t he t imber . b ot to m b oards
c au lk
l eng ths o f t imber
t o i nser t ma ter ia l b e tween
t wo me mbers a f ter t hey h ave
f astened t oge ther a nd l a id
b een a sse mb led , a nd t hus
o ver t he b o t to m o f ab oa t
make t he j unc t ion wa ter t igh t
a s f loor ing .
( see l u t ing ) .
b ra i l
r ope u sed t o b und le a
c h ine b ea m
l ong i tudina l s treng th
f ore-and-a f t s a i l r ap id ly .
me mber f i t ted a t t he t urn o f
I t may b e r igged s ing ly o r
t he b i lge a nd i n to wh ich t he
w i th o thers , g enera l ly o n
p lank ing i s r abbe ted a nd f as-
b oo m less s a i ls t ha t h ave
t ened a bove a nd b e low .
t he ir p eaks e x tended b y a
a n a ng le i s f or med , t h is i s
s pr i t o r as tand ing g a f f ,
k nown a s ah ard c h ine , a nd
wh ich a re n ot r ead i ly
i s u sua l i n ' V '-bo t to m d esigns.
l owered .
c lench , r ive t
I n wooden s h ips a
n o t d raw o u t -u sua l ly d one
s tou t k nee f i t ted i n tern a l ly a cross t he b ows , h o ld ing t he s ides t oge ther
T o d e for m t he e nd
o f af asten ing s o t ha t i tw i l l
b reasthook , s te m lock , f ore h ook .
I f
o ver a r ove . c l inker b u i l t
af or m o f b oa t-
b u i ld ing i n wh ich t he s trakes
I n b oa ts t h is k nee i s a t
a re p laced s o t ha t t hey p ar t ly
g unwa le l eve l .
o ver lap o ne a no ther - u sua l ly u pper s trake o u tboard o f l ower
3 11
s trake , b u t o ccas iona l ly
c hanges i n d irec t ion .
t he r everse a rrange men t
T he l i nes o f ab oa t a re
i s f ound .
f a ir when t he l eve l l i nes , h al f b read ths , b u t tock
c onstruc t ion p lan a s ca le d rawing o f ab oa t w i th a
l ines a nd d iagona ls , b e ing t he mse lves f a ir , a l l c or-
l ong i tud ina l s ec t ion , h or i-
r espond .
z on ta l p lan , a nd s evera l t ransverse s ec t ions .
T he
f a ir ( v )
t o r ender a s e t o f l ines
p osi t ion a nd n a ture o f t he
e yeswee t a nd mu tua l ly t rue
s car fs , a nd o ther i mpor-
o n as h ip 's d raugh t .
t an t c onstruc t iona l d e tai ls a nd s can l ings ,
may a lso
b e g iven .
f ea ther-edge f l oor
f ro m t urn o f b i lge t o t urn o f b i lge , a nd s e t a ga ins t
h o ld t he l u t ing b e tween t wo
t he p lank ing .
s trakes. Ad ev ice
f or h old ing e le men ts o f a
f ra me a t ransverse me mber made u p o f more t han o ne p iece o f t imber , u sua l ly
b oa t t oge ther t e mporar i ly . c rook
e x tend ing f ro m s heer t o
ac urved p iece o f wood
s heer a nd s e t a ga ins t t he
wh ich h as g rown i n to a s hape u se fu l f or b oa tb u i lding . d agger p la te
at ransverse me mber -
o f ten a c rook - e x tend ing
c ove , s cot ia. A h o l low s haped mou ld ing . May b e u sed t o
c ra mp , c la mp , g r ipe.
t aper ing t o n o th ing .
p lank ing ( see r ib a nd t imber ) . f u t tock
a ny o f t he t imbers u sed
t o make u p af ra me i n a a me ta l r e trac-
wooden s h ip .
More e x-
t able d ev ice o n t he c en tre-
a c t ly , n o t t he f l oor o r t op
l ine f or c o mba t ing l ee-
t imbers .
way . d ol ly
g arboard
a me ta l b i l le t h e ld a ga ins t
t he h ead o f ab oa t n a i l wh i ls t i ti s b e ing c lenched . d oub le-ended
ab oa t wh ich i s
( near ly ) s y m me tr ica l a bou t
g ro m me t s trand(s ) o f r ope l ayed u p i n t he f or m o f ar ing . g unwa le
e dge o f t he s heer s trake o f
I tw ou ld
a n o pen b oa t .
n o t b e n or ma l u sage t o d es-
b er o r a rrange men t o f t im-
e nded .
b ers t ha t make u p t he s heer
d rop-kee l , c en tre b oard o r A wood o r
me ta l r e trac tab le d ev ice
l ine . h og
al ong i tud ina l s treng th me mb er o f ab oa t f astened t o t he
o n t he c en treline f or
t op o f t he k ee l t o p rov ide a
c o mba t ing l eeway . f a ir ( n )
I n o pen b oa ts ,
ma in ly p osi t iona l -t he t im-
c r ibe a p ra m a s d oub le-
c en tre p la te .
al ong i tudina l me mber
f i t ted r ound t he i ns ide t op
t he t ransverse a x is -p oint ed a t b o th e nds.
t he s trake n ex t t o t he
k ee l o r k ee l p lank .
l and ing f or t he i nner e dge o f
al i ne i s f a ir when i t
t he g arboard b e tween t he f or-
p asses t hrough i t s g u ide
ward a nd a f t d eadwoods .
marks w i thou t a ny a brup t
af or m o f d is tor t ion wh ich
3 12
A lso
c auses t he e nds o f ab oa t
s ec t ion o f a n o ar b e tween
t o d rop .
t he l oo m a nd t he b lade i s
h orn
c a l led t he s ha f t .
t o c heck t he s quareness o f a mou ld , r e la t ive t o t he
l u t ing
b oa t 's c en trel ine . j ogg le
u sed b e tween t wo a d jacen t
t o c u t o u t an o tch i n a
me mbers .
p iece o f t imber s o t ha t i t
ma ter ia l i nser ted b e tween
a nother me mber .
t wo me mbers b e fore t hey a re
t he ma in l ong i tud ina l s treng th me mber , s car fed t o t he s te mpos t f orward
a sse mb led . mast s tep
an a tura l ly g rown c rook
e xpressed a s ap ercen tage o f t he we igh t o f o ven d ry-
r igh t a ng les t o e ach o ther
wood .
o r more . t ha t p ar t o f as trake wh ich
mou lds
t he b ody p lan .
t o d raw o u t t he l i nes o f
ab oa t f u l l s ize .
mou ld l o f t
( see l i nes ) .
l o f t w i th a l eve l led
f loor o n wh ich t he l i nes o f
t he i n terre la t ion o f s ec-
av esse l a re d rawn o u t f u l l
t i ons i n d i f feren t p lanes wh ich s how t he s hape o f a T hey u sua l ly
s ize a nd f a ired . mou ld ing
b read th p lan w i th
ap a t tern o r l i near d ec-
o ra t ion c u t i n to a l eng th o f
c ons ist o f ( a ) s heer p lan w i th l ong i tud ina l s ec t ions ,
( a ) half
t ransverse wooden p a t-
t erns t ak ing t he ir s hape f ro m
i m med ia te ly a bove i t .
b oa t 's h u ll .
Thus t he f igure c an
b e g rea ter t han 1 00% .
i s o ver lapped b y t he s trake
l ines
t he we igh t o f
wa ter i n as peci men o f wood
u sed a s ab racke t b e tween
l ay-o f f
f i t t ing u sed t o l oca te
moisture c on ten t
t wo me mbers s e t a t a bou t
l and
( see c au lk ) .
t he h ee l o f a mast .
a nd t he p os t a f t . k nee
I n t h is t ex t t he
t er m i s u sed t o d escr ibe a ny
w i l l f i t c lose a ga ins t
k ee l
t rad i t iona l ly , l u t ing i s a
p las t ic s ubstance s uch a s p a in t
t imber . p ay
c over c au lk ing i n s ea ms w i th
wa ter l ines o r h or izon ta l
al ayer o f h o t p i tch .
s ec t ions , ( c ) b ody p lan w i th
b u t c o m mon ly u sed - t o c oa t
t ransverse s ec t ions.
as h ip 's b ot to m w i th t ar .
D ia-
g ona l l i nes , l ong i tud ina l s ec t ion l ines o n t he h a lfb read th p lan , a nd wa terl ines o n t he s heer p lan , e nab le t he t hree p lans t o
p lank
r abbe t , r abet , r ebate. A g roove o r c hanne l worked i n a me mb er t o a ccep t a no ther , w i thou t
a nd c hecked f or f a irness . b ers a re k nown a s aT ab le
al i p b e ing f or med . r ays
o u t f ro m t he c en tre o f at ree
t ha t p ar t o r a n o ar i n-
b oard o f t he p oin t o f p ivo t ; i ti nc ludes t he g r ip .
l ayers o f p arenchy ma c e l ls i n h or izon ta l s trands r unn ing
o f O f fse ts. l oo m
ac o mponen t o f as trake
t ha t i s n o t a l l i n o ne p iece .
b e r e la ted t o e ach o ther L ines c onver ted t o n u m-
L oose ly
T he
t owards t he c ircu m ference . r ib
as i mp le f or m o f f ra me .
T h is
t er m may b e more a ppropr ia te 3 13
c lo thed i n a' sk in ' o f p lank ing .
t han f ra me , when a pp l ied t o
S ke le ton a nd s he l l c ons truc t ion
sma l l o pen b oa ts .
merge i n to o ne a no ther w i th t he
r ove , r oove. A washerl ike p iece o f me ta l , wh ich i s
u se o f ' i n ter med ia te me thods ' o f u ncer ta in a ge .
f orced o ver t he p oin t o f a n a i l b e fore i ti s c lenched . s car f , s carph , s carve.
s pa l l
b u i ld ing t o b race p ar ts o f t he
A t a-
b oa t f ro m f loor , r a f ters o r
p ered o r wedge s haped j oin t
o ther s trong p o in t .
b e tween p ieces o f s im i lar s ec t ion a t t he j o in . s cr ive o r s cr ieve b oard
S pan ish w ind lass t he
men ts c loser t oge ther , a nd h o ld ing t he m t here .
( more f requen t ly ) ab oard e rec ted i n t he o pen a ir f or
s pi le
t he s a me p urpose .
f la t , w i l l g ive t he s hape t o c u t t he l ower e dge o f ap lank
i n wood , u sua l ly d ur ing E xa mp les a re :
t o t ransfer a c urved l i ne o n
t o ap a t tern wh ich , when l a id
ac rack o r s p l i t f or m ing
d ry ing o r s eason ing .
as i mple r ope a nd
r od d ev ice f or f orc ing t wo e le-
f loor o f t he mou ld l o f t o r
s hake
al igh t b a t ten u sed d ur ing
s ta t ion
c up s hakes
t he h or izon ta l p osi t ion o f
t he t ransverse s ec t ions o n t he
-c urved c le f ts b e tween t he
l ines .
g row th r ings ;
l i nes when b u i ld ing f ro m d rawi ngs , a nd mou lds a re g enera l ly
h ear t s hakes
-s p l i ts r ad ia t ing f ro m t he c en tre o f at ree . s heer , s heer l i ne.
made o f t ransverse s ec t ions a t s o me o r a l l o f t hese s ta t ions .
T he c urve
o f t he u pper e dge o f t he
s tea ler
h u l l .
at apered p lank o r p la te
worked i n to t he e n try o r r un
s heer s trake
o f av esse l t o p reserve t he
t he t op s trake
g enera l l i e o f t he s trakes w i th-
o f p lank ing . s he l l c ons truc t ion
o u t mak ing t he e nds t oo t h ick a me thod o f
b oa tbu i ld ing i n wh ich t he s he l l ( i .e . t he wa tert igh t e nve lope o f s te ms , k ee l a nd
o r t h in . S tockho lm t ar a b lack ish s em il i qu id p repared b y t he d est ruc t ive d ist i l la t ion o f v ar ious
p lank ing ) i s b u i l t o r p ar t ly
t rees o f t he P inaceae f am i ly .
b u i l t b e fore t he r ibs a nd o ther i n terna l s treng then ing me mb ers a re f i t ted ( see s ke le ton
s tocks s e t-up . T he t e mporary wooden s uppor t o n wh ich a b oa t
c ons truc t ion ) . s hrouds
T hey a re u sed a s d a tu m
i s b u i l t .
r opes l eading f ro m t he
s trake
as ing le p lank o r c o mbin-
mas thead t o t he s ides o f t he
a t ion o f p lanks wh ich s tre tches
b oa t t o s uppor t t he mast a th-
f ro m o ne e nd o f ab oa t t o t he
war tsh ips .
o ther .
s ke le ton c onstruc t ion
a me thod o f
s tre tcher
a n a thwar tsh ips l eng th
b oa tbu i ld ing i n wh ich a f ra me-
o f t imber a ga inst wh ich a
work o f s te ms , k ee ls a nd r ibs
r ower b races h is f ee t .
i s f irst e rec ted , o r p ar t ly e rec ted .
Th is s ke le ton i s t hen 3 14
t e mp la te a s haped p a t tern o f a n e le men t o r s ec t ion o f ab oa t ,
t imber
made o f p lywood o r h ard-
May a lso b e u sed
g enera l ly r e ferr ing t o a ny p iece o f wood u sed i nb oa tb u i ld ing . One p iece r ibs
b oard e tc . t ho le a p in p ro jec t ing u pwards a t s heer l eve l t o p rov ide
o r f ra mes , e spec ia l ly t hose s teamed o r b en t i n to p lace ,
ap ivot f or a n o ar . S tr ic t ly t ho le-p in , b u t f requen t ly
a re f requen t ly c a lled t imbers .
u sed a s a bove . t hwar t
a n e le men t o f af ra me
o r r ib .
t rena i l , t reena il , t runne l. Wooden p eg o r t hrough f asten ing u sed t o j oin t wo me mbers . I t may b e s ecured a t e ach o r e i ther e nd b y t he i nser-
at ransverse me mber
u sed a s as ea t .
t i on o f a wedge .
T he a dd i t iona l t er ms b e low a re t aken f ro m T he N or th F err iby B oa ts b y E .V . Wr igh t . b i lge
( Na t iona l Mar i t i me Museum Monograph N o . 2 3 ) .
t he c urved s ur face b e tween
h ogg ing t russ
t he b ot to m a nd t he s ides o f
r ope a t tached ( genera l ly b y p assing r igh t r ound t he h u l l ) a t b ow a nd s tern a nd t igh tened
ab oa t . c lea t
u p b y o ne o r more p rops am idsh ips ( t hree i n t he c ase
t he i n tegra l p er fora ted
b locks a nd r idges o f v ar ied
o f t he a nc ien t Egyp t ian e xamples ) . I t s p urpose i s t o
s hape l ef t s tand ing o n t he s ur face o f t he p lanks w hen
p reven t t he h u l l o f ab oa t f ro m f rac turing ( h ogg ing ) when t he midsh ips s ec t ion i s s up-
t hey w ere h ewn o u t o f t he s o l id t imber . T hese ' c lea ts ' c ou ld b e u sed t o s ecure t he
p or ted o n a wave a nd t he b ow a nd s tern a re u nsuppor ted .
t ransverse b ars o r , i ft he i n terpre ta t ion i s c orrec t , t he g ir th l ash ing . T he s a me d e f in i t ion i s c o m-
l a th
mon ly u sed f or t he s im i lar
an arrow s tr ip o f wood , u sed i n t he N or th F err iby b oa ts f or c apping t he s eams a nd p reven t ing t he l u t ing ( moss ) f ro m b e ing washed
f ea tures o n t he p lanks o f N orse s h ips. g ir th-lash ing
ah eavy l eng thw ise
ab ind ing o f r ope o r
o u t .
s im i lar ma ter ia l a round t he
s eam
g ir th o f ab oa t t o h o ld t he
t he j unc ture o f t wo me m-
b ers r equ ired t o b e wa ter t igh t .
p lanks t oge ther .
s trake
g enera l ly a s ing le p lank
o r c o mb ina t ion o f p lanks wh ich s tre tches f ro m o ne e nd o f ab oa t t o t he o ther . Iu se t he t erm h ere o n ly f or t he p lanks o f t he s ides , n o t t he b o t to m o f t he N or th F err iby b oa ts. 3 15