Science and Archaeology, Glasgow 1987, Parts i and ii: Proceedings of a conference on the application of scientific techniques to archaeology Glasgow, September 1987 9781407390093, 9781407390109, 9780860545811, 9781407318165

Table of contents :
Cover Page
Copyright Page
Preface
List of Contributors
Table of Contents
PART I
Ceramics & Lithics
Metals
Part II
Cover Page
Copyright Page
Table of Contents
Organics
Prospection
Computing & Statistics
Dating

Citation preview

Science and Archaeology Glasgow 1987 Proceedings of a conference on the application of scientific techniques to archaeology Glasgow, September 1987

Part i

edited by

Elizabeth A. Slater and James 0. Tate BAR British Series 196(i) 1988

B.A.R.

122 Banbury Rd, Oxford, OX2 7BP, UK

GENERAL EDITORS A.R. Hands, B.Sc., M.A., D.Phil. D.R. Walker, M.A.

BAR -B196(i), 1988:

'S cience and Archaeology, Glasgow 1987' , Part i

© The Individual Authors, ,1988 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 9781407390093 (Volume I) paperback ISBN 9781407390109 (Volume II) paperback ISBN 9780860545811 (Volume set) paperback ISBN 9781407318165 (Volume set) e-format DOI https://doi.org/10.30861/9780860545811 A catalogue record for this book is available from the British Library This book is available at www.barpublishing.com

P REFACE

M any p eople i n B ritain i nvolved w ith t he a pplication o f s cientific t echniques i n a rchaeology h ave f ound d ifficulty i n o btaining f unds t o t ravel t o t he I nternational Symposia o n A rchaeometry, a nd t he A rchaeological S cience C ommittee o f t he C PA p roposed t hat a s maller s cale a rchaeometry c onference s hould b e h eld i n B ritain . T his i dea o f a f orum f or d iscussion w as t aken u p b y t he G lasgow A rchaeology D epartment i n 1 986 a nd a c onference w as a rranged f or S eptember 1 987, o rganised b y r epresentatives f rom t hree m ain c entres i n S cotland. W e h oped t hat t he m eeting w ould p articularly i nclude p apers b y y oung w orkers , b oth s cientists a nd a rchaeologists , o n t heir o wn r esearch , a s w ell a s r eview p apers b y e stablished w orkers i n s pecialist f ields . O n t he w hole t his t urned o ut t o b e t he c ase a nd , a lthough t he p apers w ere p redominantly f rom s cientists , t here w as c onsiderable i nterdisciplinary d iscussion d uring t he c onference . D etails o f a ll t he p apers a nd p osters p resented a re i ncluded i n t his p ublication; s ome b eing r epresented b y a bstracts a s t he d etailed r esults a re t o b e p ublished e lsewhere. T he o rganisation o f t he c onference i nvolved a l arge n umber o f p eople . W e s hould l ike t o t hank e specially H elen G arland, P aul W ilthew , A manda C lydesdale a nd N orma W äkeling f or h elp i n t he o rganisation a nd d uring t he m eeting; t o A listair A uld, N orman T ennent, R osemary W att, J ames T hompson a nd t he s taff a t t he B urrell m useum f or t he o rganisation o f t he f irst r eception; P rofessor F rank W illett a nd s taff a t t he H unterian Museum f or t he o rganisation o f t he s econd r eception; t he U niversity o f G lasgow f or a g enerous c ontribution t o t he c osts o f t he H unterian R eception ; t he R oyal B ank o f S cotland f or t he p rovision o f d ocument c ases a nd P rofessor L eslie A lcock a nd t he D epartment o f A rchaeology , G lasgow U niversity f or t heir g enerous s upport f or t he C onference a nd p ublication . F inally t he e ditors - L iz S later a nd J im T ate - w ould l ike t o t hank c olleagues w ho h elped i n t he e diting o f p articular p apers , e specially D avid S anderson, h ut a lso H elen G arland, A ndrew K itchener a nd P en T orsney .

C ONFERENCE O RGANISERS E . S later G lasgow U niversity

J . T ate N ational M useums o f S cotland

D . S anderson S cottish U niversities R esearch & R eactor C entre

L IST OF C ONTRIB MORS

A dams F .

U niversity o f A ntwerp au m, B -2610 W ILRIJK, B elgium

U niversiteitsplein,

1 ,

A itchison T .C.

D epartment o f S tatistics, GLASGOW G 12 8 00

A itken M .J.

R esearch L aboratory f or A rchaeology , O XFORD OX1 303

A ntoine S .E.

D epartments o f A rchaeology a nd C hemistry , U niversity C ollege C ardiff , C ARDIFF C F1 1 YL

Aspinall A .

S chool o f A rchaeological S ciences, University o f B radford, B RADFORD B D7 1 DP

A tik S .

A rchaeological M useums o f I stanbul,

B ailiff I .K.

Department of Archaeology , Durham University , 4 6, S addler S treet , D URHAM D H1 3 NU

P a n ne M .G.L.

Palaeoecology Centre, Q ueen 's University, B ELFAST P T7 1 NN

B artosiewicz L .

A rchaeological I nstitute o f t he H ungarian A cademy o f S ciences, H -1250 B UDAPEST , U ri u .49, H ungary

B axter M .S.

S cottish U niversities ' R esearch F AST K ILBRIDE , Glasgow C 75

B ayley J .

Ancient Monuments L aboratory, E nglish H eritage, F ortress H ouse, 2 3, S avile R ow , LO SIMI J W 1X 2 HE

B ell M .A.

R esearch C entre f or C omputer A rchaeology , D epartment o f . Computing, North Staffordshire Polytechnic, B lackheath L ane, S TAFFORD

B ellerby T .J.

Department of Geology, S HEFFIELD S 10 2 TN

B hattacharya S .K.

P hysical

U niversity o f Glasgow,

a nd

6 ,

K eble R oad,

I STANBUL, T ürkey

R eactor

C entre,

University o f S heffield,

R esearch L aboratory,

AHMEDEBAD 3 80 0 09,

I ndia B ie l < L

Department

of

Civil

Fnqineering,

The

City

U niversity , L ONDON E C1V O RB B oucher A .

S chool o f A rchaeological S ciences, U niversity o f B radford, B RADFORD B D7 1 DP

i i

B ourner S .

D epartment o f C hemistry , U niversity C ollege C ardiff , C ARDIFF C F1 1 XL

B ranigan K .

D epartment o f A rchaeology a nd P rehistory , U niversity o f S heffield, S HEFFIELD S 10 2 TN

B rooks I .P.

D epartment o f A rchaeology a nd P rehistory , U niversity o f S heffield, S HEFFIELD S 10 2 TN

B rown D .M.

P alaeoecology C entre, Q ueen 's U niversity , B ELFAST E7 1 NN

C handratillake M .R .Department o f C hemistry , M ANCHESTER

U niversity o f M anchester,

C hapman P .

S chool o f A rchaeological S ciences, U niversity o f B radford, B RADFORD P D7 1 DP

C lark P .

S cottish U niversities ' R esearch a nd R eactor C entre, E AST K ILBRIDE , G lasgow G 75

C oles G .M.

D epartment o f A rchaeology , G eorge S quare , U niversity o f E dinburgh , E DINBURGH

C ook G .T .

S cottish U niversities ' R esearch a nd R eactor C entre, E AST K ILBRIDE , G lasgow G 75

C raddock P .T.

R esearch L aboratory , T he B ritish Museum , L ONDON W C1P 3 DG

D algleish G .R.

National Museums E DINBURGH E H2 1 JD

D avies G .R.

D epartment o f C hemistry , U niversity C ollege C ardiff , C ARDIFF C F1 1 XL

D ockrill S .J.

S chool o f A rchaeological S ciences, U niversity o f B radford, B RADFORD P D7 1 DP

D resser P .O.

D epartment o f Plant S cience, C ardiff, C ARDIFF C F1 1 XL

E vans J .

D epartment o f P hysical S ciences, N orth E ast L ondon P olytechnic, R omford R oad, L ONDON E 15 2 4LZ

E vans J .C.

D epartment o f A rchaeology , C ardiff, C ARDIFF C F1 1 XL

F abrizi M .

1 01, W oodland W ay, W 1nchmore H ill, L ONDON N 21 3 PY

G abra-Sanders T .

1 8, C raigleith H ill P ark, E DINBURGH E H4 2 NR

G affney C .

S chool o f A rchaeological S ciences, U niversity o f B radford, B RADFORD B D7 1 DP

i ii

of

S cotland,

Queen

Street,

U niversity College

U niversity

C ollege

G ale D .

S chool o f Archaeological S ciences, U niversity o f B radford, B RADFORD P D7 1 DP

G arland A .N.

D epartments o f P heumatology & P athology , S topford B uilding, O xford R oad, M ANCHESTER M 13 9 PT

G arland H .F.

D epartment o f Conservation & Analytical R esearch, National Museums o f S cotland, Chambers S treet, E DINBURGH E H1 1 JF

G ater J .G.

S chool o f A rchaeological S ciences, U niversity o f B radford, BRADFORD B D7 1 DP

G entles D .S.

Department of Geological P olytechnic, P LYMOUTH P L4 8 AA

G illings M .

S chool o f A rchaeological S ciences, U niversity o f B radford, B RADFORD B D7 1 DP

G opalan K .

National 5 00 0 07,

G roves C .

G eophysical

Sciences,

Plymouth

R esearch I nstitute, H YDFRABAD

I ndia

D epartment

o f

A rchaeology

& P rehistory ,

U niversity

o f S heffield, S HEFFIELD S 10 1 DP H arkness D .D.

N .E.R.C.

H art F .A.

Chemistry Department, Q ueen Mary College, L ondon U niversity, L ONDON

H enderson J .

R esearch L aboratory f or A rchaeology a nd o f A rt, 6 , K eble R oad, O XFORD O X1 1 YL

H eron C .

D epartment o f C hemistry , U niversity C ollege C ardiff , C ARDIFF C F1 1 XL

H eyworth M .

A ncient Monuments L aboratory, E nglish H eritage, F ortress H ouse, 2 3, S avile R ow , L ONDON W1X 2 HE

H ill H .F.

D epartment o f t he Human E nvironment, I nstitute o f A rchaeology, 3 1-34, G ordon S quare, L ONDON W C1

H illam J .

D epartment o f A rchaeology & P rehistory , o f S heffield, S HEFFIELD S 10 1 DP

U niversity

H ook D .P.

R esearch L aboratory , T he B ritish M useum , 3 DG

L ONDON W C1B

H unt C .O.

S chool o f G eography , C ambridgeshire C ollege o f A rts a nd T echnology, C AMBRIDGE C B1 1 PT

H unter J .R.

S chool o f A rchaeological S ciences, U niversity o f B radford, B RADFORD B D7 1 DP

J anaway P .C.

S chool o f A rchaeological S ciences, U niversity o f B radford, B RADFORD R D7 1 DP

1 4

C L aboratory, E AST K ILBRIDE, G lasgow G 75

i v

t he H istory

J ones R .

D epartment o f A rchaeology , C ardiff, C ARDIFF C F1 1 XL

J ones R .F.J.

S chool o f A rchaeological S ciences, U niversity o f B radford, B RADFORD B D7 1 DP

L a N iece S .

R esearch L aboratory , T he B ritish Museum , L ONDON W C1B 3 DG

L eese M .

R esearch L aboratory , T he B ritish M useum , L ONDON W C1B 3 DG

M acSween A .

S chool o f A rchaeological S ciences, U niversity o f B radford, B RADFORD B D7 1 DP

M ackay W .I.

1 30, M archmont R oad, E DINBURGH E H9 l AQ

M ain P .L.

R esearch L aboratory , T he B ritish M useum , L ONDON W C1P 3 DG

M anning W .H.

D epartment o f A rchaeology , C ardiff, C ARDIFF C F1 1 XL

M cDonnell J .G.

Ancient Monuments L aboratory, E nglish H eritage, F ortress H ouse, 2 3 S avile R ow , L ONDON W 1X 2 HE

M ills C .

c /o C entral E xcavation U nit, H istoric B uildings a nd Monuments, S DD, 9 Melvil l e S treet, E DINBURGH E H3 7 OD

M offat P .

S HARP,

N eedham S .P.

D epartment of Prehistoric and Romano-British A ntiquities, T he B ritish M useum , L ONDON W C1B 3 DG

N ewton G .W.A.

D epartment o f C hemistry , University o f Manchester, M ANCHESTER

N oel M .

D epartment o f G eology , S HEFFIELD S 10 2 TN

N orthover J .P.

D epartment o f Metallurgy a nd S cience o f Materials , U niversity o f O xford, P arks R oad, O XFORD

O ladipo M .

D epartment o f Chemistry, U niversity o f M anchester, M ANCHESTER

O ttaway B .S.

S chool o f A rchaeological S ciences, U niversity o f B radford, B RADFORD B D7 1 DP

P lacido F .

D epartment of Physics, Paisley College T echnology , H igh S treet , P AISLEY P A1 2 BE

P ollard A .M.

D epartment o f C hemistry , U niversity C ollege C ardiff , C ARDIFF C F1 1 XL

U niversity

U niversity

C ollege

C ollege

3 6 H awthorndale, E DINBURGH

U niversity o f S heffield,

of

P owers A .

D epartment o f A rchaeology & P rehistory , o f S heffield, S HEFFIELD 5 10 2 TN

R amesh

P hysical R esearch L aboratory, AHMEDEBAD 3 80 0 09, I ndia

R .

U niversity

R hodes E .J.

R esearch L aboratory f or A rchaeology , O XFORD O X1 3 0J

R ingrose T .J.

D epartments of P robability a nd Statistics& A rchaeology a nd P rehistory , U niversity o f S heffield , S HEFFIELD S 10 2 TN

R itchie M .

D epartment o f S tatistics, G LASGOW G 12 8 Q0

R oberts C .A.

C alvin Wells L aboratory , S chool o f A rchaeological S ciences , U niversity o f B radford, B RADFORD B D7 1 DP

R obinson V .J.

D epartment o f C hemistry, U niversity o f M anchester, M ANCHESTER

S anderson D .W .C.

S cottish U niversities ' E AST K ILBRIDE G lasgow G 75

S cott E .M.

D epartment o f S tatistics, U niversity o f G lasaow, GLASGOW G 12 8 00

S hearer G .L.

D epartment o f O bjects C onservation, T he Metropolitan M useum o f A rt , 5 th Ave a t 8 2 n d S t , N EW Y ORK N Y10028 U .S.A

S later E .A .

D epartment o f A rchaeology , U niversity o f G lasgow , G LASGOW G 12 8 00

S mith B .W .

R esearch L aboratory f or A rchaeology , O XFORD O X1 3 QJ

S mith D .M.

G eology D epartment , R oyal H olloway a nd B edford N ew C ollege, L ondon U niversity , L ONDON

S poerry P .

Archaeology Unit, Dorset E ducation, P OOLE B H12 5 BB

S trickertsson K .

D epartment of P hysics, P aisley College T echnology , H igh S treet , P AISLEY P A1 2 BE

S ymonds P .P.

C olchester A rchaeological T rust, C OLCHESTER

T akäcs-Bir6 K .

A rchaeol o gical I nstitute o f t he H ungarian A cademy o f S ciences, H -1250 B UDAPEST, U ri u .49, H ungary

T arling P .H.

Department of Geological P olytechnic, P LYMOUTH P L4 8 AA

v i

6 ,

K eble R oad,

U niversity o f Glasgow ,

R esearch a nd R eactor C entre

6 ,

I nstitute

Sciences,

K ehle R oad,

o f

H igher

of

Plymouth

T ate J .O.

N ational Museums E DINBURGH E F T1 1 JF

T ite M .S.

R esearch L aboratory , T he B ritish M useum , L ONDON W C1P 3 DG

T örsnev B .

D epartment o f S tatistics, G LASGOW G 12 8 00

T Uerul P .

I nstitute f or N uclear E nergy , o f I stanbul, I STANBUL, T urkey

V an E spen P .

U niversity o f A ntwerp M A ), B -2610 W ILRIJK , B elgium

U niversiteitsplein,

1 ,

W ales S .

D epartment o f Human E nvironment, I nstitute A rchaeology, U niversity C ollege, L ONDON W C1H O PY

o f

Walker R .

GEOSCAN R ESEARCH, Heather B rae, Chrisharben P ark, C layton, B RADFORD B D14 6 AE

Walsh J .N.

G eology D epartment , C ollege,

o f

S cotland,

R oyal

Chambers

S treet,

U niversity o f Glasgow,

T echnical

U niversity

H olloway a nd B edford N ew

L ondon U niversity, L ONDON

Warren S .E.

S chool o f A rchaeological S ciences, University o f B radford, B RADFORD P D7 1 DP

W hitbread I .K.

D epartment o f A rchaeology , S outhampton U niversity , S OUTHAMPTON

W hittle A .W .R.

D epartment o f A rchaeology , C ardiff, CARDIFF C F1 1 YL

W ilcock J .D.

R esearch C entre f or C omputer A rchaeology , D epartment o f Computing, North Staffordshire Polytechnic, B lackheath L ane, S TAFFORD

Willett F .

H unterian Museum , U niversity o f Glasgow , GLASGCW G 12 8 0Q

W illiams R .

D epartment o f C hemistry , U niversity C ollege C ardiff , C ARDIFF C F1 1 YL

W ilthew P .T .

National Museums E DINBURGH E H1 1 JF

Wouters H .

U niversity o f A ntwerp ( UIA ), P -2610 WILRIJK, B elgium

v ii

o f

University College

S cotland,

Chambers

S treet,

U niversiteitsplein,

1 ,

T ABLE OF C ONTENTS P ART i Q uestions, a nswers a nd t he c onsumer i n a rchaeological s cience.

1

T ite M .S.

T he s tudy o f a ncient c eramic t echnologies: p ast a chievements a nd f uture p rospects.

9

H eyworth M .P., H unter J .R., W arren S .E. & Walsh J .N.

T he a nalysis o f a rchaeological m aterials u sing i nductively c oupled p lasma s pectrometry .

J ones R .F.J.

C ERAMICS & L ITHICS

2 7

A nalysis o f R oman p ottery f rom C olchester 4 1 S mith D .M., H art F .A., S ymonds P .P. & W alsh J .N . b y i nductively-coupled p lasma s pectrometry . P ollard A .M . &B ourner S . A c hemical a nd m ineralogical s tudy o f N antgarw p orcelain.

5 7

N ewton G .W .A ., R obinson C lay s ources a nd C orinthian a mphorae. • O ladipo M ., C handrat illake M .P. & W hitbread I. K. C eramic p rovenance b y t race e lements: t he c urrent s ituation.

5 9

8 2

R eview o f s tatistical p rocedures i n p ottery p rovenance.

8 2

N eutron a ctivation a nalysis o f l ate N eolithic p ottery f rom C zechoslovakia a nd B avaria.

8 3

M acSween A ,, H unter J .R. &W arren S .F.

A nalysis o f c oarse w ares f rom t he O rkney I slands.

9 5

S poerry P .

P roblem-specific p rovenance - a c ase s tudy f rom m edieval W essex.

C hapman B ., J anaway P .C. &M acSween A .

R eview o f X -radiography o f p ottery w ith 1 21 e xamples f rom s everal E uropean p rehistoric s ites.

T i eul B .

E valuation o f a ncient o paaue g lasses b y X -radiography .

1 45

H enderson, J .

O pacifiers i n a ncient g lass: a nalytical c onsiderations.

1 53

B rooks I .P.

M icropalaeontology a nd f lint s ourcing.

B ell M .A.

&O ttaway B .S.

&A tik S .

v iii

s ome

1 07

1 55

T akgcs-Bir6 K .

P roblems i n t he c haracterization o f H ungarian l ithics.

1 57

M ETAL S C raddock P .T .

&G ale D .

E vidence f or e arly m ining a nd e xtractive 1 67 m etallurgy i n t he B ritish I sles: p roblems a nd p otentials.

B ayley J .

N on-ferrous m etal w orking: a nd c hange.

c ontinuity

J ones P ., M anning W .H . &P ollard A .M.

A c hemical a nd m etallurgical e xamination o f b rooches f rom R oman W ales.

2 09

W outers R ., V an E spen P . &A dams F .

E nergy-dispersive X -ray f luorescence a pplied t o B ronze A ge a rtefacts f rom t he H asse c ollection.

2 11

L eese M .N . &N eedham S .P. A n a nalytical s tudy o f e arly B ronze A ge m etalwork f rom s outhern E ngland.

1 93

2 21

N orthover J .P.

C opper, t in, s ilver a nd g old i n t he I ron A ge.

2 23

L a N iece S .

W hite i nlays i n A nglo S axon j ewellery .

2 35

S later E .A . &W illett F .

N eutron a ctivation a nalysis o f c lay c ores 2 47 f rom N igerian c astings.

N eedham S .P. & H ook D .P.

L ead a nd l ead a lloys i n t he B ronze A ge r ecent f inds f rom R unnymede B ridge.

W ilthew P .T., T ate J .O . &D algleish G .R.

A n X PF s urvey o f S cottish p ewter m easures 2 75

M cDonnell J .G.

O re t o a rtefact - a s tudy o f e arly i ronworking t echnology.

2 83

F abrizi M .

C opper c orrosion p roducts: a nd i nterpretation.

2 95

a nalysis

2 59

P art i i O RGANICS M ackay W .I. & G abraS anders T .

S ome t extile s amples f rom t he D oTartment o f A mazonas, P eru.

3 05

G abra-Sanders T .

U se o f s canning e lectron m icroscopy t o s tudy f ibres i n t extile r emains. D ye a nalysis a t t he N ational M useums o f S cotland.

3 13

C ontributions t o p alaeohistology .

3 21

G arland P .E.

G arland A .N.

i x

3 19

R oberts C .A.

T rauma a nd t reatment i n B ritish a ntiquity : a r adiographic s tudy .

3 39

B artosiewicz L .

B iometrics a t a n E arly M edieval b utchering s ite i n H ungary .

3 61

A ntoine S .F., D resser P .O., P ollard A .M. & W hittle, A .W .R.

B one c hemistry a nd d ietary r econstruction 3 69 i n P rehistoric B ritain: e xamples f rom W essex.

M offatt B .

F ield t ests f or M edieval d umps o f b lood a t S outra, M idlothian.

3 81

O rganic r esidues i n a n A nglo-Saxon g rave.

3 91

N ew p ossibilities o f o btaining a rchaeol ogical i nformation f rom c oprolites.

4 03

D avies G .R. A. M. W ales S .

&P ollard

&E vans J .

S hearer G .

C haracterization o f o rganic a rchaeo4 13 l ogical r esidues u sing d iffuse r eflectance F ourier T ransform i nfra-red s pectroscopy.

H eron C . &P ollard A .M.

T he a nalysis o f n atural r esinous m aterials f rom R oman a mphoras.

H ill H .E. & E vans J .

V egeculture i n S olomon I slands p rehistory 4 49 f rom p ottery r esidues.

P owers A .

P hytoliths: m ineral?

H unt C .O. & C oles G .M.

T he a pplication o f p alynofacies a nalysis t o g eoarchaeology .

4 73

W alker R .

G eophysical i nstrumentation f or a rchaeological p rospection.

4 85

D ockrill S .J., H unter J .R. & G ater J .G.

T he u se o f a pplied g eophysical t echniques 4 87 w ithin t wo e xcavation p rogrammes o n t he i sland o f S andy , O rkney .

G illings M . &B oucher A .

P robing t he R oman o ccupation o f t he N orth.489

A spinall A . &G affney C .

T he r ole o f t he S chlumberger a rray i n a rchaeological p rospection, w ith a n ote o n s ample p reparation a nd s torage o f c onducting a nomalies u sed i n s imulation e xperiments.

4 91

ellerby T .J. & N oel m ., B Y . B ranigan

P reliminary s tudies o f t hermal a rchaeol ogical p rospection.

4 95

a nimal, v egetable a nd

4 29

4 59

P ROSPEC I 'ION

C OMPU 'rING & S TATISTICS W ilcock J .D.

P ast a nd f uture d irections i n a rchaeol ogical c omputing.

M ain P .L .

A c omputer d atabase a t t he B ritish M useum 5 09 R esearch L aboratory f or h olding a rchaeom etric d ata.

R itchie M ., T orsney B . &W illett F .

O bjective a ssessment o f D ark's c hronology 5 19 o f B enin m emorial h eads.

R ingrose T .J.

E xploratory m ultivariate a nalysis o f s tratigraphic d ata: A rmstrong's d ata f rom P in R ole c ave r e-examined.

5 21

B iek L .

A rchaeology ,

5 41

s cience a nd D omesday .

4 97

D ATING B aillie M .G.L. & B rown D. M.

A n o verview o f o ak c hronologies.

5 43

M ills C .

D endrochronology : s hort o f i t.

5 49

G roves C .

&P illam J .

t he l ong a nd t he

T he p otential o f n on-oak s pecies f or t ree-ring d ating i n B ritain.

5 67

S cott E .M., B axter M .S., H arkness D .D., A itchison T .C. & C ook G .T .

T he c omparability o f r esults a cross a s ub-section o f r adiocarbon l aboratories.

5 81

R amesh R ., P hattacharya S .K. & G opalan K .

C limatic s ignificance o f v ariations i n t he w idth a nd s table i sotope r atios o f t ree r ings.

5 91

A itken M .J., S mith B .W . & R hodes E .J.

O ptical d ating:

6 11

B ailiff I .K.

T he D urham T L d ating s ervice.

6 13

S anderson D . &C lark P .

R ecent p rogress i n T L d ating o f S cottish c eramics a nd b urnt s tones.

6 23

p rogress r eport.

S trickertsson K ., T hermoluminescence d ating o f S cottish S anderson, D ., P lacido F . v itrified f orts: n ew r esults a nd a &T ate J .O . r eview .

6 25

W illiams R ., P ollard A .M. A n e lectron s pin r esonance s tudy o f & E vans J .C. m ollusc s hells f rom a rchaeological c ontexts.

6 35

G entles D .S. & T arling D. H.

A rchaeomagnetic d irectional d ating a nd m agnetic a nalyses w ith s pecial r eference t o aS cottish v itrified d un.

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QU WTIONS, ANSWERS AND THE CONSUMER I N ARCHAEOLOGICAL S CIENCE

P .F .J.Jones S chool o f A rchaeological S ciences, U niversity o f B radford, B radford

I n t his p aper I w ant t o e xamine t he k inds o f a uestions a nd a nswers w e g et i n a rchaeological s cience . I t s eems t o me t hat p ublished w ork i s t oo o ften t he r esult o f t echniques i n p ursuit o f p roblems . T his r aises g eneral i ssues a bout w hat w e a re d oing i n a rchaeological s cience , w hat w e s hould b e d oing , w hy a nd f or w hom . Iw rite f rom t he p oint o f v iew o f s omeone w ho w as t rained a s a n a rchaeologist , b ut w ho h as b een e ducated i n t he w ays o f a rchaeological s cience b y my c olleagues a nd s tudents d uring a d ecade i n t he B radford S chool o f A rchaeological S ciences . W e m ust r ecognise s ome b asic l imitations o f a rchaeological s cience . I n t he s ense t hat i t i s n ot a t t he t rue f orefront o f n ew s cientific r esearch , i t i s s econd c lass s cience ; i t i s n ot w orking a t t he l evel o f s plitting t he a tom o r u nderstanding D NA . I t i s u nlikely t hat t here w ill e ver b y aN obel P rize f or a rchaeological s cience, d ue b oth t o t he n ature o f t he p roblems t ackled a nd t o t he s cale o f r esources c ommitted . T he p roblems a re c ircumscribed b y t heir a rchaeological c onnection, w hilst t he r esources a vailable a re n ormally t oo l imited i n a rchaeological s cience i tself f or n ew t echniques a nd n ew i nstrumentation t o b e d eveloped s olely w ithin a rchaeological s cience . I t s hould n ot w orry u s t oo m uch t hat w e l ack t he i ntellectual s ex a ppeal o f i nternational s tar q uality s cience a s d efined h ere ; t he s ame i s t rue f or m ost s cientists , b ut t his d oes n ot m ean t hat t hey d o n ot d o v aluable w ork t o h igh s tandards . T he t rue t est o f t he v alue o f a rchaeological s cience i s h ow w ell i t d oes w hat i t i s s upposed t o d o . Q uestions i n a rchaeological s cience W hat t herefore i s a rchaeological s cience s upposed t o d o? P ow d oes i t d iffer f rom p hysics , c hemistry o r b iology? T he s imple a nswer m ust l ie i n i ts c onnection w ith a rchaeology a nd t he s tudy o f t he p ast s pecifically t he s tudy o f t he h uman p ast . T his p oses d istinct p roblems f or a rchaeological s cience, even c ompared w ith o ther a pplied d isciplines l ike e arth a nd e nvironmental s cience w ith w hich w e s hare m any w orking t echniques . A rchaeological s cience f orms p art o f t he v ery b road s tudy o f h uman b ehaviour, w here i t i s h ard t o a gree d efinitions o f t he c ontributions m ade b y h istory , a rchaeology a nd a nthropology ( c .f . D eetz, 1 988). T here c an b e n o e scape f rom t he d ifficulties b oth o f d ealing w ith m essy, u npredictable p eople a nd w ith t he n ature o f t he a rchaeological r ecord i tself . Y et i t i s t he m aterial n ature o f t he a rchaeological r ecord w hich g ives a rchaeological s cience i ts o pportunity . A rchaeol o gical r emains i n t hemselves a re i nadequate f or t he t asks w e w ish t o s et t hem . As herd o f p ottery i s n ot a n e xchange s ystem , b ut e nough s herds m ay p rovide u s w ith a w ay t o u nderstand

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e xchange s ystems , p rovided t hat w e e xtract t he m aximum i nformation f rom t he o bjects . S cientific t echniques a llow t he maximisation o f i nformation f rom t he d ata w hich n o a rchaeologist a mbitious f or u nderstanding c an i gnore . I t w as t he e xciting p rospect o f s uch e xpansions o f p ossibility t hat o pened f or m e, l ike m any o thers, w hen a s as tudent n early t wo d ecades a go I b ouaht m y c opy o f t he p aperback s econd e dition o f P rothwell a nd H iggs ' S cience i n A rchaeology ( Brothwell & H iggs, 1 969). T he b ook w as s ubtitled " A S urvey o f P rogress a nd P esearch" , a nd i t r evealed a v ery l arge a mount o f p rogress , b uilding o n t he r ather h aphazard a pplications o f s cience t o a rchaeology t hat h ad b ecome i ncreasingly c ommon f rom t he 1 930s o nwards . We s hould n ot f orget t hat i t w as t hen t hat t he L ondon I nstitute o f A rchaeology w as f ounded u nder Mortimer W heeler. I t i ncorporated c onservation a nd e nvironmental a rchaeology f rom t he b eginning , a nd s et t he p attern f or t he m odern a rchaeology d epartment ( Evans , 1 987 ). W e c annot b e t oo c omplacent t hat a rchaeological s cience i s s uch a y oung a nd t ender p lant w hich m ay e ventually f lower i nto f ully m ature p rofusion. I ts s eeds w ere p lanted i n t he e arly s tages o f t he d evelopment o f m odern a rchaeological p ractice, a nd w e h ave h ad l ong e nough t o e xpect t hat a w orthwhile c rop s hould h ave b een p roduced b y n ow . I t m ay b e h eretical, b ut p erhaps a ccurate, t o s ay t hat m uch o f a rchaeology w as r ather s low t o s eize t he p ossibilities . F rom t he 1 960s t here c ould b e n o r eal e xcuse f or n eglecting t he o pportunities, w ith t he p ublication o f b ooks s uch a s t hose b y Martin A itken ( 1961 ) a nd L eo B iek ( 1963 ) a nd t hen t he f irst e dition o f S cience i n Archaeology i tself i n 1 963 . W hat f urther p rogress h as b een m ade i n t he l ast t wo d ecades? I n B ritain we h ave s een c onsiderable a chievements . T he c reation o f t he S cience-Based A rchaeology S ubC ommittee o f t he S cience a nd E ngineering P esearch C ouncil h as a llowed s ome s ignificant f unds t o b e d irected i nto r esearch. U niversity A rchaeology D epartments h ave, t o v arying d egrees, s ought t o a dopt a s cientific s tance; r eflected n ot l east i n my o wn U niversity 's c ommitment t o t eaching A rchaeoloqical S cience a s a n i ntegrated s ubiect . F ield a rchaeology i n t he p rofessional U nits h as t aken o n v arious a spects o f a rchaeological s cience, f or e xample i n c onservation a nd e nvironmental a rchaeology , s upported b y i nstitutions l ike t he A ncient Monuments L aboratory . Much i mportant w ork h as b een c arried o ut i n r esearch l aboratories , s uch a s t hose a t O xford a nd t he B ritish M useum . T he Journal o f A rchaeological S cience n ow c arries r eports o n a ll a spects o f w orldwide a rchaeological s cience . All t hese a re p ositive d evelopments, b ut i t d oes n ot f eel t o m e a s i f t he r evolution h as a rrived t hroughout a rchaeological s cience . T here i s s till t he f eeling i n c omparing S cience i n A rchaeology w ith t he C BA 's r ecent s tatement o n Research Priorities ( Mellars, 1 987) t hat, y es t here h ave b een i mprovements a nd a dvances , b ut t here a re s till t oo m any c ases w here w e a re s aying " Gosh, i sn 't i t e xciting t hat w e k now h ow t o f ind t his o ut!", r ather t han " Look w hat w e h ave f ound o ut - w e n ow u nderstand t his b etter" . A lthough i t i s t rue t hat p ublic e xpenditure i n B ritain h as b een t ightly c ontrolled f or much o f t he p ast t wo d ecades, s o t hat w e h ave n ot h ad a ll t he r esources t hat w e w ould h ave l iked, i t i s s till t he c ase t hat very s ubstantial s ums o f money h ave b een s pent o n a rchaeological s cience, a nd c ertainly m ore t han h ad b een s pent

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p reviously . I n t rying t o a ssess h ow w ell a rchaeological s cience h as d elivered r esults, w e m ust a sk h ow q uestions h ave b een p osed i n t his r esearch , a nd w hat a nswers h ave t hereby b een g enerated . T here a re t wo p roperties o f ag ood q uestion o r r esearch d esign : 1 ) t he p roblem c an b e t ackled b y t he a pproach c hosen 2 ) t he p roblem i s w orth t ackling Aw orthwhile r esearch d esign m ust h ave b oth p roperties . I f t he q uestion p osed c annot b e d ealt w ith b y t he m eans o r t echniques a vailable, t he r esearch e ffort w ill b e aw aste o f t ime, n o m atter h ow i ntrinsically i nteresting t he q uestion . T his i s a n a rea w here t he s cientists c an o ften i ndulge t hemselves b y t aking t he r ole o f t he h ard-headed r ealist , w hen t heir i nnocent a rchaeological c olleagues h ave e xcessi ve e xpectations o f w hat s cientific w izardry c an d eliver . T he i ncidence o f w ork w hich h as f ailed t his t est i s n ot t oo h igh i n a rchaeological s cience , p erhaps b ecause t his w ork d oes n ot m ake i t t o p ublication . I n a nalytical r esearch , f or i nstance , i f am ethod d oes n ot w ork - i t d oes n ot w ork . S tatistics, h owever, p rovide m uch m ore o pportunity f or o bscuring f aulty m ethod ( cf . T homas , 1 978 ). Y et i t i s j ust a s m uch t he c ase t hat , t o b e u seful, s cientific a pplications h ave t o b e m atched t o m eaningful a rchaeological q uestions . A g ood s cientific t echnique w hen a pplied t o a b adly u nderstood a rchaeological s ample d oes h ave t he a dvantage o ver t he o ther k ind o f d ifficulty t hat i t p roduces r esults t hat m ay g et p ublished . W hat i t w ill n ot y ield i s am eaningful a nswer t o t he a rchaeological p roblem . A v ery e fficient a nalysis o f t he f abric o f a p ot m ay b e d one b y i nductively-coupled p lasma s pectroscopy o r n eutron a ctivation . I t w ill t ell u s t he p roportions o f t he e lements t hat m ake u p t he p ot . T his i n i tself i s n ot " big n ews", a s e verything i s m ade o f s omething . I f w e w ant t o g o b eyond s aying " This p ot i s m ade o f s omething ! " , w e h ave t o c ompare t he r esults w ith t hose f rom o ther a nalyses . T hen t he u sefulness o f t he c omparison d epends o n a rchaeological c riteria . T o c ompare R oman p ottery f rom B ritain w ith p ottery f rom T eotihuacan i n M exico a nd s how t hat t hey a re a nalytically d ifferent w ould n ot b e m eaningful . S uch a n o utlandish r esearch p rogramme w ould p robably n ot a ttract f inancial s upport, b ut s ome p rojects t hat h ave b een s upported h ave s hared t he s ame f undamental f laws i n t heir a rchaeological r easoning , i f o n a l ess o bvious s cale . T he c ore o f my a rgument t herefore i s t hat t he e ssential t est o f v alidity i n a rchaeological s cience i s a rchaeological: h ow s uccessfully d oes i t c ontribute t o o ur u nderstanding o f t he a rchaeological r ecord a nd t he h uman p ast? R adiocarbon d ating i s e legant a nd i nteresting s cientifically , b ut i ts c hief i mportance i n a rchaeological s cience l ies i n i ts a pplication - a nd h ow a ccurately i t c an b e u sed t o d efine p rehistoric c hronologies . Much r adiocarbon r esearch n ow c oncerns a spects o f c alibration a nd t he u se o f s mall s amples , b oth r esulting i n g reater u sefulness o f t he m ethod t o a rchaeology . A nswers I n o ther a reas t he c loseness o f t he i ntegration b etween t he a rchaeological p roblem a nd t he s cientific m ethod v aries . P robably t he

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c learest a dvances h ave c ome i n t he s tudy o f a rchaeological a nimal b ones a nd s eeds . M odern e xcavation n ow t reats t he r ecovery o f b ones a nd s eeds a s r outine , a nd w e h ave c ome t o e xpect t hat a ny r eport s hould h ave i ts e nvironmental s ection , j ust a s i t m ight h ave a p ottery r eport . T here i s n ow a n e ver-increasing d atabase o f t his m aterial o n w hich s ound i nterpretations o f p ast h uman a ctivities c an b e b ased , e ven i f a s y et t here a re f ew s yntheses w hich m ake f ull u se o f i t ( cf K ing , 1 984 ). T his p rogress h as l argely b een g enerated t hrough t he a cceptance b y p ublic a gencies l ike t he D epartment o f t he E nvironment/English H eritage o f t he i mportance o f t his i nformation , a nd t heir w illingness t o f und i t a s a r outine a ctivity . I t i s t his a ttitude w hich h as a llowed t he d evelopment o f e xcellent g roups i n t his f ield, g roups l ike t he E nvironmental A rchaeology U nit a t Y ork . G eophysical s urvey h as a lso b ecome r elatively s uccessful i n m atching a rchaeology a nd s cience . R ecent d evelopments i n p rocessing t he d ata f rom r esistivity a nd m agnetic s urveys h ave p roduced g reat i mprovements i n t he s peed o f i nterpretation o f t he r esults a nd t heir i ntelligibility . I t r emains t he c ase h owever t hat m any a rchaeologists a ssume t hat g eophysical s urvey a lone w ill a nswer a ny q uestion a bout w hat l ies u nderneath t he g round . I t i s m y o wn e xperience t hat s atisfactory i nterpretations o f a ll b ut t he s implest s urveys o nly c ome f rom c lose d iscussion a nd a rgument b etween t he s urveyor a nd m yself a s a rchaeologist . P erhaps a rchaeologists h ave b een k een t o u se g eophysical s urvey b ecause i t o ffers i nformation o n s ubjects c lose t o o ur h eart w here w e s hould d ig o ur h oles a nd w hat l ies b eyond w here w e c an d ig . W hen w e d ig i n ac emetery , i t m ight b e t hought t hat i t w ould b e o bvious t hat o ne o f t he m ost s ignificant s ets o f e vidence s hould b e t he h uman r emains t hemselves . S adly , w hat m ay b e o bvious i s n ot a lways a cted u pon . T here h as b een l ittle a ttempt t o i ntegrate s ubstantial s keletal r eports i nto a f ull d iscussion o f t he c emetery p opulations , s ince p olicy i s u sually t o p rovide a s imple d escription o f t he b ones . W hat i s e ven m ore s urprising i s t he l ack o f c omparability b etween s keletal r eports . T here i s a r emarkable l ack o f c onsistency i n t he f rameworks o f d escription u sed b y d ifferent s pecialists , a nd t his m akes i t v ery d ifficult t o d raw d ifferent r eports t ogether i nto s ome s ort o f s ynthesis . Ia m c urrently a m ember o f t he C BA 's W orking P arty o n t he S cientific S tudy o f H uman R emains , w hich i s t rying t o e stablish a greed m inimum s tandards f or s keletal r eports . I t i s n ot a ny e asy t ask , b ut w e a re o ptimistic t hat w e c an l ay a c ommon a nd c omparable f ramework f or t he f uture . B eyond t he l evel o f t he b asic d escriptive r eport , t here i s s till c oncern a bout t he a pplication o f s pecialised r esearch a pproaches . F or e xample, t here a re s till t hose w ho w ould l ike t o l ook a t b lood g roups i n as et o f f ive o r s ix s keletons , w hich m akes l ittle a rchaeological o r s cientific s ense. Other a pproaches, s uch a s t he u se o f c alcium/strontium l evels i n b one f or p alaeodietary r esearch , n eed c areful t hought . T here a re c learly s till s ome d ifficulties w ith t his p articular t echnique a nd i t r emains , a t b est , ar ather c rude i ndicator . T here c an b e l ittle u seful r esult e xpected f rom s eeking v ariations w ithin a s ingle A nglo-Saxon v illage c emetery p opulation , a s w e o nce d id a t B radford f or a n u ndergraduate t hesis . A t t hat l evel i t w as a u seful t echnical e xercise , b ut t he c hoice o f m aterial o n w hich t o a pply t his t echnique i s c rucial. I t m ay b e t hat c lear d istinctions c an o nly b e

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a chieved b etween p opulations t hat a re s o f ar a part i n t ime o r s pace t hat a ny r esults a re a rchaeologically m eaningless . T wo p oints a re s tarkly i llustrated i n t he f ield o f h uman r emains - 1 ) t he p aramount n eed f or r esearch t o b e c onducted i n a c ollaborative t eam c ontainina a rchaeological a nd s cientific s pecialists w orking t ogether a nd 2 ) t he f alseness o f t he d ivision b etween s ervice r eporting a nd r esearch . F or m e, s ome o f t he m ost d isappointing w ork i n a rchaeoloaical s cience h as c ome i n t he f ield o f a nalysis . H ere, a bove a ll, i t i s p ossible t o a rgue t hat y ou h ave w orthwhile r esults s imply b ecause y ou h ave s hown t hat a n a rtefact w as m ade o f s omething . L arge a mounts o f r esources a nd t ime h ave b een s pent i n e laborate p hysico-chemical a nalysis o f p ottery a nd o ther m aterials, o ften w ithout a ny r eal q uestions b eing a sked a bout w hether t he r esults a chieved w ill b e o f a ny v alue . T he a pproach i s t oo o ften a r ather o utdated a ntiquarianism , d escribing t he c omposition o f s omething a nd g oing n o f urther t owards i mproved u nderstanding . T he l imit o n t he n umber o f s amples t hat c an b e e xamined i n a s ingle r esearch p roject m eans t hat t he s election o f t he s amples t o b e a nalysed h as t o b e m ade i n t he m ost s ensitive w ay , i n o rder t o p rovide t he m aximum p ossible u seful i nformation . T o t ackle a v ery l arge a ncient p ottery s ystem b y a nalysing s amples f rom a h andful o f k ilns , w hen a t l east h undreds o f k ilns m ust h ave e xisted o riginally , i s o ver o ptimistic . B ecause o f t he l arge n umber o f k iln s ites , i t i s i mpossible t o u se s uch r esults w ith a ny c onfidence w hen e xamining m aterial a t c onsumption s ites . T he v alue o f d efining c haracteristics o f p roduction c entres i s n ot j ust t o b e a ble t o s ay t hat t he p ottery f rom t his k iln g roup i s d ifferent f rom t he p ottery f rom t hat o ne , b ut t o b e a ble t o d escribe a ccurately d istribution n etworks, a nd t hereby t o u nderstand s omething o f e xchange s ystems . T he r eally l arge p roblems n eed t o h ave a t hroughput o f s amples b eyond e ven w hat I CPS c an c urrently o ffer . I n o ur a pproaches t o r ecent p rojects i n B radford w e h ave t ried h ard t o m atch p ractical a rchaeological p roblems w ith a ppropriate a nalytical p rocedures . A gain t he n eed i s f or t he c losest c o-operation b etween s pecialists , p articularly w hen t he r esearch d esign i s b eing p lanned . M oving f orward M any o f t he p roblems I h ave t ried t o h ighlight d erive f rom t he s plintered s tructure o f a rchaeological s cience i n B ritain, a nd t herefore r elate d irectly t o i ssues o f o rganisation a nd f inance . T he s ame i ssues a re f requently r aised b y c ontributors t o t he C BA 's R esearch P riorities i n A rchaeological S cience v olume ( Mellars , 1 987 ). B ehind i t a ll l ies h ow w e o rganise k nowledge . T he w ord S CIENCE h as c ome t o t ake o n a v ery n arrow m eaning, a nd i n B ritish p ublic o rganisations i t e xcludes c ategories o f k nowledge c lassed a s h umanities . E ven t he w idely-accepted t erm S ocial S cience h as f allen f rom f avour a mongst p oliticians a nd b ureaucrats , a nd t he S ocial S cience R esearch C ouncil h as b een r enamed t he E conomic a nd S ocial R esearch C ouncil. T he d istinction m ay s eem p etty t o t hose m ore c oncerned w ith t rying t o d o a cademic r esearch, b ut i t h as r eal i mplications f or a s ubject l ike a rchaeology/archaeological s cience w hich h as t o s pan b ureaucratically i mposed b oundaries . M y w hole p oint i s t hat g ood a rchaeological s cience r esearch n eeds t o b e i ntegrated , p robably w ith a t eam o f c ollaborators , s o t hat i t i s b oth g ood s cience a nd g ood a rchaeology , b ut t his m eans t hat i t f its u ncomfortably i nto t he s trictures o f t he S cience a nd

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E ngineering R esearch C ouncil . E xplicitly , i t e merges i n t he q uestion o f w hether t he a pplication o f am ore o r l ess w ell-understood t echnique t o a n a rchaeologically w orthwhile p roblem c onstitutes a rchaeological s cience r esearch o r n ot . I f o ne 's c oncern i s t he p ursuit o f k nowledge, t he s emantics m ay n ot m atter t oo m uch ; t hey m atter a l ot i f y ou a re c oncerned w ith t he b ureaucracies o f f unding a gencies . C learly a ll f unding a gencies h ave t o h ave s ome k ind o f f ramework t o o perate i n . W hat h as t o b e s aid a bout a rchaeology i s t hat t he f unding s tructure c omprising t he S ERC, t he B ritish A cademy a nd E nglish H eritage a nd i ts s iblings e lsewhere i n t he U nited K ingdom d oes n ot p rovide a c omprehensive s upport f or r esearch . N one o f t he p ublic a gencies c onsistently s upports i ntegrated a rchaeological r esearch i n a m anner t hat c an c over t he c osts o f m odern s cientific m ethods . T hat i s w idely r ecognised , a nd i s n ow b eing e xamined . W e m ust r eserve j udgement o n t he s olutions o ffered u ntil t hey a re m ade p ublic . Y et , a t l east a s i mportant a s t he o rganisational f ramework i n w hich w e o perate, i s t he a ttitude o f t he p eople w ho a re d oing t he w ork . C oo rdination a nd c omparability m ust b e t he b y-words . A s d iscussed b y s everal c ontributors t o R esearch P riorities , t here i s ac lear n eed f or t he e stablishment o f c ommon d atabases f or s pecialist g roups, t he e xchange o f s tandards b etween l aboratories , a nd a r equirement t o w ork t o s tandard c omparable r ecording s chemes . S uch m easures o pen t he w ay t o s ynthesis a nd i nterpretation o f t he b asic d ata . F urther p rogress w ill b e a chieved i f g roups o f s pecialists c an l earn t o c ollaborate . T he n umbers o f p eople i nvolved a re s o s mall t hat i t i s aw aste o f e ffort t o b e t oo c ompetitive w ith e ach o ther . T he S BAC c ould t ake p ositive i nitiatives t o e ncourage g roups o f s pecialists t o a gree c ommon c ollaborative p rogrammes . R elatively s mall s ums a llocated t o s upport s pecified p rogrammes o f w orkshops a nd w orking g roups c ould r esult i n g roups s etting t heir o wn e xplicit t argets over a p lanning p eriod . I t m ust s urely b e b etter f or a g roup o f s pecialists t o s et t heir o wn a genda, r ather t han h ave i t i mposed b y t he S BAC w ith i ts i nevitably r estricted e xpertise . S uch a n a genda s hould c onform t o t he c riteria o f g ood i ntegrated r esearch d esign t hat w ere o utlined a bove. F inally, i f s cientific a nd a rchaeological r equirements i n a rchaeological s cience a re mutually d ependent, t heir s uccessful i ntegration m ust i n t urn d epend o n t he p eople w orking a nd t heir b ackground a nd t raining . W e n eed c ontributions f rom p eople w ith a s pectrum o f q ualifications, f rom t he a rchaeologically-aware p ure s cientist t hrough t o t he s cientifically-aware p ure a rchaeologist, t hrough a w ide r ange o f c ombinations . O ur a pproach t o t eaching i n B radford a ims t o s atisfy p art o f t hat n eed, s panning t he i nterfaces b etween a pplied s cience a nd a pplied a rchaeology . S o o ften w e c an s ee m ethods w here t he b asic t echnique i s s cientifically w ell-established . M uch f uture p rogress w ill d epend o n w ork d one b y t hose p roperly e quipped t o m atch t he t echniques t o t he a rchaeological p roblems . H ow s uccessful w e c an b e a t t hat t ask w ill d etermine t he s uccess o f a rchaeological s cience i n e xpanding o ur u nderstanding o f t he h uman p ast .

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R EFERENCES A itken M .J. B iek L .

( 1961)

( 1963 )

P hysics a nd A rchaeology

A rchaeology a nd t he M icroscope

B rothwell D . &H iggs E . ( 1969) p rogress a nd r esearch ( 2nd e d.) D eetz J . r evisited

S cience i n A rchaeology . A s urvey o f

( 1988) H istory a nd a rchaeological t heory : Walter T aylor Amer.Antiquity 5 3 ( 1 ) 1 3-22

Evans J . ( 19 8 7 ) The f irst half-century B ull.Instit.Archaeol.London 2 4 1 -26

- and

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K ing A .C . ( 1984 ) A nimal b ones a nd t he d ietary i dentity o f m ilitary a nd c ivilian g roups i n R oman B ritain , G ermany a nd G aul . I n T .F .C .Blagg &A .C .King ( eds ) Military a nd C ivilian i n Roman B ritain BAR 1 36 1 87-217 Mellars P .(ed ) C BA T homas D .H . A mer.Antiquity

( 1987)

R esearch P riorities i n A rchaeological S cience

The a wful t ruth 4 3 ( 2 ) 2 31-44

a bout

7

s tatistics

i n

a rchaeology

T HE STUDY O F ANCIENT C ERAMIC T ECHNOLOGIES: P AST A CHIEVEMENTS A ND FU TURE P ROSPEC T 'S M .S. T ite B ritish M useum R esearch L aboratory , L ondon l e r1B 3 DG

T he c ontribution o f s cientific e xamination t o t he u nderstanding o f a ncient c eramic t echnologies c onsists o f a ttempting t o a nswer t wo b asic q uestions . T he f irst i s " how w as t he p ottery m ade?" a nd i nvolves t he i nvestigation o f t he r aw m aterials a nd t he p roduction m ethods u sed . T he s econd q uestion i s " why w ere p articular r aw m aterials a nd p roduction m ethods u sed?" T his i nvolves l ooking a t b oth t he p roperties o f t he r aw m aterials a nd f inished p roducts, a nd t hus t he p ossible t echnological f actors t hat m ight h ave i nfluenced c hoice, a s w ell a s c onsidering t he o verall c ontext o f p ottery p roduction . T hese t wo q uestions a re, o f c ourse, i n a ddition t o t he q uestions: " when w as t he p ottery m ade?" w hich, i n t he c ontext o f s cientific m ethods, w ould i nvolve t hermoluminescence d ating a nd " where w as t he p ottery m ade?" w hich w ould i nvolve i ts c haracterisation b y t hin s ection p etrology o r t race e lement a nalysis . I n t his r eview p aper I i ntend f irst t o l ook v ery b riefly a t s ome o f t he d evelopments i n t he m ethodology u sed t o i nvestigate h ow c eramics w ere m ade . S econd , Iw ill c onsider s ome o f t he a ttempts t hat h ave b een m ade t o a nswer t he q uestion w hy p articular p roduction m ethods w ere u sed . T hird, I w ill d iscuss t he f uture r ole o f s cientific m ethods i n t he s tudy o f a ncient c eramic t echnologies . I n c onsidering t hese v arious t opics I w ill b e c oncerned m ainly w ith c lay-based e arthenware c eramics w hich a re t he p rimary i nterest o f E uropean a rchaeologists . H ow w ere c eramics m ade? I n o rder t o e stablish h ow a ncient c eramics w ere m ade i t i s n ecessary t o i nvestigate ( 1 ) w hat m aterials w ere u sed ; ( 2 ) h ow t hese m aterials w ere p repared ( e .g . w hat r efining w as d one a nd w hat t emper w as a dded); ( 3 ) h ow t he p ots w ere f ormed ( e .g . f rom c oils o r s labs o r b y w heel t hrowing ); ( 4 ) h ow t hey w ere d ecorated ( e .g . b y b urnishing, t he a pplication o f as lip o r p ainted u sing p igments ); ( 5 ) h ow w ere t hey f ired ( e .g . w hat t emperatures a nd a tmospheres w ere u sed ). I nherent i n s uch i nvestigations i s t he i ntention o f a lso u nderstanding h ow s pecific v isual e ffects , p articularly t hose a ssociated w ith t he d ecoration , w ere a chieved. T he m ajority o f t he s cientific t echniques e mployed i n a nswerina t hese q uestions a re n ow f airly w ell e stablished a nd h ave b een e xtensively u sed t o s tudy a ncient c eramics . S uch a n i nvestigation s tarts w ith c areful v isual e xamination, m oves t hrough o ptical m icroscopy a nd r adiography t o s canning e lectron m icroscopy ( SEM) t ogether w ith v arious a nalytical t echniques s uch a s X -ray f luorescence, X -ray d iffraction a nd m ossbauer s pectrometry .

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T he p rincipal n ew d evelopments i n m ethodology d uring t he p ast d ecade h ave b een t he i ncreasing u se o f x ero-radiography , s canning e lectron m icroscopy a nd M ossbauer s pectrometry , e ach o f w hich w ill b e c onsidered b riefly b elow . R adiography h as a lways b een u sed t o h elp e stablish h ow p ottery w as f ormed . H owever, t he m ore r ecent a pplication o f x ero-radiography h as b een o f p articular v alue i n t hat w ith t his m ethod t he i mages o f a ny j oins , e dges o r d iscontinuities w ithin a c eramic b ody a re e nhanced ( Chapman e t a l, t his v olume ; F oster, 1 985; G lanzman a nd F leming, 1 986 ). E xamples o f x ero-radiographs a re s hown i n f igure 1 . T he x ero-radiograph o f a M edieval c ooking p ot ( figure l a ) s hows , i n t he u pper p art , t he o blique a lignment o f p ores a nd i nclusions w hich i ndicate w heel t hrowing . T he i rregular t hickness a nd m ore r andom a lignment o f p ores a nd i nclusions i n t he l ower p art s uggests t hat t he b ase w as s ubsequently p ushed o ut b y h and . A gain, i n t he c ase o f a M edieval j ug ( figure l b ), o blique a lignment o f p ores a nd i nclusions i ndicates w heel t hrowing . H owever, m ore i mportantly , i t i s p ossible t o s ee t hat t he h andles w ere c onstructed b y p ushing t hem i nto t he b ody w ith t he i nside b eing s moothed a t t he t op o nly . I n a ddition, t he s eparate s upport a dded t o s trengthen t he h andle i s c learly v isible . S canning e lectron m icroscope e xamination o f b oth f ractured a nd p olished s ections o f c eramics h as b een i ncreasingly u sed i n t he i nvestigation o f c eramic t echnology , ( T ite e t a l, 1 982b ; F reestone a nd M iddleton, 1 987 ). T his t echnique p rovides i nformation o n t he m icrostructure o f t he p ottery a nd, i n c onjunction w ith e nergy d ispersive x -ray s pectrometry , o n t he c hemical c omposition o f t he v arious p hases . I t h as b een u sed i n t he d etermination o f p ottery f iring t emperatures ( Maniatis a nd T ite, 1 981 ) a nd h as a lso b een p articularly v aluable i n t he s tudy o f s urface d ecoration ( rite e t a l, 1 982a ). A r ecent a pplication h as b een t o ag roup o f e arly I ron A ge c eramics; c eramics w ith a d istinctive b right r ed a nd o ften g lossy s urface w hich h ave b een r eferred t o a s h aematite-coated w are ( Middleton, 1 987 ). T he S EM e xamination s howed t hat , i n a ddition t o t he a pplication o f c rushed h aematite , f erruginous c lay s lip c oatings a nd b urnishing w ere a lso u sed t o t reat t he s urface ( figure 2 ) . H ence, w hilst c eramics o f t his t ype t end t o b e g rouped t ogether b ecause o f t heir s imilar s urface a ppearance, t he t erm h aematite-coated w are i s r eally o nly a ppropriate f or s ome o f t he c eramics i n t his g roup . Mossbauer s pectrometry h as b een e xtensively u sed i n t he i nvestigation o f c eramic t echnology d uring t he p ast d ecade ( Maniatis e t a l, 1 982 ; W agner e t a l, 1 986 ). T his t echnique p rovides i nformation o n t he s tate o f t he i ron ( i .e . w hether i t i s i n t he f errous o r f erric f orms ; w hether i t i s p resent a s i ron o xides, i ron s ilicates o r i ncorporated i n t he c lay m inerals ) a nd t hus h elps i n t he d etermination o f t he f iring a tmosphere a nd f iring t emperature. I n o rder t o d istinguish b etween f iring i n o xidising a nd r educing a tmospheres t he r elative p roportions o f f erric a nd f errous i ron a re u sed, a nd i t i s a lso p ossible t o d etermine t he f iring t emperature f or p ottery b y r efiring s amples, r e-measuring t heir Mossbauer s pectra a nd t hus e stablishing t he r efiring t emperature a t w hich a c hange i n t he Mossbauer p arameters o ccurs .

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H owever, p roblems a ssociated w ith t he c onversion f rom f errous t o f erric i ron , a nd w ith t he w eathering t hat h as o ccurred d uring b urial, c an s everely l imit t he p recision o f t his m ethod f or d etermining f iring t emperatures . I n s u mary , t herefore , w hen u sed i n i solation M ossbauer s pectrometry i s o f o nly l imited v alue f or t he s tudy o f a ncient c eramic t echnologies , a nd i ts o verall i mportance h as b een s omewhat o verrated d uring t he p ast d ecade . H owever, w hen u sed i n c onjunction w ith o ther m ethods , M ossbauer s pectrometry c an m ake a u seful c ontribution . W hy w ere p articular p roduction m ethods u sed? I n c onsidering w hy p articular p roduction m ethods w ere u sed t o m ake c eramics , a s w ell a s t he r elated a uestion o f w hy c hanges i n p roduction m ethods h ave o ccurred, t here a re i n s ome c ases c lear t echnological r easons f or t hese c hoices , a nd s ome e xamples o f t hese a re g iven b elow . F irst , t he p roperties o f t he a vailable r aw m aterials c an i nfluence t he p roduction m ethod u sed . F or e xample, R ye ( 1976 ) h as o bserved t hat p resent-day M elanesian p otters u se a s hell t empered c lay t o m ake t heir p ottery a nd t hat t his i s w etted w ith s ea ( salt ) w ater . S imilarly , t he a ddition o f s alt h as b een i nferred i n t he c ase o f s ome N ear E astern p ottery ( Matson, 1 971 ) a nd N orth A merican I ndian p ottery ( Stimmell e t a l, 1 982 ) m ade f rom c alcareous o r s hell t empered c lays , a nd t his u se o f s alt m ay h ave a p ractical e xplanation i n t he c ase o f s hell t empered m aterial. I f s hell i s h eated a bove a bout 7 50 ° C i t d issociates t o l ime ( CaO ). T he l ime f airly r apidly r ehydrates t o c alcium h ydroxide w hich o ccupies a l arger v olume t han t he l ime a nd t hus c auses t he d isintegration o f t he p ottery . H owever, b y t he p reparation o f a s eries o f e xperimental b riquettes, R ye s howed t hat t he a ddition o f s ea w ater e ffectively p revents t his d isintegration , a nd t his m ay w ell b e t he r eason f or i ts u se . H owever, t his w as a n e mpirical o bservation a nd t he m echanism b y w hich t he r eaction b etween t he c alcium c arbonate a nd t he s odium c hloride p revents s ubsequent d isintegration i s n ot e asy t o d etermine . I t i s p ossible t hat l arger p ores a re c reated w ithin t he o riginal c alcium c arbonate, t hus p roviding s pace t o a ccommodate t he e xpansion o ccurring d uring r ehydration w ithout d isrupting t he b ody ( Sti l well e t a l, 1 982 ). S imilarly , Vandiver ( 1988) h as s hown t hat p ottery f rom 6 th m illennium B C I ran w as c onstructed f rom s labs o f c lay t empered w ith c haff, w hereas p ottery f rom 4 th m illennium B C N orthern C hina w as c onstructed f rom c oils o f c lay w ith s ubsequent t amping . S he h as a rgued t hat t he r eason f or u sing t hese d ifferent f orming m ethods i s a ssociated w ith t he d ifferent t ypes o f c lay a vailable i n t he t wo re gions . I n I ran a m ontmorillonitic c lay w ith v ery f ine c lay p articles a nd a v ery h igh d rying s hrinkage w as u sed . T herefore c haff m ight h ave b een a dded t o t his c lay t o i ncrease i ts s trength a nd d ecrease i ts d rying s hrinkage . H owever, t he l inear n ature o f t he c haff m akes c oil c onstruction d ifficult a nd s o s labs w ere u sed i nstead . I n N orth C hina a k aolinitic c lay w ith c oarse c lay p articles a nd a l ower d rying s hrinkage w as u sed . T his c lay h as o nly a s mall r ange o f w ater c ontent w ith w hich i t c an b e r eadily w orked ( i .e . i t i s a s hort c lay ). T herefore , t he p ottery m ust b e f ormed f rom s mall c lay e lements, s o t hat t he w ater c ontent d oes n ot c hange s ignificantly d uring t he a ddition o f e ach e lement, a nd t hus

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c oils w ere u sed i nstead o f s labs . I n a ddition t o t he p roperties o f t he r aw m aterials, t he p hysical p roperties o f t he f inished p ottery i tself ( e .a . p ermeability , s trength, t hermal s hock r esistance ) c an i nfluence t he p roduction m ethods u sed . D uring t he p ast f ew y ears t here h as b een m ore i nterest i n t his a spect o f c eramic t echnology ( e .g . B raun, 1 983; B ronitsky, 1 986) i ncluding t he p ioneering w ork o f S teponaitis ( 1984 ) w orking o n N orth A merican I ndian p ottery . S teponaitis f ound t hat t he c ooking p ots c ontained a bundant c oarse s hell t emper, w hereas s erving a nd s torage p ots c ontained s parse f ine s hell t emper. H e t hen s howed t hat a s ar esult o f af iner t emper t he s erving a nd s torage p ots h ad h igher t ensile s trength ( figure 3 a ) a nd t hus g reater r esistance t o b reakage. H e f urther a rgued t hat t his r esistance t o b reakage i s a n ecessary p roperty o f s uch p ots , a nd h ence t hat f ine t emper w as d eliberately a dded t o t hese p ots f or t his r eason . S teponaitis a lso s howed t hat , a s a r esult o f t heir c oarse s hell t emper, t he c ooking p ots t ended t o h ave a g reater r esistance t o t hermal s hock a t l east i f m easured i n t erms o f t he r esistance t o l oss o f s trength o nce c racking h as b een i nitiated ( figure 3 b ) - a lthough t he c orrelation i n t his c ase w as n ot a ltogether c onvincing . H e a gain a rgued t hat t his i s an ecessary p roperty o f c ooking p ots w hich a re s ubjected t o r apid c hanges i n t emperature, a nd h ence a c oarse t emper w as d eliberately a dded t o t hese p ots . F inally , h e s howed t hat t he u se o f s hell t emper f or c ooking p ots r epresented a f inal s tage i n t heir d evelopment a nd s uggested t hat t he o bserved c hanges i n t emper f rom p lant f ibre t hrough s and a nd g rog t o c oarse s hell w ere a ssociated w ith t he n eed o r d esire t o a chieve i mprove t hermal s hock r esistance . I nstead o f t he d irect m easurement o f t he p hysical p roperties o f c eramics , a n a lternative a pproach i s t o a nalyse t hose c haracteristics o f c eramics s uch a s v essel s hape, w all t hickness, a nd t emper c oncentration a nd t ype w hich d etermine t he p hysical p roperties a nd h ence p erformance i n u se . T his l atter a pproach h as a n umber o f d efinite a dvantages s ince d irect m easurement n ormally o nly p rovides d ata o n r esidual p erformance a fter t he c eramic h as s uffered f ailure i n u se a nd p ostdepositional c hange . F or e xample, B raun ( 1983 ) h as s hown t hat, d uring t he p eriod 6 00 B C t o 9 00 A D, t he w all t hickness o f W oodland p eriod p ottery f rom I llinois d ecreased p rogressively . H e h as c onvincingly a rgued t hat t his d ecrease i n w all t hickness w as m ade i n o rder t o a chieve i ncreased h eat c onduction a nd i ncreased t hermal s hock r esistance . T he r eduction i n t ensile s trength r esulting f rom t he d ecreased w all t hickness w as p ossibly p artly c ompensated f or b y a d ecrease i n t he q uantity a nd p article s ize o f t he t emper . F urther, h e h as s uggested t hat t his c hange i n p erformance c haracteristics w hich a llowed t he vessels t o b e u sed u nder more t hermally s tressful c onditions, a rose a s ar esult o f c hanges i n s ubsistence a nd d ietary p ractice i nvolving i ncreasing c onsumption o f s tarchy s eeds w hich n eeded t o b e s immered o r b oiled . S uch p erformance-based e xplanations f or d ifferences a nd c hanges i n p roduction m ethod a nd , i n p articular, t he i mportance o f s hell t emper t o i mprove t hermal s hock r esistance i n c ooking p ots , h ave b een q uestioned b y W oods ( 1986 ). S he s howed t hat i n B ritain f rom t he N eolithic t hrough t o t he M edieval p eriod t here i s l ittle e vidence f or t he d eliberate u se

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o f as pecific i nclusion t ype f or c ooking p ots , a nd t hat q uartz s and w as p robably a m ore c ommon t emper t han s hell o r l imestone . S he a rgued i nstead t hat t he c rucial f actor i n s o f ar a s c ooking p ots a re c oncerned i s t he c oarseness a nd o penness o f t he f abric w hich d etermines i ts a bility t o a ccommodate t he s tresses a ssociated w ith e xpansion a nd c ontraction . S he f urther e mphasised t he d ancer o f b ecoming o bsessed w ith t echnological f actors s uch a s t hermal s hock r esistance i n s tudying a ncient c eramics . H ence , a lthough t echnological a spects r elating t o t he p roperties o f t he r aw m aterials a nd f inished p roducts p rovide s ome e xplanation f or t he u se o f p articular p roduction m ethods , t hese a re c learly o nly p art o f t he a nswer t o t he q uestion w hy . T his i s e specially t rue i n t he c ase o f c lay-based e arthenwares, f or w hich t he r epertoire o f b asic t echniques i s f airly l imited a nd h as b een m ore-or-less u nchanged s ince t he 4 th m illennium R C . T herefore , t o f ully a nswer t he q uestion " why p articular p roduction m ethods a re u sed?" a nd, a t t he s ame t ime, t o f ully r ealise t he p otential o f p ottery f or y ielding i nformation a bout t he p eople w ho m ade a nd u sed i t , i t i s n ecessary t o c onsider a ll s tages i n t he p ottery c ycle f rom s election o f t he r aw m aterial t hrough t he p roduction o f t he p ottery t o t he d istribution , u se a nd d iscard o f t he f inished p roduct . T hese s tages i n t he p ottery c ycle n eed t o b e c onsidered t ogether w ith t he a ssociated n atural, c ultural, s ocial a nd e conomic e nvironments . T hus t he i nvestigation o f p ottery p roduction m ethods s hould b e s een a s a n e xample o f t he c ontextual a pproach t o a rchaeological i nterpretation a dvocated b y H odder ( 1986 ). U sing t his a pproach , p ottery p roduction m ethods a re c onsidered w ithin t heir o verall c ontext o r e nvironment , r elevant a spects o f w hich i nclude n atural r esources , o rganisation o f p roduction, p ottery f unctions , p ottery s tyle a nd d istribution o f f inished p roduct a s w ell a s r elated t echnologies . T hus t he p roduction m ethods a re i nterpreted b y a sking q uestions a bout h ow d ifferences i n t he m ethods u sed i n d ifferent r egions , a t d ifferent p eriods a nd f or d ifferent p ottery t ypes r elate t o t hose c ontextual a spects . A mong t he q uestions t hat n eed t o b e a sked f or t he d ifferent r egions, p eriods a nd p ottery t ypes , a s a ppropriate , a re t he f ollowing : W hat n atural r esources , i ncluding w ater a nd f uel a s w ell a s c lay a nd t emper, w ere a vailable t o t he p otter? H ow w as t he p ottery p roduction o rganised ; u sing t he c ategories d efined b y P eacock ( 1981 ), w as p roduction b ased o n a h ousehold , w orkshop o r m anufactory ; t o w hat e xtent w as t here d ivision o f l abour a nd s pecialisation ; w hat w as t he s ocial s tatus o f t he p otter? W as t he p ottery u sed f or c ooking , f or s torage , f or s erving f ood o r f or n on-utilitarian r itual p urposes ; h ow d id t he s ubsistence p attern i nfluence t he r ange o f f unctional t ypes; w hat c ontainers , o ther t han p ottery , w ere u sed? W hat w as t he s tyle o f t he p ottery i n t erms d ecoration a nd h ow d id t his r elate t o f unction ; l inks c an b e i nferred f rom t he s tyle?

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o f s hape a nd w hat c ultural

F or w hom w as t he p ottery p roduced; w as i t p roduced f or h ousehold u se o r w as i t f or e xchange o r t rade e ither l ocally o r o ver l arge d istances ; t o w hat e xtent w as p ottery i mported f rom o utside t he r egion u nder c onsideration? Were t here a ny l inks b etween p ottery p roduction a nd o ther t echnologies; w hat i tems, o ther t han p ottery , w ere m ade f rom c lay? T hus t echnological s tudies n eed t o f orm p art o f af ully i ntegrated i nvestigation o f a s pecific g roup o f pottery i nvolving a multidisciplinary a pproach ( i.e. a rchaeological, g eological, t echnological, e tc) a nd s upplemented where appropriate b y e thnoarchaeological s tudies. I n t his w ay a r ich n etwork o f r elationships i s e stablished w hich, i n a ddition t o a nswering t he q uestion o f w hy a p articular p ottery p roduction m ethod w as u sed, c ontributes t o t he o verall u nderstanding o f t he r elationship b etween s ociety a nd m aterial c ulture a nd o f t he c auses o f c hange . A s w ith m ost a spects o f c eramic s tudies , A nna S hepard ( 1956 ) i n t he U SA i n t he 1 950s w as o ne o f t he f irst p eople t o a rgue f or a f ully i ntegrated a pproach t o c eramic s tudies, a nd a ctive a nd i nnovative s upport f or t his i ntegrated a pproach s ubsequently c ame f rom F red M atson ( 1965), a lso i n t he U SA, w ho i ntroduced t he c oncept o f " ceramic e cology" . C urrent p roponents o f t his a pproach i nclude P rudence R ice ( 1985 ), w ho h as w orked o n North American I ndian a nd Mayan c eramics, a gain i n t he U SA . I n E urope, S ander v an d er L eeuw ( 1976) h as b een s imilarly a ctive w ith i nterests s panning p rehistoric t o m edieval c eramics f rom E urope a nd t he N ear E ast . H owever, h e i s, p erhaps, n ow m ore c oncerned w ith t he t heoretical a nd p hilosophical c oncepts a ssociated w ith t he s tudy o f c eramic t echnologies r ather t han w ith t he i nvestigation o f s pecific g roups o f c eramics . Also, i n b oth t he U SA a nd E urope t here h ave b een s everal r ecent P hD t heses t hat h ave p rovided i ntegrated s tudies o f s pecific g roups o f c eramics i nvolving t heir o verall a rchaeological c ontext a s w ell a s t heir t echnology . H owever, e xcept i n t he c ase o f S hepard a nd M atson , t hese p rojects h ave b een u ndertaken b y p eople s ituated t owards t he a rchaeological e nd o f t he a rchaeometry-archaeology s pectrum . A s a r esult, o n o ccasions t here h as b een a t endency e ither f or t he c onclusions t o b e s omewhat n aive s cientifically o r f or t he f ull i nterpretation n ot t o h ave b een d rawn f rom t he s cientific d ata . C onversely , f or t he s cience-trained a rchaeometrist t o b ecome h is o wn a rchaeological e xpert a nd t ackle h is o wn f ully i ntegrated c eramic p rojects i s e gually f raught w ith d anger . A rchaeology i s a s d ifficult a nd s ubtle a s ubject a s s cience a nd t here i s ar eal r isk o f a n a rchaeometrist r eaching c onclusions w hich a re a rchaeologically n aive . T herefore, e xcept i n t he c ase o f t hat r are p olymath w ho i s c apable o f f ully g rasping t he c omplexities a nd s ubtleties o f b oth s cience a nd a rchaeology , c ollaboration s hould b e t he o rder o f t he d ay . I n t his w ay , t he d epth o f b oth s cientific a nd a rchaeological u nderstanding s uch a s c an o nly b e a chieved t hrough l ong i nvolvement w ith o ne o r o ther s ubject c an b e b rought t o b ear o n a c eramic p roject .

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T he f uture r ole o f s cientific m ethods H aving i ndicated i n t he p revious s ection h ow c eramic t echnology s tudies m ight d evelop i n t he f uture, I n ow w ant t o c onsider w hat m ight b e t he p ossible f uture r oles f or s cience-trained a rchaeometrists e ngaged i n t he s tudy o f a ncient c eramic t echnology . F irst , a nd p erhaps f oremost , h e o r s he s hould c ollaborate w ith a rchaeologists o n i ntegrated c eramic p rojects , s uch c ollaboration b eing i nitiated e ither b y t he a rchaeometrists o r b y t he a rchaeologist . W hen s tudying c eramics t hat a re t echnologically m ore c omplex t han t he c layb ased e arthenware t hat I h ave m ainly b een d iscussing s o f ar, t he s cientific i nput w ill b e m ajor a nd t hus t he i nitiation o f ap roject b y t he a rchaeometrists i s p erhaps m ore p robable . S uch c eramics i nclude t hose w ith q uartz-based b odies r anging f rom E gyptian f aience t hrough I snik q uartz-frit c eramics t o E uropean s oft-paste p orcelain ; a lso h ardp aste p orcelains , b oth C hinese a nd E uropean , a nd t in-glazed e arthenware f rom b oth t he I slamic w orld a nd E urope . T he p reliminary s cientific i nvestigation o f t his o verall f ield i s n ow r easonably w ell a dvanced a nd h as b een s ummarised i n a r ecent b ook b y K ingery a nd V andiver ( 1986) e ntitled " Ceramic M asterpieces" . H owever, t here i s s till c onsiderable s cope f or d etailed s tudies i n c ollaboration w ith t he a ppropriate s pecialist , e ither o f s pecific g roups o f s uch c eramics o r o f t he i ntroduction a nd d evelopment o f s pecific a spects o f t he a ssociated c eramic t echnology . F urther, s ince t he p roduction o f t hese m ore c omplex c eramics i nvolved c onsiderable t echnological c hange, u nlike t he e ssentially s tatic t echnology a ssociated w ith e arthenware p roduction , t here i s s cope f or c ontributing t o u nderstanding t he m echanism f or t echnological c hange . A n e xample o f s uch a n i nvestigation w ould b e t o s tudy t he u se o f t in o xide a s a n o pacifier i n g lazes ( figure 4 ). T he i ntroduction a nd s pread o f t his t echnique a re k now i n g eneral t erms ; i n t hat t in o xide a ppears t o h ave b een f irst u sed i n I raq i n t he 9 th c entury i n r esponse t o t he i mport o f w hite w ares f rom T ang C hina . I t s ubsequently s pread a long N orth A frica, r eaching E _ urope b y t he 1 3th c entury t o b e u sed i n t he p roduction o f S panish l ustreware a nd I talian a rchaic m aiolica . H owever, t he d etails o f t he i ntroduction a nd s pread o f t his t echnique a re n ot y et f ully u nderstood . C onversely , w hen s tudying c lay-based e arthenware t here i s s till s cope f or a s ignificant s cientific i nput . H owever, i n t his c ase, p rojects a re p erhaps m ore l ikely t o b e i nitiated b y t he a rchaeologist . T opics w ithin t his c ategory i nclude t he s tudy o f h aematite a nd o ther c lay-based c oatings ; t he i nvestigation o f t he e ffect o f t he v ariation a nd t reatment o f t he r aw m aterials o n p ottery p roduction p rocesses, i ncluding t he a ddition o f s alt w ater t o c alcareous c lays; a nd t he s tudy o f t he e ffect o f i mpurities o n t he v itrification c haracteristics o f p ottery . S uch t opics a re p erhaps n ow b est t ackled w ithin t he c ontext o f s pecific i ntegrated c eramic p rojects r ather t han a s i solated s cience-based p rojects . S econd, a t t he i nterface o f c eramics a nd m etalluray t here i s t he s tudy o f r efractories ( i .e . c rucibles , t uyeres , f urnace l inings , e tc ) a nd p roduction d ebris ( i.e . s lags, e tc) a ssociated w ith m etal p roduction a nd m etal w orking . H ere, t here i s a gain s cope f or a v ery

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c onsiderable s cientific i nput ( Tite e t a l 1 985; F reestone a nd T ite, 1 986). F irst , t he p hysical p roperties o f t he c eramics, s uch a s r efractoriness, t hermal s hock r esistance a nd s trength, a re o f r eal p ractical i mportance s ince m uch g reater d emands a re m ade o n s uch c eramics t han o n d omestic p ottery . S econd , a nd p erhaps m ore i mportant , t he e xamination o f t his m aterial p rovides i nformation b oth o n t he c harge ( i .e . r aw m aterials ) a nd o n t he o perating c onditions ( i .e . f iring t emperature , t ime a nd a tmosphere ) u sed i n t he a ssociated m etal p roduction p rocess . A n e xample o f s uch a n i nvestigation i s t he w ork u ndertaken o n t he f urnaces u sed i n t he p roduction o f z inc i n I ndia d uring t he 1 5th c entury A D ( Craddock, 1 987 ). T he p roblem w ith t he p roduction o f z inc m etal i s t hat i t v apourises a t a bout 9 00 °C s o t hat i t w ould b e l ost i n a ny n ormal s melting p rocess . T herefore, a s pecial t ype o f f urnace ( figure 5 ) w as u sed i n w hich t he z inc o re, c harcoal a nd f lux w ere h eated t ogether i n r etorts i n t he u pper c hamber . T he z inc v apour t hat f ormed c ondensed i n t he l ower c hamber o f t he f urnace b elow a p erforated f loor . T he e xamination i n t he S EM o f t he d egree o f v itrification a nd v itrification g radients f or t he v arious r efractories u sed p rovided c onfirmation o f , a nd c ontributed t o , t he i nterpretation o f t he p rocess . T hus, i t w as s hown t hat t he r etorts w ere h eated t o a bout 1 200 °C ; t he w alls o f t he u pper c hamber o f t he f urnace r eached a bout 1 200 ° C , w ith t his t emperature b eing m aintained f or s ome 5 h ours, a nd t he u pper s urface o f t he p erforated f loor b etween t he u pper a nd l ower c hambers o f t he f urnace r eached a t emperature i n t he r ange 1 050 - 1 150 ° C . F inally , i t w as s hown t hat t he l ower s urface o f t his f loor r eached o nly 7 50 9 50 °C , t hus c onfirming t hat t he t emperature i n t he l ower c hamber w as l ow e nough f or t he z inc v apour f rom t he r etorts t o c ondense . F inally , t here i s t he p ossibility o f e xtending t he r ange o f s cientific t echniques a pplied t o a ncient c eramics . T he s cope f or t his i s p erhaps s omewhat l imited, a nd i t i s e ssential t hat t he p otential u sefulness o f a ny n ew t echnique i s c arefully a ssessed b efore l arge r esources a re d evoted t o i ts d evelopment . H owever, i t w ould c ertainly b e w orthwhile t o e xplore f urther t he p otential o f t ransmission e lectron m icroscopy ( TEM ) f or t he s tudy o f a ncient c eramics . T his t echnique, w ith i ts i ncreased r esolution a nd c apacity f or c rystallographic i dentification, c an s ignificantly e xtend t he d ata o n c eramic m icrostructure b eyond t hat p ossible w ith S EM . H ence , m ore i nformation c an b e o btained o n t he n ature a nd e xtent o f t he g lass p hase i n b odies a nd s lips, a nd o n s ub-micron p articles r esponsible f or c olour a nd o pacity i n g lazes a nd g lasses . F or e xample, T EM h as s hown t hat t he l ustre d ecoration o n 1 3th c entury I slamic l ustreware i s a ssociated w ith a h igh c oncentration o f v ery s mall m etallic s ilver p articles ( about 0 .02 pm i n d iameter ) d ispersed i n a v ery t hin s urface l ayer o f t he g laze ( Kingery a nd V andiver, 1 986: p 1 19 ). I t m ust b e e mphasised, h owever, t hat s uch r esearch i s m ore c oncerned w ith u nderstanding t he p hysical p rocesses o ccurring d uring f iring, a nd i n i nterpreting t he r esulting m icrostructure , r ather t han c ontributing s ignificantly t o t he u nderstanding o f a ctual p roduction m ethods . T hat i s , t he r esults w ill b e r ather f ar r emoved f rom t he p ractical p roblems o f t he a ncient p otters , a lthough s ome v ery i nteresting s cience w ould b e i nvolved . I n a ddition , t here i s s till s cope f or a s ystematic s tudy o f h ow t he p hysical p roperties ( i .e . p ermeability , s trength , t hermal s hock

1 6

r esistance ) d epend o n t he r aw m aterials a nd f iring p arameters u sed t o m ake p ottery . A lso t here i s av ery r eal n eed f or p hase e quilibrium s tudies i nto s ystems f or w hich t here i s l ittle d ata a vailable i n t he c urrent s cientific l iterature, h ut a re i mportant w ithin a n a rchaeological c ontext . T ypical o f t hese i s t he s ilica/ lime/copper o xide s ystem ( figure 6 ) w hich i s f undamental t o t he u nderstanding o f e arly v itreous m aterials s uch a s f aience a nd E gyptian b lue ( Tite, 1 987 ) -. C onclusions I n s ummary , t he t ime w hen t he d evelopment o f n ew t echniques a nd t he i nvestigation o f s pecific a spects o f c eramic t echnology ( e .g . t he d etermination o f f iring t emperatures ) w ere o f p rime i mportance , i s l ong p ast . I nstead , t he m ain e mphasis n ow n eeds t o b e o n i ntegrated s tudies o f s pecific g roups o f c eramics i n w hich t echnology i s c onsidered w ithin t he o verall a rchaeological c ontext . S uch i nvestigations s hould p rovide ab etter u nderstanding o f t he p eople w ho m ade a nd u sed t he p ottery , a s w ell a s p roviding a n a nswer t o t he q uestions w hy a p articular t echnology w as e mployed a nd, w here a ppropriate, w hy a c hange i n t echnology o ccurred . I n c onsidering w hy a p articular t echnology w as u sed o r w hy a c hange o ccurred, i t i s i mportant t o a void f irst t oo m uch e mphasis o n t echnological r easons s uch a s t he p hysical p roperties o f t he f inished p roduct a nd , s econd , a scribing a n u nrealistic d egree o f t echnological s ophistication a nd u nderstanding t o a ncient p otters . O n t he o ther h and , w hen c onsidering t he r easons f or s ocial o r c ultural c hange i t i s i mportant t o a void p utting t oo g reat a n e mphasis o n t echnology , a t l east a s f ar a s c eramic t echnology i s c oncerned . R ather t han b eing t he c ause o f s ocial o r c ultural c hange i t w ould s eem t hat d evelopments i n c eramic t echnology a re a lmost i nvariably t he r esult o f s ocial c hange ( Kingery , 1 984). T hus i t c an b e a rgued t hat o nce a m arket o r an eed f or d evelopments i n c eramic t echnology a re e stablished a nd i t i s r ecognised t hat s uch d evelopments w ould b e r ewarded , t hen t hey p roceed a t ar apid r ate . T hat i s, t he l evel o f c eramic t echnology r ises t o m eet t he m arket n eeds . F inally , i t s hould b e r eiterated t hat, e ven w ith t his c hange i n e mphasis , t he s cience-trained a rchaeometrist s till h as a c rucial r ole t o p lay , b ut t his m ust b e i n c lose c ollaboration w ith a rchaeologists . I n s pite o f t he v ery r eal d ifficulties i nvolved i n s etting u p a rchaeologically-significant c ollaborative p rojects, i n w hich t he a rchaeometrist a nd a rchaeologist a re e qual p artners , s uch c ollaboration d oes i n m y v iew p rovide t he b est h ope f or t he f uture . O ne a pproach m ight b e t he j oint s upervision b y a rchaeometrists a nd a rchaeologists o f P hD s tudents e ngaged o n t he i ntegrated s tudy o f s pecific g roups o f c eramics . I n t his w ay i t s hould b e p ossible t o a void b oth s cientific a nd a rchaeological n aivety a nd a t t he s ame t ime p rovide t he m ilieu f or b oth s cientific a nd a rchaeological i nnovation . A cknowledgments I a m i ndebted t o D r I an F reestone f or s timulating a nd v aluable d iscussions o n a ll a spects o f t he s tudy o f a ncient c eramic t echnology b oth i n t he c ontext o f t he p resent p aper a nd a t o ther t imes . Ia m v ery

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i n t he T echnology o f A ncient P ottery ,

1 9

Vandiver, P .B . ( 1988) T he i mplications o f v ariation i n c eramic t echnology : t he f orming o f N eolithic s torage v essels i n C hina a nd t he N ear E ast , A rchaeomaterials , 2 , 1 39-74 Wagner, V ., Wagner, F .E . & R iederer, J . ( 1986 ) U se o f Mossbauer s pectroscopy i n a rchaeometric s tudies . I n Olin, J . &B lackman, M . ( eds ) P roceedings o f t he 2 4th I nternational A rchaeometry Symposium , S mithsonian I nstitution P ress : W ashington D .C ., p p 1 29-142 . Woods , A .J . ( 1986 ) F orm , f abric a nd f unction : s ome o bservations o n t he cooking pot i n a ntiquity I n K ingery, W .D . ( ed) C eramics a nd C ivilization Vol 2 , A merican C eramic S ociety : C olumbus , O hio , p p 1 571 72.

2 0

( a )

( b )

Figure 1 . X ero-radiographs o f ( a ) a c ooking p ot ( R inqsdorf-type ) w hich w as t hrown o n aw heel w ith t he b ase s ubsequently p ushed o ut b y h and a nd ( b ) a Medieval j ug ( London w are, l ate 1 3th/early 1 4th c entury ) w hich w as w heel t hrown .

2 1

( a )

( b )

( c )

F igure 2 S EM p hotomicrographs o f p olished s ections t hrough e arly I ron A ge h aematite-coated w are s howing ( a ) i rregular h aematite r ich c oating ( densely p acked w hite p articles ) ( b ) t hick f erruginous c lay s lip c oating ( c ) b urnished s urface w ith n o a pplied c oating .

2 2

1 75 -

TENS ILE S TRENGTH

7

1 50 -

( a )

1 25

1 00 -

A 7 5 0

1 0

4 0

2 0

5 0

% S HELL

. 0 18

A

. 0 14 -

R' ( b ) . 0 10 -

. 006 1 0

2 0

3 0

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% S HELL

F igure 3 Variation i n ( a ) t ensile s trength a nd ( b ) t hermal s hock r esistance ( 1 , 2 - r esistance t o l oss o f s trength o nce c racking h as b een i nitiated ) o f N orth A merican I ndian M oundville p ottery w ith p ercentage o f v isible s hell t emper. 0 = f ine-tempered s erving a nd s torage p ots, e £ =c oarse-tempered c ooking p ots a nd 0 = c oarset empered b owls n ot u sed f or c ooking .

2 3

F igure 4 S EM p hotomicrograph o f p olished s ection t hrough 9 th c entury I slamic g lazed s herds f rom I raq s howing h igh c oncentration o f t in o xide p articles ( white ) i n t he g laze l ayer .

F igure 5 L ate 1 4th/early 1 5th c entury z inc s melting f urnace e xcavated a t Z awar M ala, I ndia s howing r etorts s till i n p lace o n t he p erforated f loor b etween t he u pper a nd l ower c hambers o f t he f urnace .

2 4

S i0 2

±

F aience-body

E l

E gyptian b lue f rit

0

P ole b lue f rit

0

G lassy f aience

M K

E gyptian b lue m ineral

ee,

5

1 1 0

1 1 5

2 0

2 5

3 0

3 5

F igure 6 T ernary d iagram s howing p ercentage w eights ( normalised t o 1 00 % ) o f s ilica, l ime a nd c opper o xide i n e arly v itreous m aterials . T he p osition o f t he E gyptian b lue m ineral p hase ( CaO .Cu0 .4Si0 2 ) i s a lso p lotted.

2 5

T HE A NALYSIS O F A RCHAEOLOGICAL M ATERIALS U SING I NDUCTIVELY C OUPLED P LASMA S PECTROMETRY M .P. H eyworth, J .R . H unter, S .E. W arren S chools o f P hysics & A rchaeological S ciences, U niversity o f B radford a nd J .N. W alsh D epartment o f G eology R oyal H olloway & B edford N ew C ollege, U niversity o f L ondon

T he t echnique o f i nductively c oupled p lasma s pectrometry ( ICPS ) i s b ecoming w idely u sed i n t he i nvestigation o f a rchaeological m aterials . T he I CPS t echnique h as a n umber o f m ajor a nalytical a dvantages w hich i nclude t he w ide r ange o f e lements d etectable, g ood a ccuracy , p recision a nd d etection l imits, a nd f ew i nter-element i nterferences ( for m ore d etails s ee T hompson & W alsh , 1 983 ). R ecently a t B radford U niversity a m ajor a nalytical p rogramme h as b een t o i nvestigate t he p otential o f I CPS f or t he a nalysis o f a r ange o f a rchaeological m aterials . O ur p rimary a nalytical p roject i nvolved t he a nalysis o f m an-made g lass f rom E urope i n t he i st m illennium A D, b ut t his w as a ugmented b y t wo s ubsidiary s tudies o f c eramics a nd s ource o bsidians . C eramics T he u se o f I CPS f or t he a nalysis o f c eramics i s a n atural d evelopment o f i ts r ole i n t he a nalysis o f g eological s amples , f or w hich t echniques h ave b een w ell e stablished ( Thompson a nd W alsh , 1 983 ). O ur a nalytical p rogramme f or c eramics i nvolved t he a nalysis o f b rick a nd t ile f rom t he N orthamptonshire a nd L eicestershire r egions i n a n a ttempt t o a nswer a s pecific a rchaeological p roblem p ertaining t o t he p arish c hurch o f A ll S aints , B rixworth . T his b uilding , w hich i s o f 7 th c entury o rigin , h as b een t he s ubject o f c onsiderable a rchaeological a nd a rchitectural a ssessment ( Rickman , 1 836; Watkins, 1 867; P arsons, 1 979). T he c hurch i s i nteresting n ot o nly b ecause o f i ts e arly o rigins b ut a lso b ecause t he s tone u sed i n t he e arly p hases o f i ts c onstruction w as n ot l ocal a nd m ust e ither h ave b een r obbed f rom o ther i mportant b uildings i n t he a rea o r h ave b een i mported s pecifically f or t he c onstruction ( Sutherland a nd P arsons, 1 984 ). O f p articular i nterest i s t he i dentification o f i gneous r ocks i n t he l ower l evels ( Sutherland , 1 980 ). N o e rratics a re p resent i n t he a rea a nd t he r ock i s o f a t ype f ound i n t he C harnwood a rea t o t he n orth-east o f L eicester, s ome 3 0-40 m iles d istant ( see F igure 1 ) . T he m aterial i n t he l ower S axon l evels o f t he C hurch c ould h ave b een d rawn d irectly f rom q uarry s ites o r e rratics i n t he L eicester a rea o r f rom e xisting R oman b uildings . T he m ost l ikely b uildings a re t hose a t t he i mportant R oman s ettlement a t L eicester ( see F igure 1 ) , a nd t he m ost o bvious s ource , t he h ighest s tanding R oman r emains i n t he c ountry , i s t he J ewry Wall a t L eicester ( Thompson, 1 851 ). A ttention h as b een

2 7

•

NOTT INGHA M

J

7 J e wry Wal l 6 Ro man Foru m S Norfo lk S t. V i l la

S TA MF OR D

L E ICESTER

P ETERB OR OUGH

1 B r ix worth Church 2 B r ix worth V i l la

3 Duston 4 Hunsbury

I ,

B R IX W ORTH

4 ,

NORTHA MPT ON

1 0 m i les

Figure 1 . Map s howing t he l ocation N orthamptonshire a nd L eicestershire .

o f

r elevant

s ites

i n

f ocussed o n t his b ecause o f t he s imilarity i n c onstruction f eatures b etween t he C hurch a nd t he Wall. I n p articular t he b rick a rches a nd h orizontal b onding c ourses i n t he W all m atch t he a rches a t w indows a nd d oors o f t he C hurch . T he w alls o f t he C hurch a lso c ontain h orizontal l ayers o f b ricks o r t iles ( the t erms a re u sed s ynonymously h ere ) w hich a re o f s tandard R oman s ize ( Everson a nd P arsons, 1 979) a nd t his s trongly s uggests t hat t hey w ere r obbed f rom p re-existing R oman b uildings . T he J ewry W all ( or n eighbouring b uildings i n t he F orum ) i s a l ikely s ource b ecause t he s ame s uite o f i gneous r ocks i s t o b e f ound i n i ts c onstruction a s i n t he C hurch . A n umber o f o ther R oman b uildings i n t his r egion c ould h ave a cted a s as ource f or t he t iles ( see F igure 1 ) a nd i t w as h oped t o m atch t he c omposition o f t he t iles a t B rixworth w ith t hose f rom t he J ewry W all o r w ith m aterial f rom o ther R oman s ites . A n

i nitial

s tudy

o f

t he

m aterial

2 8

b y

e nergy

d ispersive

X -ray

f luorescence m um h ad i ndicated t hat t here w ere d ifferences b etween t he s amples f rom t he C hurch a nd s amples f rom s ome o ther R oman b uildings i n t he L eicester a nd N orthampton a rea ( Smith, 1 984 ). O ne p oint o f p articular a nalytical i nterest f rom t his w ork w as t he i dentification o f m agnesium a s o ne o f t he m ost p romising d iscriminating e lements ( see f igure 2 ). H owever, t his e lement w as p resent a t l evels c lose t o t he m inimum d etectable l evel f or E DXRF . T o g o f urther w ith t he a nalysis , r eliable c ompositional d ata w as r equired , i ncluding i nformation o n l ow a tomic n umber e lements s uch a s m agnesium , a nd p referably w ith a n e xtension t o t he r are e arth e lements . I n t hese c ircumstances t he t echnigue o f I CES s eemed i deal .

S E t 4I-CUANTITATIVE A NALYSIS O F T ILE B Y E D ) CRF : G ROUP M EAN C ONCE MATIONS

N orthampton o xide/ B rixworth e lement C hurch

B rixworth V illa

D uston V illa

a rea

L eicester a rea

H unsbury L eicester N orfolk J ewry V illa R oman S treet W all F orum V illa

i n % M gO

1 .15

0 .9

0 .8

0 .3

2 .4

2 .6

3 .0

A 1 203

1 5.3

1 8.7

1 8.4

1 6.5

1 6.3

1 6.1

1 5.1

S iO 2

6 5.5

5 2.2

4 9.1

3 6.8

6 4.6

6 4 .9

6 3.1

K20

2 .6

2 .3

2 .1

1 .3

3 .8

4 .4

4 .3

C aO

5 .5

1 4.0

1 9.9

3 5.9

3 .6

2 .0

5 .0

T iO 2

0 .9

1 .0

0 .9

0 .9

0 .8

0 .9

0 .8

M n0

0 .03

0 .06

0 .03

0 .02

0 .01

0 .06

0 .11

F e 2O3

7 .9

9 .6

7 .4

7 .1

7 .2

8 .0

7 .4

R b

1 60

2 00

1 70

1 60

1 80

2 00

1 90

S r

2 00

4 40

6 00

1 040

1 20

1 10

1 60

3 8

4 2

3 4

5 1

3 3

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3 0

4 20

2 50

2 70

2 80

2 50

3 30

2 70

1 _ 1

Y Z r

F igure 2 . I nitial E DXRF d ata f or b ricks a nd t iles

2 9

( Smith, 1 984 )

A n umber o f s amples f rom s ites i n t he r egion w ere a nalysed b y I CPS ( Figure 3 ) a nd t he o bvious c onclusion f rom t he r esults , a nd t he f irst o bjective o f t he a nalysis, w as t hat t he t ile i n t he C hurch d id n ot o riginate f rom t he J ewry W all ( Smith a nd Warren , f orthcoming ). H owever t he s ituation i s c omplicated b y t he f act t here t here a re t wo p hases o f c onstruction a t t he J ewry W all s ite ( Kenyon , 1 948 ) a nd o nly P hase I h ad b een s ampled . F urther s ampling a nd a nalysis w as u ndertaken b y R ees ( 1986 ) a nd t his w ork s upported t hese o bservations . T he p roject h as n ow b een e xtended ( C rotty , 1 986 ) t o i nclude o ther R oman s ites a nd p roducts o f k ilns/clay p its i n t he g eneral r egion . CANONICAL

3

3

F UNCTION 2

2 4, Z4

DISCRIMINANT

3

2 , 2 )

2 2

244

4 '

33

1

5 6 5 5 7 5 5 5 5

2

5

4

2 44

FUNCTION

5 67 7 776 67 1

7 7

7

7 77

7

2

K ey : 1B r ixworth C hurch 2B r ixworth V i l la 3D uston,

11 11

1

1

11

N orthampton

4H unsbu ry , N orthampton 5N orfo lk S t . V i l la , L e icester 6R oman F orum , L e icester 7 J ew ry Wa l l , L e icester F igure 3 . D iscriminant a nalysis o n t he I CPS d ata f or a ll b rick/tile s amples

Although t his w ork c ontributes t o t he w ider k nowledge o f t he c ompositions u sed b y t he R omans i n t heir p roduction o f b rick a nd t ile, r eveals s mall c hemical d ifferences b etween t he t ile f rom t he t wo p hases o f c onstruction a t t he J ewry Wall a nd s uggests a n a rea t o t he e ast o f L eicester w hich m ay h ave p rovided t he b rick a nd t ile f or t he m assive b uildings o f R oman L eicester, i t d oes n ot t hrow s ignificant n ew l ight o n t he o riginal p roblem - w as t he b rick/tile i n t he s tructure o f t he S axon C hurch a t B rixworth r obbed f rom R oman s ites i n L eicester? A nalytically t he t iles a re d issimilar i n c omposition t o t hose f rom o ther s ampled s ites b ut t he c lose a ssociation o f L eicester r egion r ocks w ith t he b rick r emains t he m ost c onvincing a rgument f or t he o rigin o f t he b rick b eing L eicester .

3 0

O bsidian O bsidian i s a h igh s ilica c ontent v olcanic G lass w ith s ources i n r egions s uch a s t he M editerranean a nd C entral E urope ( figure 4 ) . I t i s a p articularly s uitable m aterial f or w orking i nto a rtifacts a nd t here i s c onsiderable a rchaeological e vidence f or i ts t rading i n p rehistory ( Dixon, C ann a nd R enfrew, 1 968). O bsidian h as t hus e xcited m uch a nalytical i nterest a nd w ork b egan i n t he e arly 1 960 's t o c haracterise t he v arious o bsidian s ources b y t heir c hemical c omposition . T echniques s uch a s O ES ( Renfrew , D ixon a nd C ann, 1 968 ), N AA ( Hallam , Warren a nd R enfrew , 1 976 ) a nd X RF ( 3helford e t a l, 1 982 ) h ave a ll b een e xploited t o c haracterise o bsidian f rom d ifferent r egions u sing p articular e lements.

CARPATH IAN •

•

SOURCES

IA XE VAN IC AC IC OL. C IFTl iK e

F igure 4 . L ocation o f o bsidian s ources i n E urope. O ur p rimary i ntention i n t he r eanalysis o f s ource o bsidians f rom t he W estern M editerranean, t he A egean a nd C entral E urope w as t o p rovide a c omprehensive s uite o f e lements f rom w hich t o d emonstrate t he f easibility o f I CPS f or p rovenance s tudies . O bsidian w as r egarded a s a p articularly s uitable c hoice o f m aterial t o b e a nalysed b ecause s everal o f t he f lows w ere k nown t o h e h omogeneous, a nalyses h ad a lready b een c arried o ut b y d ifferent t echniques f or m ore r estricted r anges o f e lements a nd t he s ource m aterial w as s ufficiently p lentiful f or a nalysis b y c onventional a nd r are e arth e nrichment t echniques. A nalyses w ere u ndertaken o n m aterial f rom s even s ource a reas . S everal w orkers h ave s hown t hat d iscrimination i s p ossible n ot o nly t hrough t race e lement c ompositions ( Cann & R enfrew , 1 964 ) w hich w ould

3 1

b e e xpected t o p rovide g reater i nter-source v ariability, b ut a lso t hrough m ajor/minor e lements p rovided t hat t hey w ere c hosen w ith d ue r egard t o t he k nown o bsidian d istribution z ones o r w ere a nalysed w ith s ufficient p recision ( Francaviglia , 1 983 ). T he d iscrimination b etween s ources r esulting f rom t he I CPS d ata c an r eadily b e s een f rom t he r esults o f t he d iscriminant a nalysis u sing a ll e lements ( figure 5 ) a nd s imilar d iscrimination w as o btained f rom t he r are e arth e lements a fter e nrichment . E nrichment i ncreases t he r are e arth e lement c oncentrations b y a f actor o f t en i n t he a nalytical s olution a nd a llows I CPS t o c over a m ore c omprehensive s et o f r are e arth e lements t han t hat r eadily o btainable b y n eutron a ctivation a nalysis ( Walsh e t a l, 1 981 ). R ecent a nalyses o f t he o bsidian f rom S ardinia u sing N AA ( Mackey a nd W arren, 1 982 ) c an b e c ompared t o t he d ata o btained f rom I CPS ( figure 6 ). T he f uller r ange o f r are e arth e lements o btained b y I CPS a llows b etter d efinition o f t he c hondrite n ormalised p lots a nd o f t he l arge e uropium a nomaly f ound f or t he C onca C annas f low , w hile c onfirming t he o verall s imilarity o f t he o bsidians f ound i n t he S anta Maria Z uarbara a nd P erdas U rias r egions o f S ardinia . T he a pplication o f t he I CPS t echnique t o t he a nalysis o f s ource o bsidians d emonstrates t hat I CPS h as s ufficient p recision o ver a v ery w ide r ange o f c hemical e lements t o r esolve d ifferences i n c ompositions o f d ifferent o bsidian f lows w hether t hey b e a t m ajor, m inor o r t race l evel . CAN ONICAL

D ISC RI MI NA NT

FU N CTI O N

1

5 55 5 5 1 6

7 77 7 7 7 77 7777

FUNCTI ON

8

0

666 6

4 4 1 4 1 444 8

3

2 2 2 222

3

16

8

0

Group 1— Vulcano Group 2— Sardinia Group 3— P al marola Group 4—Lipari

8

Group

5 — Melos

Group

6 — G iali

Group

7 — Central

1 6

Europe

F igure 5 . D iscriminant a nalysis o n m ajor/minor e lement d ata f or o bsidian s ource g roups

3 2

s even

1 000

1 000

1 00

1 00

GROUP

( CONCA CANNAS )

1 0

La t 000

1 00

1 0

SA

L 3 , 0

L a

E u

t u moo

1 00

GROUP

SB

( S . H Z . ) 1 0

Eu

La

1 0

L a

L u

Eu

1 000

1 000

1 00

1 00

GROUP

SC

( PER DAS URIAS)

1 0

L a

Eu NAA

Mackey

data

Lu

1 0

La

Eu

L u

f rom I CPS

a nd Warren ( 1982 )

Data

F igure 6 . C hondrite n ormalised p lots f rom M ackay & Warren c ompared w ith I CPS d ata f or S ardinian o bsidian .

( 1982)

G lass W hilst t he p otential o f t he m ulti-element a pproach a llowed b y I CPS i s c lear f or o bsidian i t b ecomes e ven m ore u seful w hen i nvestigating t he c omposition o f m an-made g lasses . G lass i s p articularly d ifficult t o i nterpret a nalytically a s i t i s f ormed f rom s everal c omponents . W hilst t he e arly g lassmakers w ere v ery t raditional a nd r elied o n w ell u sed a nd t rusted p roduction f ormulae ( Hunter, 1 981 ) t here w ere i nevitably s ome v ariations i n t he c ompositions o f t he r aw m aterials u sed . T he d eliberate i ntroduction o f c ertain e lements a nd t he w idespread r euse o f g lass a s c ullet a dd t o t he a nalyst 's p roblems . S amples f rom e ither s ettlement o r f urnace s ites m ay n ot n ecessarily r epresent l ocal p roducts , a nd t he m ixing o f g lass f ragments f rom d ifferent s ources w ill

3 3

r esult i n m isleading i ntermediate c ompositions . I n B ritain t here i s very l ittle evidence f or g lassmaking ( as o pposed t o g lassworking ) i n t he i mmediate p ost-Roman p eriod . A part f rom a p ossible f urnace a t G lastonbury ( Radford, 1 958 ) a nd t he p roblematic ' proto-manufacturing ' e cclesiastical s ites w here w indow g lass m ay h ave b een m ade, s uch a s Monkwearmouth a nd J arrow ( Cramp , 1 970; 1 975 ), e vidence f or t he w orking o f g lass c omes f rom s ites s uch a s V isemarest i n n orthern F rance a nd S outhampton i n s outhern E ngland w here c rucibles c ontaining m elted g lass h ave b een f ound ( Maude , 1 987 ; H unter a nd H eyworth f orthcoming ). G iven t he l imited e vidence f or g lass m anufacture i n t his p eriod, a nd t he s imilarity o f t ypological f orms p resent i n m id-Saxon a ssemblages, i t w as h oped t hat a multi-element a pproach t o t he a nalysis o f a l arge g roup o f g lass f rom e xcavations i n B ritain a nd N orthern E urope w ould g ive s ome c lues a s t o t he p roduction c entres i n u se i n t he m id-Saxon p eriod . I CPS w as a gain c onsidered t o b e t he i deal t echnique t o u se i n t hese c ircumstances w ith a dvantages i n t he r elative e ase o f h andling s mall s amples i n g reater n umbers t han w ith m any o ther t echniques . T he r ange o f e lements d etectable b y as ingle t echnique i s e qually i mportant, p articularly i n r elation t o g lass w here c orrelations b etween m ajor, m inor a nd t race e lements a re f undamental t o t he d etermination o f r aw m aterial t ypes a nd a ssociated i mpurities . I n t he p ast t hese h ave u sually h ad t o b e d erived f rom t wo s eparate t echniques, X -ray f luorescence ( XRF ) a nd n eutron a ctivation a nalysis ( NAA ), e ach w ith d iffering s ystematic e rrors . N early 6 00 a rchaeological s amples w ere a nalysed i n t his p roject o f w hich t he m ajority c ame f rom t he S axon t owns o f S outhampton a nd W inchester i n A nglo-Saxon Wessex . T he d ata s uite o f 2 8 e lements o btained f rom t he I CPS a nalysis p rovides a v aluable e xtension t o d ata o btained f rom c omparable m aterial a nalysed s eparately u sing X RF a nd N M t echniques ( Sanderson e t a l, 1 984 ; S anderson a nd H unter, 1 982 ). W inchester w as a r oyal a nd e cclesiastical c entre w ith s ufficient p atronage t o f oster g lazing . T he g lass c omes f rom r eliable c ontexts u ncovered d uring l arge s cale e xcavations i n t he t own c onducted b y M artin B iddle , a nd i ncludes b oth w indow a nd v essel g lass f ragments f rom t he p eriod A D 4 00-1200 . A nalysis w as u ndertaken o n 4 4 s amples o f W inchester w indow g lass r epresenting f ragments f rom f our o f t he t ypological g roupings a ssigned b y H unter & B iddle ( forthcoming ). T hese f ragments c ame f rom a n umber o f s ites e xcavated w ithin t he c ity a nd i t w as h oped t hat t he c ompositional d ata c ould b e u sed t o t est t he t ypological a nd a rchaeological i nterpretation o f t he m aterial . A ll t he g lass i s s imilar i n m ajor a nd m inor e lement c omposition a nd i s o f t he g eneral, d urable , s oda-lime-silica t ype . H owever, t here a re s ignificant v ariations b etween t he c ompositions o f t he f our t ypological g roups, a lthough e ach h as a t ight c ompositional r ange ( figure 7 ). W hilst a ll t he g lasses a re s imilar a t t he m ajor e lement l evel, t he G roup 3 f ragments c an b e d istinguished f rom a ll t he G roup 2 f ragments o n t he b asis o f h igher c opper, c obalt a nd a ntimony c ontents . T his s uggests t hat t he g lassmaker m ade a d eliberate a ttempt t o m odify t he c olour o f t he f ragments i n G roup 3 . H owever, G roup 2 B i s v ery s imilar t o G roup 3 i n m agnesia, p otash a nd p hosphate c ontent , w ith a ll t hree

3 4

C OMPOSITIONAL D ATA F OR T HE F OUR TYPOLOGICAL GROUPS O F W INCHESTER W INCO A T g roup 2 A

G LASS

g roup

g roup

2 B

2 C

g roup 3

i n% A l 203

3 .09 + 0 .46

2 .55 + 0 .09

2 .62 + 0 .30

2 .45 + 0 .16

0 .82 + 0 .36

1 .24 + 0 .09

F e 2O3

0 .87 + 0 .31

0 .78 + 0 .07

M gO

0 .69 + 0 .19

0 .98 + 0 .29

0 .64 + 0 .10

0 .95 + 0 .38

C aO

6 .94 + 0 .74

7 .77 + 0 .68

7 .33 + 0 .78

7 .24 + 1 .05

N a 2O

1 7.0 + 2 .3

1 6.7 + 1 .2

1 7.6 + 1 .4

1 7.1 + 1 .8

K2 0 T iO 2

0 .68 + 0 .06

1 .51 + 0 .75

0 .64 + 0 .12

1 .10 + 0 .68

0 .15 + 0 .06

0 .10 + 0 .01

0 .11 + 0 .05

0 .12 + 0 .03

0 .11 + 0 .12

0 .37 + 0 .22

0 .18 + 0 .21

0 .58 + 0 .25

6 9.9 + 2 .2

6 8.8 + 1 .0

6 9.4 + 1 .3

6 8.7 + 1 .2

M nO

0 .43 + 0 .58

0 .48 + 0 .07

0 .65 + 0 .46

0 .52 + 0 .05

P b

0 .20 + 0 .23

0 .16 + 0 .03

0 .27 + 0 .30

0 .44 + 0 .12

S b

0 .06 + 0 .09

0 .23 + 0 .08

0 .23 + 0 .19

0 .83 + 0 .25

P205 S iO 2

B a

3 05 + 4 7

3 44 + 6 7

3 36 + 1 86

3 04 + 9 5

C e

1 8 + 3

1 9 + 2

1 7 + 2

1 8 + 2

C o

1 1 + 3

1 0 + 1

1 2 + 4

3 35 + 1 64

C r

4 6 +9

4 7 + 3

4 7 + 4

4 9 + 5

C u

3 01 + 3 63

1 1 86 + 7

5 45 + 8 87

1 576 + 5 20

L a

7+ 1

7+ 1

6+ 1

6+ 1

L i

1 0 + 3

1 2 + 1

1 0 + 4

1 4 + 1 0

N b

3+1

3+ 0

3+1

3+ 1

N i

2 4 + 4

2 8 + 3

2 7 + 4

6 5 + 7

S c

1+1

1+1

1+1

2+1

S r

4 25 + 3 9

4 4 30 + 1

4 41 + 3 5

4 33 + 1 5

V

1 8 + 7

1 9 + 2

2 2 + 6

1 9 + 2 1 9 + 1

1 0 +0

9+ 1

9+1

Z n

7 3 2 + 2

0 6 1 + 2

3 4 + 2 1

7 7 + 1 5

Z r

2 6 6 + 2

5 0 + 6

5 2 + 2 4

5 3 +1 2

n o o f

4

1 6

1 3

1 1

s amples F igure 7 . I CPS d ata f or f our t ypological g roups o f W inchester w indow g lass.

3 5

C OMPOSITION O F T EN G LASS F RAGMENTS F ROM W OLVESEY P ALACE

W P

W P

N P

W P

W P

W P

W P

W P

W P

T A T

4 166

2 341

4 159

8 92

1 716

1 055

1 051

1 084

1 064

5 049

A l 203

2 .56

2 .57

2 .55

2 .59

2 .66

2 .72

2 .56

2 .48

2 .57

2 .51

F e 203

0 .75

0 .88

0 .74

0 .76

0 .79

0 .79

0 .79

0 .74

0 .75

0 .74

M q0

1 .15

0 .62

1 .48

1 .08

1 .09

1 .17

1 .06

1 .04

1 .14

1 .13

i n %

C a0

8 .01

7 .56

8 .95

7 .97

8 .27

8 .27

8 .05

7 .80

7 .94

7 .95

16.4

1 6.9

1 5.5

1 6.6

1 6.7

1 5.7

1 6.3

1 6.2

1 5.9

1 5.3

g2 0

1 .34

0 .66

2 .77

1 .39

2 .19

2 .14

1 .41

1 .39

1 .64

2 .66

T iO 2

0 .10

0 .10

0 .09

0 .11

0 .10

0 .11

0 .09

0 .10

0 .11

0 .11

N a 20 -

P205

0 .54

0 .12

0 .70

0 .43

0 .42

0 .53

0 .42

0 .42

0 .56

0 .53

S i0 2

6 8.7

7 0.1

6 6.7

6 8.6

6 7.3

6 8.1

6 8.9

6 9.4

6 8.9

6 8.6

M n0

0 .50

0 .49

0 .53

0 .49

0 .50

0 .51

0 .49

0 .48

0 .50

0 .48

P b

0 .15

0 .27

0 .14

0 .15

0 .15

0 .15

0 .15

0 .15

0 .15

0 .15

S b

0 .20

0 .33

0 .18

0 .19

0 .16

0 .17

0 .19

0 .20

0 .16

0 .22

B a

4 00

2 66

3 99

3 78

3 16

4 06

3 73

3 72

4 12

3 90

C e

1 9

1 9

2 2

1 9

2 0

2 1

1 9

1 8

1 8

1 9

C o

1 0

1 2

1 0

1 1

1 0

1 1

1 0

1 0

1 1

IM

9

C r

4 6

4 6

5 5

4 7

4 8

4 8

4 9

4 8

4 9

4 9

C u

2 21

2 55

1 49

2 21

2 21

2 31

2 17

2 21

2 44

2 37

L a L i N b N i S c S r V X

7 1 2 3 2 9 0

6 1 2 3 2 8 0

7 1 1 3 3 1 0

7 1 3 3 2 9 0

4 42

4 25

4 40

4 41

1 8

2 0

2 0

1 9

9

9

9

9

6 1 3

7 1 1

3 3 0

3 3 2

0 4 51

0 4 29

6 1 2 3 2 7 0

7

7

1 2

1 1

3

3

2 7

2 8

2

2

6 1 2 3 2 9 2

4 37

4 27

4 30

4 19

1 8

1 9

1 8

2 0

2 1

1 9

1 0

1 0

1 0

9

9

9

Z n

7 0

5 8

8 9

7 0

7 4

7 0

7 0

6 5

7 1

7 5

Z r

5 6

5 5

3 8

5 5

3 9

4 0

4 9

5 1

5 5

5 3

F igure 8 . I CPS d ata f or t en W olvesey P alace g lass f ragments

3 6

o xides h aving h igher c oncentrations t han i n g roups 2 A a nd 2 C . H unter a nd B iddle ( forthcoming ) h ave a rgued t hat G roups 2 A a nd 2 C m ay b e p art o f t he s ame g lazing t radition a nd s eparate f rom G roups 2 B a nd 3 w hich m ay t hemselves b e s imilar . T he c ompositional d ata w ould s upport t his a rgument. G roups 2 B a nd 3 f orm e specially t ight c ompositional g roups s uggestive o f s eparate b ut c ontrolled g lass b atches b eing u sed f or t heir p roduction . I n p articular, t he c ompositions o f t en f ragments f rom Wolvesey P alace a re c ontained w ithin G roup 2 B ( figure 8 ). T his s upports t he p ossibility o f as ingle g lasshouse s upplying g lass f or t he b uilding . H unter a nd B iddle h ave a rgued f or a n e piscopal g lasshouse i n t he a rea a nd t hese f ragments m ay r epresent t he p roduct o f s uch a c ontrolled w orkshop . A s t here a re n o m ajor c ompositional d ifferences i n t he b asic c omponents o f t he glass r ecovered f rom s ites i n W inchester, i t r equires a n a nalysis f or a c omprehensive r ange o f e lements t o d raw d istinctions b etween g roups o f s amples . T his i ndicates t he v alue o f a m ulti-element a pproach a s i s p ossible b y I CPS b ut l ess r eadily a chieved b y s ome o ther m ethods o r c ombinations o f m ethods . I t m ay b e p ossible f rom t he e xtended r ange o f e lements t o u se t he c orrelations b etween , o n t he o ne h and , t he s pecific m inor/trace e lements l ikely t o h ave a ffected t he c olouring a nd , o n t he o ther h and , t he m ajor e lements b elonging t o r aw m aterial t ypes, t o a ssign s pecific t race i mpurities w ith k nown c olouring p roperties t o i ndividual r aw m aterial t ypes . I n t he a bsence o f r aw m aterial k nowledge, t he m ain p roblem i s i n a ttempting t o d esignate l evels a t w hich t he c oncentration o f ac olouring e lement c eases t o r epresent a n i mpurity a nd i nstead r epresents a d eliberate a ddition. T he a nalytical w ork h as s hown t hat t here i s as trong p ossibility o f l ocalised m anufacture o f t he g lass f rom W inchester . H owever, w ithout a d etailed k nowledge o f t he a rchaeological c ontext , i t i s v ery d ifficult t o b uild u p ap icture o f t he n ature o f t he g lass i ndustry o perating a t t his t ime . I t m ay b e t hat t here w as a g roup o f g lassworkers w ho, t hrough p atronage , c ould r ely o n c ontinued s upplies o f r aw m aterials a nd w ho p roduced a nd m elted g lass i n t he a rea, o r p erhaps i t w as a r eworking p rocess t hat t ook place w ith c akes o r even c ullet b eing t ransported e specially f or t he p urpose . T hese q uestions c annot b e a nswered f rom c hemical a nalysis a lone, a nd i t i s p articularly i mportant t o c onsider t he a rchaeological a nd h istorical e vidence a longside t he a nalytical e vidence i n t he s tudy o f t he a ncient g lass i ndustry . C onclusion T hese a rchaeological e xamples s how t he p otential o f t he I CPS t echnique f or t he i nvestigation o f a rchaeological m aterials . O ther p apers i n t his v olume p rovide f urther e xamples o f i ts a pplication . I CPS p rovides h igh q uality d ata f or a w ide r ange o f e lements t o a llow a b etter u nderstanding o f t he r aw m aterials i nvolved . C omprehensive a nalytical d ata , c oupled w ith a d etailed s tudy o f t he a rchaeological e vidence , c an g o a l ong w ay t o h elp u s u nderstand t he n ature o f a ncient i ndustries a nd m aterial u sage .

3 7

A cknowledgments T he a uthors g ratefully a cknowledge t he s upport r eceived t hrough t he S cience-Based A rchaeology C ommittee o f t he S cience a nd E ngineering R esearch C ouncil f or t he r esearch r eported i n t his c ontribution . R EFERENCES C ann J .R . &R enfrew A .C . ( 1964) T he c haracterisation o f o bsidian a nd i ts a pplication t o t he Mediterranean r egions P roc .Prehist .Soc . 3 0 1 11-33 C ramp , R .J . ( 1970) D ecorated w indow g lass M onkswearmouth , A ntiquaries J ournal 5 0, 3 27-35 .

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C ramp , R .J . ( 1975) W indow g lass f rom t he m onastic s ite o f J arrow , J ournal o f G lass S tudies 1 7 , 8 8-96 . C rotty, P .J. ( 1986) Analysis o f t ile f rom B rixworth C hurch, N orthamptonshire a nd f rom various R oman s ites b y I nductively C oupled P lasma E mission S pectrometry , M A D issertation , U niversity o f B radford . D ixon, J .E ., C ann, J .R . &R enfrew , C . o f t rade, S cientific A merican 2 18(3 ),

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( 1968) F urther Analysis o f Near 3 4, 3 19-331 .

R ickman, T . ( 1836) F urther observations o n t he e cclesiastical a rchitecture o f F rance a nd E ngland , A rchaeologia , X XVI . S anderson, D .C .W . S tH unter, J .R . ( 1982 ) Neutron A ctivation Analysis o f g lass f rom B ritain a nd S candinavia , P ACT 7 , 4 01-11 . S anderson, D .C .W ., H unter, J .R . & Warren, S .E . ( 1984) E nergy d ispersive X -ray f luorescence a nalysis o f 1 st m illennium A D g lass f rom B ritain, J ournal o f A rchaeological S cience 1 1, 5 3-69 . S helford, P ., H odson, F ., Cosgrove, M .E ., Warren, S .E . & R enfrew , C . ( 1982 ) T he O bsidian T rade : t he s ources a nd c haracterisation o f Melian o bsidian . I n R enfrew , C . & Wagstaff, M . ( eds ) An I sland Polity, C ambridge U niversity P ress , 1 82-92 . S mith , L .M .V . ( 1984 ) X -ray F luorescence A nalysis o f T ile f rom B rixworth C hurch , MA D issertation , U niversity o f B radford . Smith, L .M .V . &Warren, S .E . ( forthcoming ) An a nalytical s tudy o f t he b rick a nd t ile f rom B rixworth Church . I n P arsons, D . ( ed ) Report o f t he B rixworth E xcavation C ommittee . S utherland D . ( 1980 ) May/June 5 9-63

W hat t he s tones

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3 9

W atkins , C .F . ( 1867 ) T he b asilica a nd a d escription a nd h istory o f t he b asilican c hurch o f B rixworth , L ondon .

4 0

A NALYSIS O F R OMAN P OTTERY F ROM C OLCHESTER B Y I NDUCTIVELY-COUPLED P LASMA S PECTROMETRY

D .M . S mith", F .A.Part 2 , P .P . S ymonds 3 a nd

J .N.Walsh l

' Geology D epartment, R oyal H olloway & B edford N ew C ollege, L ondon U niversity 2C hemistry

D epartment, Q ueen M ary C ollege, L ondon U niversity .

3C olchester

A rchaeological T rust C olchester

A bstract T his i s a s tudy , u sing c hemical d ata, o n s ome o f t he i nhomogeneous c ollection o f R owan p ottery w hich h as b een f ound i n C olchester s ince 1 971 . I t i s h oped t o f ind o ut, u sing c hemical d ata o btained b y i nductively—coupled p lasma ( IT ) a nalysis , t o w hat e xtent t he c hemistry o f t he p ots c an a ssist p ottery a nalysts i n t heir g rouping a nd p rovenancing, a nd a lso i n t he d iscovery o f t he s ource c lays . O ne o f t he m ajor o bjectives i s t o e stablish a d atabase f or f uture r esearch, c ombining t he c hemical d ata w ith t he a rchaeological i nformation g athered b y t he t eam a t C olchester . T he a rchaeologist d oes n ot n eed t o k now a nything a bout c hemistry t o u se t he d ata g enerated; i t c an b e r egarded a s f urther a rchaeological i nformation t hat j ust h appens t o b e e xpressed Q uantitatively . I ntroduction N atural s ubstances, i ncluding r ocks a nd c lays f rom w hich p ottery i s p roduced , a re m ade u p o f m inerals o f d ifferent t ypes . T he e lements a re h eld i n v arious c ombinations i n t he l attice s tructure o f m inerals, t hese m inerals o ften h aving a s ilicate s tructure . T he p roportions o f c hemicals i n as ubstance g ive i t as pecific ' signature ' w hich c an b e r ecognized. I n p ottery , t he d ominant m inerals w hich g ive t he w orking f abric i ts p lasticity a re t he " clay m inerals"; t hese a re s heet o r l ayer h ydrous a luminium s ilicates . T hese m inerals f orm t he b ulk o f t he f abric , w hich a lso h as o ther e lements a nd m inerals w ithin i t , i n v arious p roportions . B ecause o f t heir i m p ortance i n c eramics a nd a griculture, c lays h ave b een e xtensively i nvestigated . I t h as b een f ound t hat c lays o f t he s ame c hemical c omposition f requently h ave d ifferent p hysical a ttributes a nd t hat c lays w ith s ubstantially t he s ame p hysical p roperties h ave v ery d ifferent c hemical c ompositions . T he l atter f act i s v ery i mportant t o b oth t he p otter a nd t he c hemical a nalyst ; i t i s a lso o ne o f t he r easons w hy t his t ype o f s tudy

4 1

c an b e u sefully u ndertaken . I t m eans t hat t he p otter c an u se a ny s uitable c lay i n t he l ocal v icinity ; t he m aterial f rom o ne s ource w ill o ften ' handle ' o r ' work ' a s w ell a s c lay f rom 5 0 k m a way , c lay w hich i s o f a c ompletely d ifferent g eological a ge , c haracter a nd c hemistry . M ulti-element a nalysis c arried o ut , u sing I CP s pectrometry , c an d efine t hat c hemistry ( Thompson & W alsh, 1 983 ). I t s hould t herefore b e p ossible t o d istinguish b etween p ots o f t he s ame f orm , b ut o f d ifferent p rovenance , a nd p ots o f s imilar f abric , b ut m ade f rom d ifferent s ource c lays . A s f ar a s t his p articular w ork i s c oncerned , i t s hould a lso b e p ossible t o t ypify t he ' Colchester S tandard a nd R ange ' f or e ach p ot f abric . T his c an t hen b e u sed a s a n ormalization s tandard a nd a r eference f or f uture r esearch a nd s tatistical a nalysis . I n I CP s pectrometry t he s ample i s ' stimulated ' i n ap lasma , a nd t he l ight t hen e mitted b y t he ' stimulated ' s ample i s a nalysed i n o rder t o m easure t he c oncentration o f t he e lements i n i t . T he h eart o f t he I CP s pectrometer - t he ' flame ' - m akes i t possible t o d etermine, s imultaneously , t he c oncentration o f u p t o 3 0 e lements i n s olution i n o ne m inute o f m achine t ime Walsh & H owie, 1 986). I CP a nalysis i s a s olution m ethod , a nd p reparation h as t o b e c arried o ut u sing a m ethod w hich d igests t he s ample i n a f inely p owdered f orm . S ample p reparation S ampling o f C olchester p ottery h as b een c arried o ut b y u sing a t ungsten c arbide b urr i n a n e lectric d rill m ounted i n ad rill s tand, w ith t he s herd b eing ' hand h eld '. T his m ethod h as g reat a dvantages . I t i s a ' dry ' m ethod, w hich p roduces ' ready p repared ' s amples f rom b oth f ine a nd c oarse w ares . T he p owder, a s d rilled, i s f ine e nough t o b e d igested, w ithout f urther c rushing, s aving p reparation t ime . T he p roblem o f h omogeneity o f s ample i s a lso o vercome, e ven i n c oarser f abrics . T his c an b e s een f rom r epeated s ample d etermination v alues f or s ome o f t he m ortaria s herds ( figure 1 ) w hich g ives v alues w ithin o r e qual t o p recision l imits o f 1 -2% f or m ajor e lements a nd a pproximately 5 % f or t race e lements . ( In t hese r epeat d eterminations s ome s amples w ere a nalysed t wice a nd , i n o ther c ases , m ultiple s amples w ere t aken f rom a s ingle s herd ). T he s ampling t echnique d escribed a bove i s a lso l ess d estructive t han d iamond c oring b its , w hich a re u sed ' lubricated ', w ith d istilled w ater a nd p roduce a t reated s herd , r eminiscent o f S wiss c heese ! T he ' plug ' e xtracted b y t his m ethod m ust t hen b e s urface c leaned a nd s ubs e quently c rushed t o p roduce a p owder . A s t he s herds a re h and h eld , e ven v ery s mall, f ine f ragments c an b e s ampled . T he e lectric d rill m ethod c an a lso b e u sed v ery d iscreetly . W hole p ots, o r p ots r equired f or e xhibition, c an b e s ampled w ithout o bvious d amage , b ecause o nly a v ery s mall s urface q uantity i s r equired f or a nalysis ( 0 .1 g ). I t s hould b e p ossible ( given a p ortable g enerator ) t o u se t his m ethod o n a n a rchaeological s ite . S mall s amples c an t hen b e s ent b ack t o b ase a nd p repared f or a nalysis a s e xcavation c ontinues . T his c uts d own t he l ead t ime b efore r esults a re o btained . T he c hemistry o f t he b ody f abric i s t he t hing t hat w e a re m ost i nterested i n . O ften t he s herds o r p ots h ave b een ' slip c oated ', o r t he s urface i s d egraded b y b urial p rocesses . S ome s how a ' skin t o f m anganese d ioxide o r c alcium c arbonate s cale . I t i s v ery e asy t o r emove s uch s urface c oatings u sing t his d rilling m ethod , t o g et a t t he

4 2

4 07

4 07P

4 25

4 25R

4 38

4 38R

4 68

4 68R

5 27

5 27R

w t %

T o

A l 203

5 3.36 5 4.77

5 7.01 5 6.22

7 7.54 7 6.08

6 5.43 6 5.13

5 7.25 5 7.85

1 2.88 1 2.62

1 5.12 1 5.45

1 7.33 1 8.42

2 6.56 2 6.81

1 2.65 1 2.43

F e 2O3

4 .46

4 .37

5 .40

5 .55

2 .95

3 .10

3 .33

3 .36

4 .98

4 .89

M g0

1 .37

1 .32

1 .21

1 .25

0 .41

0 .44

0 .62

0 .63

1 .01

1 .00

1 4.64 1 4.78

0 .47

0 .53

0 .60

0 .63

C aO

2 4.40 2 3.47

2 0.29 2 0.11

N a 2O

0 .41

0 .39

0 .34

0 .35

0 .09

0 .09

0 .25

0 .24

0 .35

0 .34

K20

1 .84

1 .80

1 .48

1 .52

0 .35

0 .40

2 .07

2 .08

1 .56

1 .51

T iO 2

0 .64

0 .63

0 .71

0 .74

0 .72

0 .79

1 .01

0 .99

0 .60

0 .59

P205

0 .57

0 .56

3 .99

4 .02

0 .13

0 .14

0 .11

0 .11

1 .22

1 .20

M nO

0 .07

0 .07

0 .10

0 .11

0 .01

0 .01

0 .02

0 .02

0 .09

0 .08

F Pm B a L i N b S c Y

3 22 8 0 1 1 1 3 2 7

7 79 5 7 1 1 1 5 9 2

8 08 5 9 1 0 1 6 9 3

1 37 3 2 1 2 1 4 8 3

1 46 3 5 1 3 1 5 9 3

3 93 6 4 1 0 1 3 2 6

3 85 6 2 1 0 1 2 2 6

3 24 7 9 9 1 3 2 6

F igure 1 . R epeat m easurements . e lements i n p pm

4 48 1 38 1 2 2 9 8

3 75 1 37 1 1 2 8 8

Major o xides g iven a s % ;

s elected t race

b ody f abric . O n t he o ther h and, i t i s e qually e asy t o s ample ' slip c oatings' f or c omparison w ith b oth b ody f abrics a nd o ther ' slip c oats'. T he p ossibility o f c ontamination f rom t he u se o f t ungsten c arbide b urrs h as b een a ssessed i n a c omparative s tudy , u sing 1 0 t itle s amples g round b y b oth a s pecial s teel T ema m ill a nd t ungsten c arbide b urrs . P revious w ork ( Storey , p ers . C OMO e stablished t hat n o c ontamination o ccurs u sing a T ema m ill . M easurable c ontamination o nly o ccurs i n t he c ase o f C o a nd C r f rom t he d rill ( figure 2 ) . 0 .1 g o f s ample i s w eighed o ut i nto a P TFE c rucible a nd t hen d igested w ith H F/HC10 4 o n a h ot-plate . T his b reaks d own t he s ilicates a nd f rees t he e lements h eld i n t he m ineral l attices . T he r esidue i s d issolved i n 1 0% H C1 a nd c an t hen b e a nalysed o n t he I CP. U se o f a nalytical p ro s :ga mes F or t his s tudy t he T races P E p rogram w as u sed ; t his i s o ne o f t he s tandard a nalytical p rograms available o n t he P hillips PV8050, I CP s pectrometer a t R oyal H olloway a nd B edford N ew C ollege . ( Programs a re a lso a vailable f or m ajor e lement , s oil/base m etal a nd P EE a nalysis ( Walsh , B uckley & B arker, 1 981 )). T his p rogram a nalyses t he s ample f or

4 3

3 0 e lements w hich f all i nto 3 g roups .

T ema M ill S D

B urrs X S D

D ifference

w t.% A l 203

1 7.65

0 .42

1 6.75

0 .87

5 .1

F e 2O3

9 .33

0 .19

8 .63

0 .37

7 .5

M gO

1 .99

0 .05

1 .90

0 .10

4 .5

C aO

0 .69

0 .07

0 .81

0 .10

1 7.4

N a 2O

0 .37

0 .01

0 .37

0 .01

0 .0

K20

2 .73

0 .07

2 .66

0 .11

2 .6

T iO 2

0 .98

0 .02

0 .92

0 .05

6 .1

M nO

0 .03

0 .00

0 .03

0 .00

0 .0

3 34 1 8 9 4 4 9 7 2 1 3 7 0 2 4 8 7 1 95 2 7 1 12 7 9

9 .68 0 .47 3 .29 1 .69 1 .72 0 .30 5 .90 0 .67 2 .51 4 .82 0 .67 3 .24 2 .37

3 28 1 0.47 2 3 1 .04 1 10 4 .05 4 4 3 .23 7 3 4 .23 1 2 0 .54 6 3 2 .69 2 2 1 .33 8 7 2 .84 1 88 1 2.46 2 6 1 .22 1 10 4 .81 7 6 3 .53

1 .8 2 7.0 1 7.0 1 0.2 1 .4 7 .6 1 0.0 8 .3 0 .0 3 .6 3 .7 1 .8 3 .8

F Pm B a C o C r C u L i N b N i S c S r

Z n Z r

F igure 2 . A c omparison o f t he r esults f or 1 0 c lay t ile s amples g round b y T ema m ill a nd d rilled b y t ungsten c arbide b urrs. T he m ajor e lements - a luminium, i ron, m agnesium, c alcium, s odium, p otassium , t itanium , p hosphorous a nd m anganese - a re r ecorded a s w t % o xide - A1 203 ,F e 2O3 , m (: A " C aO , N a 2O , K70 , T iO 2 , P205 a nd Mn0 - a nd t hese a re u seful a s g uides t o g eneral- c hemical p atterns . S i0 2 w as c alculated b y d ifference; S i0 2 = 1 00 - ( A1 203 + F e 203 + Mg0 + C a ( ) + N a 2 0 + K20 + P2 05 + mn0 ). H owever, m ajor e lement a nalysis b y l ithium m etaborate f usion w as a lso c arried o ut t o d etermine t he r ange o f S iO, i n b oth p ottery ( 18 s herds ) a nd c lay ( 34 s amples ). A c omparison w itf i t he S iO, v alues p roduced b y d ifference s howed a c orrelation t o w ithin 2 % f or 8 2% o f t he C olchester j , ‘ f abrics a nd 8 4% o f t he c lay s amples ( figure 3 ).

Z :,

T he t race e lements B a, C o, C u , C r, L i, Mo, Nb, N i, S c, S r, V , Z n, Y a re u seful i n d istinguishing b etween s amples t hat s how

4 4

s imilarities i n t he m ajor e lement c hemistry . T hese t race e lements w ere r ecorded a s p pm , u g/g. S even o f t he r are e arth e lements L a , C e , N d, S m , F u , D v , Y b c an a lso b e u sed f or d iagnostic p urposes i n t he s ame w ay a s t he t race e lements , a nd t hey w ere a lso r ecorded a s p pm , u g/g . T he p atterns s hown b y t hese e lements ( figure 4 ) w ere v ery s imilar t o t hose o btained u sing t he i one xchange R .E .E . c oncentration m ethods ( Walsh e t a l, 1 981) a nd i t w as t herefore f elt t hat a dequate i nformation o n t he c oncentration o f t he r are e arth e lements i n t he p ottery c ould b e o btained u sing t hese d ata a lone. C OLCHESTER P UTrERY

3 43 3 73 3 75 4 12 4 63 4 66 4 82 4 99 4 99P 5 03 5 09 5 16

A 4 5.77 7 2.74 7 5.05 7 3.82 5 7.48 6 3.88 5 9.75 5 5.10 5 3.69 6 3.00 5 5.29 4 8.45

B 9 .25 2 .50 1 .38 4 .36 6 .27 1 .87 4 .69 4 .39 4 .36 6 .93 8 .76 8 .63

C 4 6.02 7 2.76 7 6.82 7 2.80 5 5.17 6 2.89 6 2.07 5 5.31 5 5.31 6 2.17 5 6.41 4 7.81

D 0 .26 0 .03 1 .78 1 .02 2 .31 0 .99 2 .32 0 .21 1 .62 0 .83 1 .13 0 .64

L ONDON C LAY

7 34 7 50 7 72 7 90 8 03 8 24 8 39 8 51 1 095 1 099 2 478 2 580

A 6 6.85 5 9.66 5 5.39 5 3.66 5 0.16 5 0.70 5 6.80 6 0.95 6 5.89 4 8.65 5 4.21 8 2.97

B 6 .93 9 .10 9 .87 1 1.07 1 1.88 1 2.30 1 0.02 1 0.30 7 .50 1 3.73 1 1.60 4 .81

C 6 7.02 6 0.07 5 7.74 5 0.95 5 0.26 4 9.81 5 5.92 6 1.03 6 6.87 4 9.05 5 4.23 8 2.92

D 0 .18 0 .41 2 .35 2 .71 0 .35 0 .89 0 .88 0 .08 0 .98 0 .40 0 .03 0 .05

F igure 3 . C omparative d etermination o f S iO 2 b y l ithium m etaborate f usion a nd t races P E p reparation m ethods . A = S iO 2 b y L iB0 2 f usion ; B = l oss o n i gnition ; C = S iO 2 b y d ifference u sing T races P E p reparation ; D = %d ifference i n S iO 2 b etween A a nd C

5 25

L a C e N d S m E u D y Y b Y

A 2 7 5 3 2 5 4 .6 1 .0 2 .9 1 .3 2 1

B 16 3 0 1 3 2 .60 0 .50 2 .04 1 .18 2 1

5 28 A 3A 7 0 3 5 5 .9 1 .4 3 .9 1 .9 2 6

B 2I 4 4 1 9 3 .70 0 .80 2 .90 6 0 1 6

4 64 A 3 J7 1 3 5 6 .9 1 .5 4 .1 2 .6 2 6

4 65 P

2 1 7

3 9 1 6 3 .10 0 .62 2 .36 1 .32 1 3

A

3 1 7

5 4 2 2 2 .9 0 .6 1 .2 0 .9 8

4 38 B

1 7

2 9 1 1 1 .80 0 .35 1 .45 0 .99 8

A

g1 92 1 03 1 7.3 4 .0 1 1.1 4 .1 8 3

B 4-4 , 9 5 4 6 8 .80 1 .92 6 .30 2 .89 3 8

F igure 4 . D etermination o f t he r are e arth e lement c oncentration ( T. 4 x0 i n f ive s amples b y A =T racesRE p reparation ( sample w eight 0 .5 a ) a nd B = i on e xchange c oncentration ( half s ample w eight 0 .25 g )

A nalysis o f m ortar j a I n s ampling t he m ortaria, t he m ain t ype o f p ottery f ound a t C olchester, w e a re l ooking a t p ots o f a s tandard p attern a nd w idespread u sage ; t he R oman e quivalent o f t he f ood p rocessor ( figure 1 4 ). E xamples h ave b een

4 5

f ound a s f ar n orth a s t he A ntonine W all i n S cotland, a nd s ome o f t hese h ave t he s ame n ame-stamps a s t he m ortaria e xcavated a t C olchester . T his w ide d istribution o f s imilar m aterial p oses s ome i nteresting Q uestions w hich multi-element a nalysis o n t he I CP s pectrometer c an h elp t o a nswer. A mongst t he Q uestions a re - a re a ll t he m ortaria f ound a t C olchester o f C olchester m anufacture, a nd i s t here a p attern w hich d istinguishes t he C olchester m ortaria c hemically? T here a re c lear d ifferences i n t he m ajor e lement p atterns o f t he m ortaria a ssigned b y o ne o f t he a uthors ( R .P .S ) a nd K ay H artley ( a m ortaria s pecialist a t L eeds ) t o s ources a t Verulamium, P as d e C alais a nd H adrian 's W all ( figure 5 ). T his i s p articularly n oticeable i n t he A l 2O3 a nd C aO c ontents . M ORTARI A

M ORTARI A

Co t vV e r

Co l vP dc

1 8 1 6 1 4 1 2 1 0

• T D ‘

8 6

2-

A l2O3

F eZ03

1410

C SO

H as°

6 20

0 Co l . mean

T iO2

P20 ,

1 . 4n0 + 5 63

0 Co l . mean

+ 5 63

N I ORTARI A

M ORTARI A

Co l vH ad . wa l l 2

Co lches ter v H ad . wa l l 1

2 8

2 8

2 6

2 6

2 4

2 4

2 2

2 2

2 0

2 0

1 8

1 8

1 6

1 6

1 4

1 4

1 2

1 2

1 0

1 0

8 6

6

4

4

2

2

8 1 203

F e 203

1410

C SO

N i : 20

0 Co l . g roan

620

T i0 12

P: 03

0 A 1 20,

1 . 19n0

+ F e20

A lgO

C a0

N a 20

0 Co l . mean

+ 458

6 ,0

1.1 0,

P20 ,

A ln0

+ 468

F igure 5 . D ifferences i n m ajor e lement p atterns b etween m ortaria f ound i n C olchester . C ol = C olchester; V er = V erulamium ; P dC = P as d e C alais ; H ad. w all = H adrian 's W all O f t he 1 70 m ortaria s ampled, 1 8 w ere e xcavated a t H adrian 's M all. C hemical a nalysis c learly d ivided t hese e ighteen i nto 2 d istinct g roups ( figure 6 ) . O ne g roup o f 9b elong t ypologically t o C olchester, b ut t he r emainder s how c lear d ifferences i n F e 03 ,C CaO 0 ,Na 2O , L i a nd V c ontent a nd h ave a n Al203 n early d ouble t hat o t t he C olchester t ype m aterial. T wo o f t he ' Colchester ' t ype m ortaria e xcavated a t H adrian 's M all w ere n ame-stamped " P AAPTINUS" a nd t heir c hemical a nalysis i s c losely c omparable w ith t he a nalyses o f m ortaria w ith t he s ame n ame-stamp f ound i n C olchester ( figures 6 & 7 ).

4 6

C olchester M EAN

M IN

Ha i . T1 1

M AX

C OLC

O THER

V erula r r t iu n M EAN

M IN

M artinus

MX

5 64

H AD . 1 A ALL

O D LC

w t . % S i0 2 6 0 .17 5 3 .13 6 7 .56

6 2 .87 6 6.99

7 5 .59 7 1 .33 7 9 .87

8 1.42

5 7 .88 5 9 .11

5 9.67

A 1 203 1 3 .06

9 .12 1 6 .74

1 2 .73 2 5 .09

1 8 .71 1 5 .85 2 2 .55

1 3 .31

1 3 .90 1 3 .52

1 3 .52

F e 203

5 .00

3 .67

6 .43

4 .93

2 .92

2 .56

1 .60

3 .31

1 .94

4 .95

4 .62

4 .92

MO

1 .20

0 .75

1 .68

0 .99

0 .79

0 .51

0 .36

0 .70

0 .48

1 .16

1 .16

1 .38

C a0

1 5 .90

8 .59 2 5 .94

1 4 .07

0 .59

0 .64

0 .45

1 .04

0 .45

1 6 .87 1 6 .97

1 6 .29

N a20

0 .52

0 .20

1 .33

0 .63

0 .26

0 .15

0 .08

0 .28

0 .29

0 .38

0 .43

1 .01

K20

1 .83

0 .76

2 .82

1 .57

2 .11

0 .82

0 .24

1 .37

1 .43

2 .06

1 .95

1 .72

T iO 2

0 .65

0 .43

0 .80

0 .64

1 .02

0 .83

0 .62

1 .05

0 .47

0 .68

0 .71

0 .72

P05

1 .56

0 .25

7 .76

1 .40

0 .20

0 .18

0 .06

0 .64

0 .20

1 .93

1 .28

0 .68

M n0

0 .10

0 .05

0 .30

0 .17

0 .04

0 .01

0 .01

0 .03

0 .01

0 .19

0 .25

0 .09

3 00 1 349 5 1 8 2 6 2 4 2 7 1 22 3 8 8 6 2 1 4 1 2 6 8 5 8 1 5 3 2 6 4 9 1 7 2 44 7 28 4 5 1 33 1 9 3 3 5 6 1 94 4 7 1 56

6 27 7 1 1 4 7 4 4 8 3 3 5 6 1 2 4 5 1 3 3 84 7 7 2 7 9 8 9 3

6 19 6 7 1 6 1 32 3 4 3 7 1 68 1 2 4 6 2 3 8 1 1 23 1 2 5 5 4 5

2 23 8 6 1 4 1 24 2 8 4 4 3 2 1 4 3 0 1 5 7 4 8 3 2 9 4 5 6 3

1 37 4 5 1 1 7 5 1 1 2 8 2 4 1 1 2 1 1 1 4 6 5 6 1 1 2 6 5 0

3 65 1 96 1 9 1 63 5 2 8 8 4 1 1 9 3 9 1 9 1 14 1 17 9 3 6 9 7 8

3 18 5 7 1 5 7 7 1 9 3 1 2 5 1 0 2 4 1 0 1 06 4 8 1 4 6 2 4 0

5 22 7 4 1 3 7 1 5 1 3 3 6 9 1 4 3 7 1 5 5 28 6 6 2 9 1 25 9 0

7 00 7 4 1 3 6 0 5 1 3 3 6 9 1 3 4 2 1 3 5 07 4 9 2 9 9 9 9 4

4 22 8 2 1 2 8 5 5 1 3 6 6 8 1 5 4 7 1 3 4 01 9 6 3 0 7 8 1 39

B a C e C o C r C u L a L i N b N i S c S r V Z n Z r

5 42 6 9 1 4 8 7 5 3 3 2 5 9 1 1 4 6 1 3 4 34 8 7 2 7 9 4 8 0

F igure 6 . Analyses o f m ortaria f ound i n C olchester a nd a t H adrian 's W all . C olchester ( MEAN, M IN , M AX ) =m ean a nd r ange f or m ortaria f ound i n a nd t ypologically a ssigned t o C olchester ; H adAeall = m ortaria f ound o n H adrian 's W all ( COLC = c hemically o f C olchester t ype, O THER = c hemically d istinct f rom C olchester ); V E milamium ( MEAN , M IN, M AX ) = m ean a nd r ange f or m ortaria f ound i n C olchester a nd t ypologically a ssigned t o V erulamium ; 5 64 s ee t ext ; Martinus = m ortaria n ame s tamped ' Martinus ' ( HAD W ALL = e xcavated a t H adrian 's W all, C OLC = e xcavated a t C olchester)

A g roup o f 1 9 m ortaria f ound i n C olchester s hows a n oticeably

4 7

d ifferent c hemical p attern ( figure 6 ; V erulamium ) f rom t hose d iscussed a bove . S orted b y c hemistry a lone, a nd p articularly o n t he b asis o f t heir A 1 203 , C aO a nd K20 c ontent , t hese a rtefacts a ppear t o c ome f rom V erulamium , t he p rovenance s uggested a rchaeologically . H owever, o ne o ther s herd ( no 5 64) h ad b een a ssigned t o Verulamium o n t he b asis o f t ypology b ut i t d id n ot f all i nto t he s ame g roup c hemically . L ooking a t t he r ange f or e ach e lement ( figure 6 ) 9e lements, i ncluding 4 m ajor o nes , f all o utside t he r ange f or t he V erulamium m aterial a nd 4 e lements ( 2 m ajor) a re a t t he e xtreme l ower e nd o f t he r ange. ( However, i f t he g roup h ad b een b ased o n a l arger n umber o f s amples i t i s a lways p ossible t he r ange m ight h ave j ust c overed t his s herd a s w ell ). As f ar a s t he m ortaria a ssigned t o C olchester a re c oncerned, a ll s how a h igh C aO c ontent, a ll g reater t han 9 % ( figure 6 ). T hose f rom V erulamium a nd H adrian 's W all t hat w ere n ot a ssigned t o C olchester s how v ery l ow C aO , t ypically l ess t han 1 %, w ith a h igher A l 2O3 o f m ore t han 1 8% ( figure 6 ). Also, t he mortaria a ssigned t o Colchester o n a rchaeological g rounds s how a m uch w ider e lemental r ange t han t hose f rom e ither Verulamium o r H adrian 's W all. T his m eans t hat i t m ay b e p ossible t o s ubdivide t he C olchester m ortaria i nto s ubgroups c hemically a s w ell a s t ypologically . I t d oes a ppear f rom t he w ork t o d ate t hat m ortaria f rom e lsewhere a re f ound i n C olchester, a nd t hat t hey d o s how p atterns w hich d istinguish t hem f rom m aterial a ssumed t o b e m ade i n C olchester. Another q uestion c oncerns t he p rovenance o f m ortaria f ound i n l ocalities o ther t han C olchester. A s a lready m entioned, 9 o f t he 1 8 m ortaria e xcavated o n H adrian 's W all s how a c hemical c omposition c omparable t o t hat o f m aterial f rom C olchester a nd t wo o f t hem w ere s tamped " MARTINUS" . T hese n ame-stamped o nes i n p articular p oint t o t he f act t hat m ortaria m ade i n C olchester f ound t heir w ay t o t he n orth, e ither i n l egionaries p acks o r, i n v iew o f t he f act t hat K ay H artley s uggested t hat o ne t hird o f t he m ortaria f ound i n S cotland a re o f C olchester o rigin, b y s ea u p t he e ast c oast ( Peacock, 1 982; S wan, 1 984). A nother p ossibility i s t hat p otters m ay h ave m igrated i n t he w ake o f t heir c ustomers . T his l ast p ossibility w ould m ean t hat t hey r eproduced t heir w ares u sing d ifferent c lays , a nd i t w ould b e c onfirmed i f t wo p ots c ould b e f ound t hat h ad t he s ame n ame-stamp b ut o nly o ne o f w hich h ad a c hemical c omposition t hat w as t ypically C olchester . S o f ar, t his h as n ot b een f ound . O ne o ther a rea t hat c an b e i nvestigated w ith w ell-dated m aterial l ike m ortaria i s a ny p ossible c hanges i n c omposition t hrough t ime ( figure 8 ) . T here a re s ome s mall c hanges b ut t hey s eem v ery s light s o f ar, a nd a f iner-scale s tatistical a nalysis i s n eeded t o t est t his . T he l ack o f a ny p ronounced c hange i mplies t hat t he p otters a t C olchester w ere u sing t he s ame , o r s imilar, c lay s ource t hrough t ime a nd s imilar p reparation m ethods . A nalysis o f s ource c lays T he R oman p otters c ould h ave e xploited t hree p ossible c lay s ources i n t he C olchester a rea ( figures 9 & 1 0). T he T ertiary a ge L ondon C lay f orms t he u nderlying g eology , a nd i t i s o verlain i n p laces b y

4 8

MORTAR IA Compar ison - Mart inus Co l vH ad . Wa l l 1 8 1 6 1 4 1 2 -

0 A 1 203

Mg10

F e2 10 3

Cal0

Na20

K2 I0

+ 403

C l 453

T iO 2

P 21 0 - 3

MnO

0 499

F igure 7 . A nalytical d ata f or m ortaria n ame-stamped M ARTINUS . 4 53 i s f rom H adrian 's W all; 4 99 f rom C olchester; 4 03 u nknown p rovenance.

MORTAR IA Co lches te r d if fe ren t a ges 1 8 1 6 1 4 1 2 1 0 86420 A 1 20 3

F e 2O3 1 3 4 22

MgO

0;0 + 499

N a 2O

K20

T iO 2

0 406

P 20 1 3

MnO

A 518

F igure 8 . A nalytical d ata o n m ortaria f rom C olchester, p ossibly s howing s mall d ifferences b etween p eriods . 4 22 = 5 0-90 A D ; 4 99 = 1 20-150 A D ; 4 06 = 1 60-200 A D ; 5 18 = 2 50 A D o r l ater. B rickearth a nd B oulder C lay - w hich f orm t he t wo o ther p ossible s ources - a nd a lso b y a lluvial s ands a nd g ravels . T he s ands w ould h ave f ormed a c onvenient s ource o f t emper w hen t he c lay w as b eing p repared f or p ottery ( Swan, 1 984). S ome a nalyses o f t he L ondon C lay a nd E rickearth h ave b een m ade ( figure 1 1 ), b ut t here a re d ifficulties i n t rying t o d etermine w hich s ource o f c lay t he C olchester p otters u sed . T he q uestions o f t he h omogeneity o f t he p ossible c lay s ources , p reparation m ethods u sed b y t he p otters a nd t he e ffects o f t hese o n t he c h . 2mical p attern o f t he c lay , a nd t he p ossible c hanges c aused b y t he f iring p rocess m ust b e a ddressed b efore a ttempting t o d etermine w hich s ource o f c lay w as u sed .

4 9

C RETACEOUS ( Cha lk ) E 3T ERT IARY ( London C lay ) =

F igure 9 . C olchester a rea, o utcrop o f L ondon C lay .

• CHELMSFORD

1 0m i les

B R IC-K EARTH C ] BOULDER C LAY

F igure 1 0. C olchester a rea, o utcrop o f B oulder C lay a nd B rickearth.

5 0

A w t.% S iO 2

6 5.70

7 5.96

6 0.17

A 1 203

1 7.06

1 8.48

1 3.06

F e 2O3

7 .88

2 .66

5 .00

M g0

3 .23

0 .48

1 .20

C aO

1 .40

0 .59

1 5.90

N a 2O

0 .58

0 .13

0 .52

K20

3 .08

0 .66

1 .83

T iO 2

0 .87

0 .84

0 .65

P205

0 .17

0 .18

1 .56

M n0 2

0 .04

0 .02

0 .10

3 52 7 8 2 1 1 29 9 5 3 9 9 6 1 3 7 0 2 1 1 98 1 89 3 2 1 26 1 01

2 00 1 03 1 4 1 20 2 2 5 1 3 2 1 3 •32 1 5 7 7 7 6 4 0 5 0 6 1

5 42 6 9 1 4 8 7 5 3 3 2 5 9 1 1 4 6 1 3 4 34 8 7 2 7 9 4 8 0

P Pm B a C e C o C r C u L a L i N b N i S c S r V Y Z n Z r

F igure 1 1. A nalyses o f L ondon C lay m ortaria ( C ).

V O, B rickearth ( B ) a nd C olchester

1 07 s amples f rom H adleigh B orehole i n s outheast E ssex h ave b een a nalysed . T hese c over 1 37 m , f rom t he C laygate B eds w hich i mmediately o verlie t he L ondon C lay a nd t he e ntire L ondon C lay s uccession . V ertical v ariation c an b e s een t o s ome d egree i n a ll t he m ajor e lements ( figure 1 2 ) a nd t he t race e lements L i a nd N b a lso s how v ariation . A ll t hese e lements i ncrease i n c oncentration t owards U nit C , t he c entre o f t he s uccession w here t he c lay m ineral c ontent i s h ighest . T his t rend i s a lso s een i n t he 2 6 s amples t aken f rom a c ore d rilled t hrough 1 30 m o f L ondon C lay a nd i ts o verlying C laygate R eds a t C rystal P alace . L ocal v ariation w ithin t he c lays i s, h owever, more i mportant b ecause t his c ould a ffect t he p roducts o f a ny p otters w orking i n t he i mmediate a rea . U nfortunately , i t i s , i n f act , q uite d ifficult t o s ample L ondon C lay i n

5 1

t he C olchester a rea , e specially a t t he s ites w here i t w as p robably d ug i n R oman t imes , b ecause m uch o f t he g round i s c overed b y l ater s lipped a nd m ade g round ( Whittaker, 1 889; P eacock, 1 982 ). H owever, 2 s amples h ave b een o btained f rom c onstruction b ore h oles i n t he c entre o f C olchester, a nd t hese s amples s eem t o b e, o n c hemical a s w ell a s g eological g rounds, f rom t he l ower, s andy p art o f t he s uccession ( figure 1 2 ). L arge s cale l ateral v ariation i s d ifficult t o g auge b ecause t he r elative s tratigraphic p osition o f c ores f rom d ifferent l ocalities i s u ncertain .

C laygate

F

E

D

C

B

A

B asal

1

2

w t .% A l 2 03

1 5 .75 1 7 .13 1 6 .56 1 7 .20 1 8 .40 1 7 .57 1 5 .55 1 1 .35 1 4 .71 1 5 .81

F e 2O3

8 .65

7 .53

8 .22

7 .97

8 .57

7 .90

6 .13

6 .40

5 .53

6 .07

M gO

2 .51

3 .22

3 .28

3 .45

3 .61

3 .16

2 .66

2 .04

2 .56

6 .07

C aO

1 .11

1 .46

1 .35

1 .37

1 .70

1 .01

0 .80

1 .89

1 .12

1 .08

N a 2O

0 .49

0 .52

0 .57

0 .60

0 .57

0 .63

0 .69

0 .66

0 .37

0 .36

K20

2 .79

3 .18

3 .07

3 .17

3 .19

3 .15

2 .84

2 .25

2 .50

2 .64

T iO 2

0 .81

0 .85

0 .83

0 .86

0 .89

0 .91

0 .86

0 .99

0 .92

0 .94

P205

0 .13

0 .15

0 .17

0 .19

0 .17

0 .18

0 .16

0 .17

0 .14

0 .14

M n0 2

0 .03

0 .04

0 .04

0 .04

0 .05

0 .04

0 .03

0 .03

0 .02

0 .02

7 8 1 1

9 5 1 2

9 3 1 1

9 9 1 3

1 09 1 4

9 8 1 5

7 6 1 3

4 8 1 2

6 2 1 2

7 1 1 2

L i N b

F igure 1 2 . M ean c omposition o f t he L ondon C lay u nits f rom t he H adleigh B orehole i n s outheast E ssex ( Claygate, A -F ) a nd f rom C olchester ( 1 & 2 ). P otters l evigate c lays a s p art o f t he i nitial s tages o f p ottery m anufacture . T his i s a w ashing p rocess t hat r emoves c oarser m aterial a nd, i n d oing s o, t akes o ut s and g rains a nd o ther h eavy m inerals . I n t he c ase o f L ondon C lay t his m aterial m akes u p a bout 1 0% , a nd t herefore j ts r emoval w ith h ave s ome e ffect o n t he c hemical p attern . L evigation m ay a lso a ffect t he p roportions o f t he s oluble e lements , s ome o f w hich c an d issolve o ut . P otters a lso a dd i ngredients a ccording t o t he t ype o f w are t hey a re p roducing - ' grog ', s and , s hell f ragments a nd c halk a re a ll p ossible t empers - a nd t his w ill a ffect t he f inal c hemical a nalysis ( Rhodes , 1 973 ). C halk a nd s hell f ragments , f or i nstance , w ill i ncrease t he c alcium c ontent , a nd i t i s n oticeable t hat t he C olchester c hemical s ignature h as a m uch h igher c alcium c ontent t han e ither t he H adrian 's W all o r t he V erulamium f abrics ( figure 6 ). T his i s a n i ndication o f a g ross a ddition b y t he p otters , p robably o f f ine g round c halk ( as s laked l ime ) o r s hell d ebris; a lthough r emanents o f t hese w ere n ot s een i n

5 2

t hin-section . T hese a dditions m ay h ave b een m ade t o h elp p reserve t he t he p ale c olour o f t he f abric b y i nterfering w ith t he o xidation o f t he r elatively h igh F e 20 c ontent . F or e xample , t his e levated C aO c ontent i s a lso s een i n t he W hite W ares f rom C olchester, b ut n ot i n t he d arker g rey f abric o f t he F ine G rey W ares . T herefore, a ny d irect c omparison b etween t he p ot f abric a nd t he r aw c lay m ust b e ' tempered ' w ith c aution. 2 0 s amples o f L ondon C lay f rom t he H ampton, Q ueen Mary C ollege, L ondon a nd C olchester b ore h oles h ave b een p repared t o i nvestigate t he p ossible c hanges i nduced b y l evigation ( washing ) a nd f iring . 5 0 go f s ample w as d ivided i nto t wo . O ne h alf w as o ven-dried a t 1 20 ° C f or 2 h ours t o r emove a bsorbed w ater, a nd t he o ther h alf w as m ade i nto a s uspension i n 1 50 m l o f d istilled w ater b y m echanical s haking . T he s uspension w as a llowed t o s ettle f or 2 h ours a nd t he t op 1 30 m l w as r acked o ff a nd f iltered . T he r esidue, o ven d ried a nd r ecrushed, w as d ivided . H alf w as r etained a s a l evigated s ample a nd t he r emainder w as m ixed w ith d istilled w ater a nd m ade i nto b rickettes . T hese w ere f ired a t 8 50 °C f or f our h ours i n am uffle f urnace . T he e ffects o f l evigation a nd f iring c an b e s een i n f igure 1 3 . F or l evigation, t he d ifference w as c alculated a s a p ercentage o f t he e lemental c oncentration i n t he u nlevigated s ample . T hese p ercentages w ere t hen a veraged, a nd t he m inimum a nd m aximum v alues w ere a lso r ecorded .A s imilar p rocess w as a pplied t o o ther f ired s amples w hich w ere c ompensated f or w eight l oss d uring f iring a nd c alculated b y c omparison w ith t he l evigated s ample . T he d ominant m ineral r emoved b y l evigation i s s ilica i n t he f orm o f s and . T he T races R E p rogram u sed f or a nalysis d oes n ot m easure S i a nd l evigation , t herefore , t ends t o i ncrease t he c oncentration o f e lements w hich a re m easured a nd d ecrease t he c oncentration o f t hose r emoved i n t he h eavy f raction . T his i s n oticeable i n t he c ase o f c alcium a s s mall c rystals o f g ypsum ( Ca M 4. 2H 20 ), p rominent i n c ertain h orizons o f t he b ore h oles , w ere r em oved by l evigation . T his p rocess h as l ess e ffect o n t he c hemical c omposition o f s amples w ith a h igh p ercentage o f c lays ized m aterial. T he c hanges i n c omposition o f f ired c lay ( figure 1 3 ) c an , w ith t he e xception o f y ttrium , b e e xplained b y t he d riving o ff o f v olatile c omponents ; p robably w ater a nd 0 0 2, n either o f w hich i s a nalysed f or . T his h as t he s ame e ffect a s t he r emoval o f s ilica d uring l evigation . Y ttrium 0 9 h owever s hows a c hange i n c omposition o f 1 8 .7% w hich c annot b e e xplained j ust b y w eight l oss . T his c hange m ay b e e xplained b y a c hange i n i n t he f orm o f t he e lement d uring f iring, w ith t he n ew f orm b eing m ore d ifficult t o d igest i n s ample p reparation . Y ttrium w ould t herefore a ppear t o b e d epleted i n t he f ired s ample w hen c ompared w ith t he l evigated o r u nfired m aterial . T herefore , l evigation a nd f iring c an h ave a c onsiderable e ffect o n c omposition a nd i t i s p referable w hen c arrying o ut a s tudy l ike t his t o p repare t he r aw c lays b y b oth p rocesses b efore c omparing t he c lay d ata w ith t hat f rom t he f inished p roducts . T his i s v alid a pproach i f i t i s k nown t hat t he p otters w ere l evigating t he c lay , a nd t his i nformation i s o ften a vailable f rom a rchaeologists .

5 3

A

m in

m ax

B

m in

m ax

C

m in

m ax

A l 203

5 .6

2.9 2 4.7

0 .2

4.2

6 .2

1 1.0

2.9 2 4.7

F e 2O3

4 .7

5.5 2 4.0

1 .7

2.5

8 .7

1 8.7

5.5 2 4.0

M gO

5 .0

5.7 2 6.6

0 .4

3.9

6 .7

1 7.3

5.7 2 6.6

C aO N a 20

3.7 25.6

9 .3

0 .2

3.8

7 .4

11.5 27.8

0 .0

4 .3

6.9

1 8.2

6 .0 12.0 2 3.3 0 .2 27.6

0 .0

K20

0 .6

7.8 1 2.2

1 .9

2.6

1 1.0

1 3.3

7.8 1 2.2

T iO 2

1 .6

3.5 1 0.9

0.4

6.3

7 .5

1 2.5

3.5 1 0.9

P 05 -2

3 .3 13.3 1 6.7

1 .9

6.7

8 .3

1 8.6 13.3 1 6.7

B a C e C o L a L i S c Z n

3.0 20.6 1 2.5 5 .9 4.0 1 6.4 7 .2 0 .0 2 3.5 8 .0 7.5 2 0.6 7 .8 7.0 3 6.6 8 .5 0 .0 3 1.3 2 .9 6.4 1 3.9 4 .8 5.4 1 8.8

1 .7 3.3 1 1.2 1 .7 4.2 8 .0 2.1 6.7 5 .6 1 .0 5.3 8 .1 3 .3 2.6 1 1.3 1.1 8.7 5 .0 18.7 26.7 12.2 4 .9 10.8 2 0.5

1 5.8 1.5 1 7.0 4.0 1 5.7 1 1.1 1 8.1 5 .4 2 3.1 7.0 1 9.2 0 .0 6.9 16.7 2 2.5 7 .1

2 6.6 3 0.4 3 5.3 3 1.4 3 6.6 3 1.2 0 .0 4 3.0

F igure 1 3 . T he e ffect o f l evigation a nd f iring o n t he c omposition o f L ondon C lay s amples f rom t he H ampton, C rystal P alace a nd C olchester b oreholes . A=a verage d ifference b etween l evigated a nd u nlevigated c lays; 1 3=a verage d ifference b etween f ired a nd l evigated c lays; C = t otal a verage d ifference b etween u nlevigated a nd f ired c lays. S etting u p t he d atabase B ecause t he I CP c an a nalyse f or u p t o 3 0 e lements s imultaneously i n a v ery s hort p eriod o f t ime, i t i s p ossible t o g enerate a g ood a nd w ider anging d atabase . W e h ave u sed t he L otus 1 -2-3 s preadsheet p ackage a s t he v ehicle o n w hich t o e stablish t he d atabase . I t w as c hosen b ecause o f i ts w ide a vailability , I BM c ompatibility a nd e ase o f u se . N ot o nly h ave w e d rilled 1 70 m ortaria, b ut a lso S amian, W hite a nd R ed Wares, f ine G rey W ares a nd e arly c oloured-coated w ares f rom C olchester . A ll t he c hemical d ata f or t hese s herds a re p resently a ccessible , a nd a ll c an b e c opied o nto a f loppy d isk f or o ther u sers . I n t he c ase o f t he m ortaria w e h ave b oth c hemical a nd f ull a rchaeological d ata a vailable f or o ther u sers . C hemical d ata f or t he H adleiah b orehole s amples , o ther L ondon C lays a nd B rickearths a re a lso o n d atabase a nd a ccessible f or r eference . W e t hus h ave a g rowing d atabase, a ssessible t o o ther u sers , w ho c an u se i t a s a r eference s ource f or C olchester p ottery f abric . A cknowledgments We w ould l ike t o t hank P .J . I v 1erriman, B ritish G eological S urvey ; B .Harvey , R egional E ngineering L aboratory , T hames W ater A uthority a nd S .J .Adams , Q ueen M ary C ollege , L ondon U niversity f or p roviding s ome o f

5 4

t he s amples . W e a re g rateful f or t he i nvaluable t echnical, s ecretarial a nd c artographic h elp o f J an B arker, Alison Warren, S arah Viaaers, C hristine F lood a nd C raig U ildrew, R oyal H olloway a nd R edford N ew C ollege, U niversity o f L ondon . T he i nductively-coupled p lasma s ystem o perates a s p art o f a N ERC-supported f acility , a nd w e a cknowledge N ERC a nd a lso t he i nstrument m anufacturers ( Phillips ) f or t heir f inancial s upport . T he a uthors a re g rateful t o S ERC f or t heir h elp i n f inancing t he p roject.

R EFERENCES P eacock D .P .S. ( 1982) e thnoarchaeological a pproach R hodes D .

( 1973)

Pottery i n t he L ongman, N ew Y ork

Roman

C lay a nd G lazes f or t he P otter

S wan V .G . ( 1984 ) T he C ommission, S upp .Series 5

Pottery

K ilns

o f

Roman

World,

an

P itman, L ondon B ritain

R oyal

T hompson M . & Walsh J .N . ( 1983) A H andbook o f I nductively C oupled P lasma E mission S pectrometry B lackie, G lasgow W alsh J .N ., B uckley F . & B arker J . ( 1981) T he s imultaneous d etermination o f t he r are-earth e lementS C hem . G eol. 3 3 Walsh J .N . & H owie P .A . ( 1986) R ecent d evelopments i n a nalytical m ethods : t he u se o f i nductively c oupled p lasma s ource s pectrometry i n a pplied g eology a nd g eochemistry A pp .Geochem . 1 1 61-71 W hitaker W .

( 1889)

G eology o f L ondon

5 5

M emoir G eol.Survey , L ondon

F igure 1 4. Mortaria, g ritted i nner s urface.

s howing t he p ouring s pout,

5 6

g ripping r im a nd

A �ICAL AND MINERAUX;ICAL STUDY OF

NAN'IGruM

OORCELAIN

A.M.Pollard and S.Bourner Dept. of Chemistry, University College, Cardiff CFl lXL

Nantgarw, a small village six miles north of Cardiff, produced porcela in of outstanding quality between c.1810 and 1820, although it had produced other types of pottery before this and continued to do so until the 1920s. The site was partially excavated in the 1930s, resulting in a collection of some 300 porcelain sherds, now held by the National Museum of Wales. William Billingsley went from Derby to Nantgarw in 1811, and started to make porcela in. He went briefly to the Swansea factory in 1814, returning in 1817. Two years later he removed to Coalport, taking his porcelain recipe with him. With the aid of chemical analysis by X-ray fluorescence, an attempt has been made to compare the products of Nantgarw with the published contemporary raw mater ial recipes, and to detect any changes in body compositi on before and after 1815. Compar isons have also been made between Nantgarw, Swansea and Coalport porcela in, to examine the connection between them. Particular attention has also been paid to the cause of losses during biscuit firing, thought to be as high as 70%.

57

C LAY S OURCES A ND C ORINTHIAN A MPHORAE

G .W .A.Newton, V .J.Robinson, M .Oladipo & M .R .Chandratillake, C hemistry D epartment, M anchester U niversity a nd I .K.Whitbread, A rchaeoloay D epartment, S outhampton U niversity

A bstract C orinthian a mphorae d atina f rom t he 7 th t o 3 rd c enturies B C a nd G reek c lays ( possibly u sed b y t he a ncient p otter ) h ave b een m onitored b y n eutron a ctivation a nalysis . A d atabase o f 2 2 e lement c oncentrations h as b een e stablished f or 6 0 p ottery s amples a nd 1 35 c lay s amples . T he d ata h as b een a nalysed b y a r ange o f s tatistical p rocedures , p articularly c luster a nalysis u sing Ward 's m ethod a nd t he R FLOC p rocedure . I n a ddition c omparison o f c lay a nd p ottery g roups w as c arried o ut u sing D iscriminant A nalysis . C orinthian A a nd B a mphorae w ere d istinguished c learly a s w ere e ight d ifferent c lay t ypes . F rom c omparison o f t heir c hemical c ompositions i t w ould a ppear t hat p ossible c lay s ources f or C orinthian Aa mphorae w ere Megalopolis, w hereas C orinthian P a mphorae w ere n ot a ssociated w ith a ny o f t he c lays . I ntroduction P rovenance o f a ncient p ottery b y c hemical a nalysis i s n ow a w ell e stablished t echnique ; o f t he various m ethods n eutron a ctivation a nalysis g ives r eliable d ata f or s ome t hirty t race a nd m inor e lements i n e ach s ample . T he u sual p rocedure i s t o e stablish a d atabase o f k nown s amples, t his w ould b e o f t he o rder o f t en t o t wenty s amples f or a s ingle g roup a nd tMn c ompare t his w ith u nknown s amples . I dentifying s tandard m aterial i s o ne o f t he d ifficulties o f t his t ype o f w ork . A mong t he h est r eference s amples a re k iln s ites a nd i n p articular w asters b ut f or t he t ype A a nd B C orinthian t ransport a mphorae s tudied i n t his p roject n o s uch s ources w ere available . I t w as d ecided, i n c onjunction w ith I .K . W hitbread, t o u se c lay t aken f rom a v ariety o f s ources ( some o f w hich w ere t hought t o h ave p ossibly b een u sed b y t he a ncient p otters - i .e . A etopetra a nd S olomos ) a s am eans o f t esting t he C orinthian o rigin s uggested f or t he a mphorae . F or e ach c lay s ource s everal s amples w ere t aken a t d ifferent d epths a nd a t d ifferent p oints a long t he s eam . T he r esults s hould g ive i nformation o n t he u niformity o f c lay b eds w ith r espect t o t race a nd m inor e lement c oncentrations, i n a ddition t o p roviding r eference m aterial f or t he s uite o f p ottery s amples . C lays ( usually g rey i n c olour ) w hich a re s tratified w ith l ignite w ere u sed a s a c ontrol

5 9

b ecause t hey a re c lays f rom s imilar g eological e nvironments a nd a re w ell s uited f or p ottery m anufacture ( Cardew, 1 969 p .35 ). A part f rom a mphorae , s everal o ther p ottery s amples w ere a nalysed a s d escribed b elow .

T he s amples C lay T here w ere e ight s ources , b elow .

M anchester S ample L ahpl

a s s hown o n t he m ap i n f igure 2 a nd d etailed

C lay S ite

C 22-29 C 30 C 31 C 32 C 33-42 C 43-49 C 50-55 C 56-60 C 61-68 C 77-84

A etopetra C orinth B rick F actory C orinth B rick F actory C orinth c lay h eep F ast o f S erres K ato A lepochori ( Megara ) K okkinarea M egalopolis M ouzakion P rosilio

C 86-87 C 88

S erres Q uarry 4 A crocorinth 3 rd t errace c entre M egapolis S ide o f A rgos R oad

C 89 C 90

D escription

N o . o f s amples

L acustrine R ed f abric G rey f abric B ed m aterial M iopliocene, l acustrine P liocene L acustrine S ame a s M egara P liocene, m arine m iopliocene, l acustrine a nd t errestrial ( marls )

8 1 1 1 1 0 7 6 5 8 8 2 1

1 1

F igure 1 . C lay s amples P ottery T he s amples a re d etailed i n A ppendix 1 . Type A a mphorae

T ype B a mphorae T erracotta w are P erirrhanteria

- t here w ere 1 9, 9 o f w hich w ere f rom c ontrol g roup o f t he F itch l aboratory . B ritish S chool a t A thens . - 1 0 s amples - 1 6 s amples o f v arious t ypes - 1 8 s amples ( or l outeria ).

t he

E xperimental C lay A ll

t he s amples d escribed a bove w ere t reated i n t he s ame w ay .

6 0

B ucket-

F igure 2 . M ap o f G reece s howing t he l ocation o f c lay s ites.

s ized s amples w ere o btained f rom t he s ite . About 1 k g o f t his w as t reated w ith w ater t o r emove v ery c oarse m aterial a nd t he v ery l ight f raction . T he i ntermediate s uspension w as a llowed t o d ry t o aw orking

6 1

c onsistency a nd f ormed i nto s mall t iles . T hese w ere d ried a t 1 20 ° C a nd t hen f ired i n a n e lectric f urnace a t 1 000 ° C . T he f inal t emperature w as c hosen b y e xperiment s o t hat t he p roduct w as v isually s imilar t o t he a ncient p ottery . T he i mportance o f t his p rocedure i s s hown i n F igure 3 , w here t he e rrors f or A etopetra c lay b efore a nd a fter h omogenisation a re s hown . T his p rocess w ould b e s imilar t o t hat c arried o ut b y t he a ncient p otter. A 2 00 m g s ample f or a nalysis w as d rilled f rom t he f ired t ile w ith a d iamond d rill. I t h as b een s hown t hat t his d oes n ot c ontaminate t he s ample .

A ETOPETRA C LAY ( S.D .% ) E lement

B efore

A fter

N a M g A l K C a S c T i V C r M n F e C o P b S b L a C e S m E u D y H f T h U

3 4 1 1 1 8 3 6 2 4 1 6 2 0 1 9 2 3 1 1 1 5 3 0 1 6 1 7 1 6 1 8 1 3 1 1 2 3 3 0 2 1 1 8

3 9 1 2 1 5 1 4 2 1 2 9 3 5 3 3 8 1 2 3 3 2 6 1 5 6 3 1 1

2 0%

7 .2%

A verage

F igure 3 . E ffect o f h omogenising c lay P ottery T he s urface o f t he s herd w as c leaned a nd a 2 00 m g s ample d rilled f rom t he i nterior w ith a d iamond d rill. S ome s amples w ere r efired a t 1 000 ° C , h ut s ince t he a nalytical r esults b efore a nd a fter f iring w ere t he s ame, t his w as r ecognised a s a n u nnecessary p rocedure . I rradiation a nd c ounting T hree d ifferent r egimes w ere a dopted: 1 . s hort-lived i sotopes ( Mg, A l, C a, T i, V , Mn, P a , S m, E u , U ) t en m inute i rradiation, t hirteen m inute d ecay , f our m inute c ount f or s ample 1 a nd e ighteen m inute d ecay, f our m inute c ount f or s ample 2 . ( 2

6 2

s amples i rradiated t oaether t o i mprove t hroughput ); 2 . i ntermediate-lived i sotopes ( Na , K , t wo h our d ecay , t wenty m inute c ount ;

M n , D y )

t en m inute i rradiation,

3 . l ong-lived i sotopes ( Sc, C r, F e, C o, C a, A s , P b, S b, C s, L a, C e, S m, Y b, L u, H f, T a, P a ), s even h our i rradiation, t en d ay d ecay , t wo h our c ount . R esults T he r esults f or 1 75 s amples a nd t he 2 2 e lements t hat o ccurred i n e very s ample a re l isted i n A ppendix 2 . D iscussion H ierarchical c lustering u sing W ard 's m ethod a nd P ELOC f rom t he C LUSTAN p ackage t ogether w ith d iscriminant a nalysis f rom t he S PSS s uite o f p rogrammes w ere u sed t o i dentify g roupings i n t he s amples . T he Ward d endrogram f or a ll t he c lay s amples i s s hown i n f igure 5 . I t i s c lear t hat t he c lays a re b reaking i nto c hemical g roups b ased o n t heir o rigin a lthough t his g rouping i s n ot p erfect . T he i mportance o f c orrelations w as d iscussed i n a nother p aper a t t he c onference . I t i s i mportant t o c heck i f c orrelations b etween e lement c oncentrations d o e xist a nd , i f t hey d o , t hey m ust b e c orrected f or u sing t he p rinciple c omponent a xes, o therwise e rroneous r esults w ill b e o btained . C orrelations f or a ll t he c lay s amples a re s hown i n f igure 6 ; i t c an b e s een t hat t here a re a l arge n umber o f v alues a round 0 .7 o r l arger . I t i s a ssumed t hat t hese l arge v alues a re s ignificant a nd t hat c orrections a re r equired . W hen t he Ward a nalysis i s r un o n t he c orrected d ata a much b etter p icture e volves, a s s een i n f igure 7 , a nd t his i s p erfect w hen t he t wo o utliers a re r emoved ( figure 8 ) . S ample N ame P ot ( 1 BA mphorae ) P ot ( all P A mphorae ) F ineware A etopetra A etopetra E ast o f S erres E ast o f S erres M egalopolis M ouzakion K okkinarea K ato A lepochori S olomos P rosilio

N o. o f S amples

A verage S .D .(% )

3 1 0 2 2 4(* ) 8N 2 4(* ) 1 0 N 5 (\ ) 8N 6 (\ )

6 .2 1 6.0 9 .3 7 .2 6 .3 6 .3 1 5 .2 1 1 .5 1 3 .2 1 3 .5

7N 8 (\ ) 8 (\ )

1 4 .4 1 4 .2 3 6 .9

( * )r epeat a nalyses o n o ne h omogenised s ample f rom t he s ite ; a nalysis o f t he n d ifferent s amples f rom o ne s ite . F igure 4 . A verage s tandard d eviation f or c lays a nd a p ot.

6 3

1 ZZ ° NI P SP /13

* C22 $ C76 * C27 * C23 * C26 * C24 $ C72 $ C74 * C25 $ C73 $ C69 $ C70 $ C75 % C62 % C66 % C67 % C63 % C68 % C64 $ C7 1 * C29 % C6 1 @ C43 @ C44 @ C46 X C54 @ C45 @ C47 @ C49 @ C48 X C50 X C5 1 X C53 X C52 X C55 * C28 0 083 0 084 0 077 0 078 0 079 0 080 08 1 0 082 + C33 + C38 + C36 + C37 + C39 + C40 + C41 + C34 + C42 + C35 ? C56 ? C57 ? C60 ? C58 ? C59 % C65

F igure 5 . W ard d endrogram o f c lay s amples

6 4

CO

C

•

4 4

•

r-

r 1

E

▪ 0,

. r0,

CO

CO 0,

0,

rn

f l

L ▪ C %

0 M

C r % I f 1

C i

C . 2

=

M ? C-

M = CO

CO In CO

= ' 0

c r s CO 0

c r s 0, 0

s .o

. -

C .) CO

-

N -

L C ,

L .

U

M „ c , . -

•

I 1 , 3 . %

. .-

,

. -

. .

M . . -

. . . -

0

N

00

0

co r e l 0

N M

•

• M-

O In . -

rn co 0

, c ) 0

•

N 0 . 1

1

1

? , ._ 0

. in c-

. . NI N

40 as • •

0 i t % c m

co rn N

L4 ' NN

I

1

1

I

L

rn

I sm

= c r s

. .O rn

N rn

N 0

I-in

M

N

• • • .

0

N

I

= Nco

C c _ )

r0 rn

CO

. r --

CT / 4 1 0 co

M . .0 co

I l l r . . .

0 c r ,

40 / 1

I

t r ,

1

4
Im PIOXJCl'S : .ANALYSIS AND INTERPRETATICN

M. Fabrizi 10 1, Woodland Way, Winchrrore Hill, London N21 3PY There has been a continuous interest in the corrosion of archaeological copper alloys for rrore than two.hundred years, and it is imfX)rtant to understand the evolution of ideas on the nature of corrosion processes, and to appreciate the impact of the various analytical techniques. '1'he eighteenth century

One of the ear 1 iest accounts of ancient corrosion products was published by Sage, in France, in 1779. His article described cuprite crystals on two different objects made of gilded copper. He.referred to cupr i te as 1 a mine r ouge de cui v re and pro ved that the archaeological crystals were in all.ways identical with those of the red copper ore. He also reported the presence of malachite and azurite as corrosion products on buried objects, and there were other crystals that he noted but could not identify. In this early work the canpounds formed by corrosion processes were considered as minerals, and this idea persisted. 11

11,

Sage had_no modern knowledge of oxygen, because Lavoisier's memoir "On Combustion in General", describing combustion supported by oxygen, only appeared in 1780. Therefore, Sage subscribed to the Theory of Phlogiston, in which removing phlogiston was e quivalent to adding oxygen and .adding phl ogisto n was- the same as removing oxygen (Partington, 1957). Sage (1779) said that cupri te (.red copper oxide) was the product of copper metal with its phlogiston removed ' ••• la mine rouge de cui vre,. n'est qu'une al t�ration du cui vre natif, ou ce m€tal pri_v� d'une portion de son phlogistique • • • ' and, with the scientific knowledge of the period, he could not have described it in any other way; particularly as he was sure that only copper and phlogiston/oxygen were involved in the reaction. His conclusions were based on destructive chemical tests, and examination using a lens, and he was at a great disadvantage regarding the methods and equipment available to him at that time. 'l'he nineteenth century

The role of chlorides and electrochemical phenomena in corrosion were only really beginning to be understood by the 1820s, when Humphry Davy (1824/5) published an article about the corrosion of copper sheeting on ships in sea water. His research showed that protection could be o btain ed by attaching relative ly. sma l l qu antities of mo re electropositive metals like zinc and iron to the copper plates, and he therefore initiated cathodic protection. In 1826, his brother John Davy made a report on his own work with 295

c orroded a rchaeological m aterials . H e t oo d escribed t he c orrosion p rocess a s a " mineralising p rocess" , a nd s eemed t o s hare S age 's ( 1779 ) e arlier v iew . D avy r eported o n ab ronze h elmet f ound i n s hallow s ea w ater n ear C orfu , a nd d escribed t he c orrosion p roducts a s c onsisting o f c uprite a nd c opper c rystals , t in o xide a nd a ' green r ust ' c omposed o f .. t he c arbonate a nd s ubmuriate o f c opper . . . " ( Davy , 1 826 ). T his i s o ne o f t he e arliest r eferences t o t he f ormation o f c hlorides i n c orrosion p roducts b ecause h ydrochloric a cid w as c alled m uriatic a cid a t t hat t ime, a nd t herefore t he ' submuriate o f c opper ' w as a b asic c opper c hloride c ompound . D avy a lso a nalysed t he u naltered m etal, a n 1 8 .5 % t in/copper a lloy , a nd h e e xamined s everal o ther a rchaeological o b jects i n t erms o f t heir c omposition a nd c orrosion p roducts . J ohn D avy a lso t ried t o r elate t he a ppearance o f c orroded c oins t o t he c orrosion c ompounds o n t heir s urfaces b ut , a lthough t here w ere s ome c orrelations , h is a pproach w as s omewhat n aive . H e w as o bviously l imited b y h is p erception o f t he t ypes o f c opper c ompounds t hat c ould b e p resent , a nd h is i deas o n t he c orrosion r eactions t hat c ould o ccur. N evertheless , h e w as a ware t hat m ore t han o ne k ind o f c opper o xide c ould e xist , a nd h is a rticle ( Davy , 1 826 ) w as p ossibly t he f irst t o i dentify t he b lack c opper o xide ( tenorite ) a s a c ompound t hat c ould b e p resent i n c orroded o bjects . H owever, h e d id n ot r ealise t hat t his w as a n i ndication t hat t he o bjects h ad b een h eated, a nd even h is i dentification o f t he b lack c ompounds a s o xides m ight h ave b een i ncorrect , b ecause t here i s a lways t he p ossibility t hat t hey w ere s ulphides . L ike S age b efore h im , J ohn D avy w as f ully a ware t hat d ifferent c ombinations o f c orrosion p roducts c ould b e f ound o n as ingle p iece o f m etal. H e a lso m ade i t q uite c lear t hat h e u nderstood t hat c orroded a lloys p roduce c ompounds t hat a re s omewhat r epresentative o f t heir c onstituent m etals . T hus, a t in b ronze w as r ecognised t o b e e ncrusted w ith b oth t in a nd c opper c ompounds , a nd i t w as r ealised t hat e ven a c ompletely m ineralised m etal c ould s till g ive i nformation o n i ts f ormer n ature . J ohn D avy d iscussed p ossible c orrosion p rocesses, a nd g ave t he o pinion t hat e lectrochemical p henomena w ere i nvolved ; av ery s imilar a pproach t o t hat o f h is b rother i n h is w ork o n t he c opper-clad s hips i n s ea w ater . T his n ineteenth c entury i nterest i n c orrosion p henomena w as n ot s olely f or a bstract s cientific p urposes . T here w as a lso a d irect, p ractical a pplication b ecause t he e xamination o f p atinas w as t hought t o b e a w ay o f d etermining t he a ntiquity a nd a uthenticity o f m etal o bjects . D avy , f or i nstance, s aid t hat t he c omposition a nd s tructure o f n atural p atinas c ould n ot b e r eproduced b y a rtificial p rocesses , a nd h e s uggested c hemical t ests , a nd m ethods i nvolving t he u se o f a l ens , t o d etect m odern c opies . T he q uestions o f a ntiquity a nd a uthenticity a re s till a ddressed b y s ome w riters , b ut c onsideration o f t he i dentity a nd s tability o f c orrosion c ompounds i s a lso a n i mportant a spect b ecause o f t he i mplications f or t he s afe s torage a nd d isplay o f a rtefacts . T he a spect o f a ntiquity b ecomes u nimportant i f t he o bject t urns i nto a p ile o f g reen c rystals . I n O ctober 1 856, C hevreul p ublished a n a rticle a bout E gyptian b ronzes w hich h ad c ome t o t he L ouvre f rom r ecent e xcavations b y M arlet te . P robably t he m ost r eliable i nformation c omes f rom t he s tudy

2 96

of recently excavated material, and so these were ideal subjects for his experiments. The statuettes had been found buried in sand, in the foundations of a temple. They were covered in a green layer of variable thickness which, in turn, overlay reddish material. Sometimes a residual metallic core was also present. Sand and other material from the burial environment had been deposited on the exteriors of the objects, forming a type of breccia. Some of the statuettes were hollow castings, and these had some white material inside. This was shown in one case to be a mixture of sodium chloride and at least two calcium salts, and the sodium chloride, at least, would have promoted corrosion. • The green material was examined separately and found to be " • • du cuivre oxychlorure au Ptrou". This was atacarr.ite, and there was no doubt about the role of chlorides in its formation. Atacamite is one of the common products of accelerated chloride corrosion in copper alloys, and this reaction is now generally known as 'bronze disease'. Some blue copper carbonate formed part of the outer layer examined by Chevreul, and some cassiterite was also mixed with it. Th1s tin compound had not been noticed on the surface during a preliminary visual examination, and its· presence was only revealed through chemical analysis. The red layers were mostly mixtures of cuprite and cassiterite (tin dioxide), but Chevreul's work again proved that some harmful chlorides were present within these apparently innocent oxides. The uncorroded wetal was also examined, but the results were not given in any detail. Chevreul then reported on an attempt to "revive" a completely corroded bronze. He took a completely· mineralised statue of Anubis and reduced it in a stream of heated hydrogen gas. The experiment was a success, and he displayed the restored object, together with the water and hydrochloric acid that had formed during the reaction. Further, he reported that chlorides, soluble in water, had been found in the sand in which the statue had been buried, and he said that there seemed no doubt that air, salty water and carbonic acid were the agents responsible for the corrosion that he had observed (and tried to reverse) . In N ovember 1856, Chevreul published another report that included further discussion on the red layer found on the statues. He believed -that the most likely reason for the existence of substantial aroounts of chlorides within the red material was that " • • • protochlorure de cuivre • • • " was present. This was CuCl, now often referred to as nantokite when it occurs as a corrosion product, and this may be the first time that its nature as a corrosion product was considered. Chevreul also examined some of the red samples under the microscope, and saw that there were different types of crystals occurring in material that had seemed fairly homogeneous to the naked eye. Detailed crystallographic information was not available to him, so he was uncertain which crystals corresponded to the individual compounds that he had already identified as being present . However, his use of a microscope was a great step forward. Data on crystallography slowly started to accumulate, and Daubr�e for instance, described and identified various kinds of crystalline sulphides. This was just one of his many articles on the (18.75),

297

formation of copper compounds and other crystals in hot springs. In this particular paper he first described the conditions at the spring and the material that had been preserved. This included a variety of different substances, including plant remains, and also nearly five thousand Roman coins that had been thrown in as offerings. 4,600 of the coins were of either copper or bronze. Below the level where rrost of the coins had been found was a layer formed of stone fragments, mostly sandstone, that were more or less cemented together with crystalline substances that had a metallic lustre. The materials were sarrpled, and sent to the Minister of Public Works, and then Daubr�e was given them to examine and he was helped by Mr Richard of the School of Mines. The compounds within the stone agglomeration appeared to be minerals, but it was specifically pointed out by Daubr�e that they could.not be of geological origin because, as well as cementing the stones together, they also coated some of the coins. Several copper corrosion products were identified and described in detail. Very full information in particular was given on the crystal form of the compounds and a microscope had clearly been used in the work. This information on crystal form was backed up with wet chemical analyses, each of which would have required several grams of sample material. These analyses were destructive and unrepeatable. Daubree i denti fied chalcocite, covellite, chalcopyrite, bornite and tetrahedrite. The first two of these contained only copper and sulphur, and the next two only copper, sulphur and iron, but a full analysis of the tetrahedrite showed that it contained large amounts of antimony, and traces of arsenic, as well as copper and sulphur. The hot spring where the objects had been found was investigated but the water contained no antirrony. However, as chemical analysis of the coins showed that they did contain .antimony, it was concluded that the tetrahedrite must have derived from corrosion of metal, even though none of the coins contained more than 1% antimony. There were no iron objects present, and only a little iron in the coins, and so it was deduced that the iron in the chalcopyrite and bornite must have come largely from the corrosion environment. A sulphate reduction mechanism was thought to be responsible for the production of the hydrogen sulphide gas that was noted from time to time in the atrrosphere around the spring, and it was supposed that this sulphide was also involved in the production of the compounds found on the copper alloys and between the stone fragments. The presence of some chlorides in the water of the spring was shown to have had no obvious effect on the metals. This work illustrates that, even with the facilities then available, if masses of material had corroded together in conditions favourable for crystallisation there was a good chance that the individual corrosion products could be identified. However, small surface deposits on individual objects were less easy to investigate. Even the identification of a well-characterised material like malachite proved difficult before the regular use of X-ray dif fraction, as pointed out by Lewin and Alexander (1967/8) " • • • malachite could be identified as such only if it were present (a) in a large enough quantity so that the 298

s toichiometric p roportions o f c opper, h ydroxide a nd c arbonate c ould b e d etermined b y c lassical w et c hemistry , a nd ( b ) i n a s ufficiently w ell-crystallised f orm s o t hat i ts o ptical c onstants c ould b e d etermined b y m ethods o f p etrographic a nalysis t hrough p olarization m icroscopy ( substantially f ully d eveloped b y 1 860-70 )." I t i s v ery r are f or b oth t hese c riteria t o b e s atisfied w hen d ealing w ith a rchaeological m alachite . A s o nly a f ew c ompounds h ad y et b een p ositively i dentified o n t he s urface o f c opper-based o bjects, t here w as a t endency t o a ssume t hat a ll g reen d eposits m ust b e m alachite a nd s imple t ests o ften m erely c onfirmed t his a ssumption . T hus, d ilute h ydrochloric a cid w as o ften d ropped o n t he s urface t o c onfirm t he p resence o f c arbonates, b ut , o bviously , t his w ould o nly c onfirm t he p resence o f ac arbonate , a nd n ot n ecessarily m alachite . C alcite, a zurite a nd c halconatronite, f or e xample , a re a ll c ompounds t hat o ccur o n t he s urface o f c orroded c opper o bjects . T hese , a nd m ixtures o f c arbonates , w ould a ll r eact s imilarly t o t he a pplication o f d ilute a cid . T herefore, m any e arly r eports c ontain i dentifications t hat m ust b e r egarded a s s uspect, a s t hese i dentifications w ere v ery m uch i nfluenced b y t he t echniques a vailable , t he w ay t he s amples w ere t aken a nd p erceptions a bout t he p ossible c ompounds t hat c ould b e p resent . T hus, a fter t he d evelopment o f p olarization m icroscopy i n t he 1 860s, t here w ere n o s ignificant b reakthroughs i n m ineral i dentification f or a round f ifty y ears, a lthough t here w ere s ome a dvances i n t he u nderstanding o f c orrosion p rocesses . F or e xample, B erthelot ( 189A ) s uggested a c yclic m echanism f or l ong-term c orrosion i nvolving s mall q uantities o f s odium c hloride , a nd h e w as o ne o f t he f irst t o u se t hermodynamics i n h is s earch f or a n e xplanation o f c orrosion r eactions . T he t wentieth c entury T he m ost i mportant w ork f or t he s tudy o f c orrosion p roducts e merged i n 1 913 w hen t he B raggs f irst a pplied X -ray d iffraction a s a t ool f or t he i dentification o f c rystalline p hases , a lthough , o f c ourse , t his d id n ot b ecome a r outine a nalytical t echnique u ntil s everal d ecades l ater. H owever, i nteresting r esults w ere o btained e ven a t t his e arly s tage . A n a nalysis o f c alcite b y X -rays w as p ublished i n 1 914 ( Bragg & C laringbull, 1 965 ), a nd t he a nalysis o f c uprite ( red c opper o xide ) w as p ublished s oon a fter t his ( Bragg & B ragg, 1 916 ). G eological a nd c hemical a pplications w ere r eadily a pparent , a nd a g rowing s tream o f p ublications b egan t o a ppear . F or e xample , W eiser a nd M illigan ( 1932 ) r eported o n t he d ehydration o f h ydrous s tannic o xide a t d efinite t emperatures . T hey u sed X -ray d iffraction t echniques t o s how t hat n o d efinite h ydrates w ere f ormed , a nd t hat t he p roducts w ere a ll s tannic o xide , o f v arying p article s ize , a nd w ith v arying a mounts o f a bsorbed w ater . T his s ort o f w ork h ad i mportant i mplications f or t he s tudy o f t he s tability o f c ompounds a nd t heir t ransfo r mations . C haracterisation o f g roups o f c ompounds h aving v ery s imilar c hemical c ompositions c ould n ow b e a chieved . At l east e ight c opper c ompounds c ontaining s ulphates c an b e f ormed i n c orrosion e nvironments ,

2 99

a nd t hese c ould n ow b e d istinguished w ith a c ertain d egree o f c onfidence . I n 1 939, P alache g ave a f ull a ccount o f a ntlerite a s a n i ndividual s pecies , b acked u p b y X -ray s tudies b y R ichmond w hich w ere a ppended t o t he a rticle . S ulphates a re t he m ost c ommon c orrosion p roducts o n o utdoor i tems s uch a s s culpture a nd d oors o f c opper a lloys . W hen t his t ype o f c ompound i s i dentified t he c onservator w ill b e a ble t o p rovide a ppropriate t reatment f or t he o bject . A lso , s ome c ompounds o nly f orm u nder v ery s pecific c ircumstances, a nd t herefore t heir p resence c an g ive s ome i nformation o n b urial e nvironment a nd p rovenance i f t hese a re n ot a lready k nown . H urlbut ( 1942 ) u rged g eologists t o i nclude X -ray d ata w henever t hey p ublished i nformation a bout a n ew m ineral s pecies . R ecently , a s eries o f E gyptian c orrosion s amples w ere a nalysed b y X -ray d iffraction . T heir c rystal s tructures w ere s hown t o b e i dentical w ith t he m ineral s ampleite, N aCaCu 5 ( PO 4)4C 1.5H 20 ( Fabrizi & S cott , 1 987 ). D ata f rom t he J CPDS w ere c ombined w ith t he c hemical a nd c rystal i nformation f rom t he o riginal c haracterisation o f t he m ineral s pecies ( Hurlbut , 1 942 ). B uerger 's ( 1942 ) w ork o n c opper s ulphides s howed t he v alue o f u sing X r ay d iffraction t o s tudy w hole s ystems , e specially w here i nformation o n e lemental c omposition a lone w ould n ot b e v ery h elpful . F or e xample , h e o btained a s ynthetic C uS w hich h e d emonstrated w as s tructurally i dentical t o p ure n atural c ovellite KM ” . X -ray d iffraction ( XRD ) h as p roved t o b e b etter t han a ny o ther m ethod f or t he i dentification o f n atural m inerals , a nd f or c rystalline c orrosion p roducts a s w ell, b ut o ther t echniques c an n ow b e u sed t o c omplement XRD a nalyses ; t echniques t hat w ere n ot a vailable t o t he B raggs o r o ther e arly w orkers . N on-destructive e lemental a nalyses c an b e m ade , r equiring o nly a f raction o f t he a mount o f m aterial o riginally d estroyed i n w et c hemistry , a nd t he s ame s ample c an b e e xamined i n m any d ifferent w ays . T he c ombination o f p hysical e xamination u nder a m icroscope, q ualitative e lemental i nformation a nd t he X RD p owder d iffraction p attern u sually e nsures a c orrect s ample i dentification, even f or a p iece o f m aterial t he s ize o f a p inhead. The m ain r equirements a re t hat a s canning e lectron m icroscope w ith E DAX f acility i s a vailable f or e lemental a nalysis , t he c rystals h ave b een s elected w ith c are a nd t hat t he a nalyst L is a s teady h and f or m ounting t hem V arious r efinements h ave b een m ade t o X RD m ethods i n o rder t o c ope w ith s mall s amples, b oth f or g eological ( Sorem , 1 960 ) a nd m useum ( Bimson, 1 969) a pplications . I n m useums , a t l east , " ... analytical p roblems, i n f act , c an o ften b e s ummed u p a s d emanding t he m aximum a nalytical i nformation o n v irtually n o s ample w ith t he m inimum e xpenditure o f m oney ." ( Barker, 1 965 ). T he n eed i s f or t echniques o f h igh s ensitivity a nd w ide a pplication, w hich a re a lso r elatively i nexpensive . T he s ame r estrictions a pply now, p articularly w here t here i s a r equirement t o m aintain t he p hysical i ntegrity o f a rt o bjects a nd 7 i ntiquities . XRD t echniques d o n ot d estroy t he m aterials t o b e ‘ vestigated , a nd r epeat a nalyses c an b e c arried o ut , a lthough a s ample , 2 s till n eeded . W here s lightly l arger s amples a re a vailable, i .e . l arger t han t he ' pinhead ' o f m aterial m entioned a bove, m odern d iffractometers c an g reatly s peed u p X RD w ork . A l arge n umber o f s amples o f c opper c e . cr ion p roducts h ave r ecently b een a nalysed a t B irkbeck C ollege,

3 00

U niversity o f L ondon, u sing a S iemens D 500 d iffractometer. N ormal, t raditional m ounting t echniques r eouired m any m illigrams o f p owder f or a n a nalysis , s o t hese w ere q uite o bviously u nsuitable . H owever, t he u se o f as ilicon c rystal m onolithic m ount p roved v ery s uccessful, a nd c ould b e u sed w ith s amples d own t o a bout 1 m g . T he b ackground c ontribution f rom t he m onolith w as s mall, a llowing a r eliable a nalysis o f s mall m asses o f s ample p owder t o b e c arried o ut . T he s ample p owder w as p repared i n t he s ame w ay a s f or c onventional p owder c amera work, a nd was t hen d istributed o ver t he s urface o f t he s ilicon c rystal, u sing a t hin f ilm o f s ilicone g rease t o e nsure a dherence i f n ecessary . I f t he s ample w as r otated i n t he X -ray b eam , i t d id n ot r eally m atter i f t he p owder d istribution w as s lightly u neven . U sing a p osition s ensitive d etector, a nalyses c ould b e c arried o ut i n a bout t en m inutes . P rocessing o f t he d ata b y c omputer t ook a f ew m inutes m ore, a nd i dentifications c ould b e m ade b y r eference t o l ibraries o f d ata o n s uitable s tandards . I n t he c ase o f t he c opper c orrosion p roducts, t he t ypical i nvestment o f t ime p er s ample w as 3 0 m inutes . O nly very c omplex m ixtures , o r v ery u nusual m aterials, r equired m ore work t han t his, a nd m ixtures o f t hree p hases w ere r outinely a nalysed w ithin t he t ypical t ime s pan . A nalyses m ade u sing a s cintillation c ounter ( instead o f t he P SD ) t ook m uch l onger . H owever, t he e xtra t ime i nvestment would b e r ewarded w ith t he b est p ossible r esolution, w hich i s e ssential f or c rystallographic w ork . T he r unning c osts o f t he s cintillation c ounter a re l ower t han t he P SD . A lso , u se o f a p ost-sample m onochromator i s t he b est w ay t o m inimise t he b ackground, a nd a t p resent t his c an o nly b e u sed w ith t he s cintillation c ounter . T he s ilicon m ount . a llowed a n a nalysis o f s ingle p hase s amples t o b e d one o n s amples d own t o a bout 1 m illigram i n w eight . A very g ood q uality p attern f or a rchaeological c uprite w as o btained f rom a t iny s craping o f d ark m aterial f rom a v oid i n a c opper a lloy s ection . M ore n ormal s ample m asses w ere f rom f ive t o t en m illigrams , b ut t his s till m eans t hat o nly small s amples h ave t o b e r emoved f rom t he o bject . S ampling i s n ot g oing t o c ause a ny o bvious d amage t o ac orroded o bject, p rovided i t i s c arried o ut w ith s ome c are. T herefore ,

t he m ain a dvantages o f X RD w ith a s ilicon m ount a re t hat

1 . a r eliable a nalysis o f very s mall s amples c an b e made w ithout m uch e xtra e ffort 2 .

t he s ample c an b e r eplaced a fter a nalysis i f n ecessary

3 . multiple a nalyses o f t he s ame s ample c an b e c arried o ut e asily 4 .

i t i s p ossible t o c oncentrate o n s mall a reas o f i ndividual p atterns t o d etermine t he p resence o r a bsence o f p articular p hases.

h is p aper h as a ttempted t o s how s ome o f t he s teps i n t he p rogression , g ards t he c urrent methods u sed i n t he i dentification a nd i nterpretation o f c opper c orrosion p roducts . I t c an b e s een t hat a dvances i n m ineral a nalysis , c hemistry , t heory a nd h ardware h ave a ll c ontributed t o r eaching t he c urrent p osition . T he b enefits o f u sing

3 01

c omplementary t echniques h ave l ong b een u nderstood . T he m aior o nes u sed a re s till m icroscopy a nd X -ray a nalysis, a nd n o o ther s ingle m ethod c ontributes s o m uch a bout i dentification o f c rystalline m aterials a s t hese t wo a pproaches , e ither i ndividually o r i n c ombination . A cknowledgments T he a uthor w ould l ike t o t hank t he S FRC f or t heir f inancial s upport d uring t he y ears 1 984-7, w hen t he r esearch w as c arried o ut a t t he I nstitute o f A rchaeology , U niversity C ollege L ondon . A lso t he G ordon C hilde a nd Margary B equest F unds C ommittee f or s pecific f inancial s upport f or t his p aper. T hanks a re a lso d ue t o D r N .J .Seeley , D r S .Tarling a nd D r D .A .Scott , a nd t o t he C rystallography D ept ., B irkbeck C ollege, U niversity o f L ondon .

R EFFRENCES B arker H ., ( 1965) S pectrographic a nd X -ray d iffraction m ethods i n t he m useum l aboratory . I n A pplication o f S cience i n t he E xamination o f W orks o f A rt M useum o f F ine A rts, B oston p .218-21 B erthelot ( 1894 ) S ur l 'alteration l ente d es o bjets d e c uivre , a u s ein d e l a t erre e t d ans l es m us es C ompte R endu d es S eances d e l 'AcadgMie d es S ciences , P aris 1 18 7 68-70 B imson M . d iffraction B raga W .H . L ondon

( 1969) T he e xamination o f S tud .Conserv . 1 4 8 3-9 & B ragg

W .L .

( 1916)

c eramics

X -rays

a nd

b y X -ray p owder

C rystal

S tructure

B ragg W .L . & C larinabull G .F . ( 1965 ) C rystal S tructures o f M inerals C rystalline S tate S eries , vol 4 L ondon B uerger N .W . ( 1942 ) X -ray e vidence f or t he e xistence o f t he m ineral d igenite , C u 9S5 A mer .Mineralogist 2 7 7 12-16 C hevreul ( 1856 ) M emoire d e M . C hevreul s ur l a c omposition c himigue d es s tatuettes d e b ronze t rouv6es p ar M . Marlette , c onservateur-adjoint d es a ntiguites 4 gyptiennes d u L ouvre, l u äl 'Acaddmie d es S ciences l e 1 3 d 'octobre 1 856 ( Extrait ) C ompte R endu d es S 6ances d e l 'Acaddmie des S ciences, P aris 4 3 7 33-7 a nd 9 89-90 D aubr6e ( 1875) S ur l a f ormation c ontemporaine, d ans l a s ource t hermale d e B ourbonne-les-Bains ( Haute-Marne ), d e d iverses e sp ces m inerales c ristallisees i bid . 8 0 4 61-9 D avy H . ( 182 4/5 ) O n t he c orrosion o f c opper-sheeting b y s ea w ater, a nd o n m ethods o f p reventing t his e ffect P hil .Trans .Roy .Soc . D avy J . ( 1826 ) O bservations o n t he c hanges w hich h ave t aken p lace i n s ome a ntient a lloys o f c opper i bid 1 16(2 ) 5 5-9 F abrizi M . &S cott D .A . a nd p roblems o f i dentity .

( 1987) U nusual c opper c orrosion p roducts I n R ecent A dvances i n t he C onservation a nd

3 02

A nalysis o f A rtefacts 1 31-3

I nstitute o f A rchaeology ,

S ummer S chools P ress

H urlbut C .S . ( 1942 ) S ampleite, a n ew m ineral f rom C huquicamata, C hile A mer .Mineralogist 2 7 5 86-9 L ewin S .Z . &A lexander S .M . ( 1967-8 ) T he c omposition a nd s tructure o f n atural p atinas A rt A rchaeol .Tech .Abstracts , s upplements t o v ols . 6a nd 7 P alache C .

( 1939 )

P artington J .R . L ondon

A ntlerite ( 1957 )

A mer .Mineralogist

A S hort

H istory

o f

2 4

2 93-302

C hemistry

3 rd .ed .

S age ( 1779 ) O bservations s ur l a m ine r ouge d e c uivre O bservations s ur l a P hysique , s ur 1 1 Histoire N aturelle e t s ur l es A rts 1 4(2 ) 1 557 S orem R .K . ( 1960 ) A mer .Mineralogist

X -ray d iffraction t echniques f or s mall s amples 4 5 1 104-8

W eiser H .B . & M illigan W .O . ( 1932) X -ray s tudies o n t he h ydrous o xides , I I: s tannic o xide a nd I II: s tannous o xide J .Phys .Chem . 3 6 3 030-45

3 03

Science and Archaeology Glasgow 1987 Proceedings of a conference on the application of scientific techniques to archaeology Glasgow, September 1987

Part ii

edited by

Elizabeth A. Slater and James 0. Tate BAR British Series 196(ii) 1988

B.A.R.

122 Banbury Rd, Oxford, OX2 7BP, UK

GENERAL EDITORS A.R. Hands, B.Sc., M.A., D.Phil. D.R. Walker, M.A.

BAR -B196(ii), 1988:

'S cience and Archaeology, Glasgow 1987' , Part ii

© The Individual Authors, 1988 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 9781407390093 (Volume I) paperback ISBN 9781407390109 (Volume II) paperback ISBN 9780860545811 (Volume set) paperback ISBN 9781407318165 (Volume set) e-format DOI https://doi.org/10.30861/9780860545811 A catalogue record for this book is available from the British Library This book is available at www.barpublishing.com

P art i i O RGANIC S M ackay W .I. & G abraS anders T .

S ome t extile s amples f rom t he D opartment o f A mazonas, P eru.

3 05

G abra-Sanders T .

U se o f s canning e lectron m icroscopy t o s tudy f ibres i n t extile r emains. D ye a nalysis a t t he N ational M useums o f S cotland.

3 13

G arland A .N.

C ontributions t o p alaeohistology .

3 21

R oberts C .A .

T rauma a nd t reatment i n B ritish a ntiquity: a r adiographic s tudy .

3 39

B artosiewicz L .

B iometrics a t a n E arly M edieval b utchering s ite i n H ungary .

3 61

A ntoine S .E., D resser P .O., P ollard A .M. & W hittle, A .W .R.

B one c hemistry a nd d ietary r econstruction 3 69 i n P rehistoric B ritain: e xamples f rom W essex.

M offatt P .

F ield t ests f or M edieval d umps o f b lood a t S outra, M idlothian.

3 81

D avies G .R. & P ollard A. M.

O rganic r esidues i n a n A nglo-Saxon g rave.

3 91

W ales S . &E vans J .

N ew p ossibilities o f o btaining a rchaeol ogical i nformation f rom c oprolites.

4 03

S hearer G .

C haracterization o f o rganic a rchaeo4 13 l ogical r esidues u sing d iffuse r eflectance F ourier T ransform i nfra-red s pectroscopy .

H eron C . &P ollard A .M.

T he a nalysis o f n atural r esinous m aterials f rom R oman a mphoras.

H ill H .E. & E vans J .

V egeculture i n S olomon I slands p rehistory 4 49 f rom p ottery r esidues.

P owers A .

P hytoliths: m ineral?

H unt C .O. & C oles G .M.

T he a pplication o f p alynofacies a nalysis t o g eoarchaeology .

4 73

W alker R .

G eophysical i nstrumentation f or a rchaeological p rospection.

4 85

D ockrill S .J., P unter J .R. & C ater J .G.

T he u se o f a pplied g eophysical t echniques 4 87 w ithin t wo e xcavation p rogrammes o n t he i sland o f S andy , O rkney .

G illings M . &P oucher A .

P robing t he P oman o ccupation o f t he N orth.489

G arland H .E.

a nimal, v egetable a nd

3 19

4 29

4 59

P ROSPECTION

Aspinall A. & C-.affney C. The role of the Schlumberger array in archaeological prospection, with a note on sample preparation and storage of conducting anomalies used in simulation experiments.

491

Noel M., Bellerby T.J. & Preliminary studies of thermal archaeo­ Branigan K. logical prospection.

495

CDnU1'IM,; & S'l'ATISTICS

Wilcock J.D.

Past and future directions in archaeo­ logical canputing.

Main P.L.

A comp.1ter database at the British �useum 509 Research Laboratory for holding archaeo­ metric data.

Ritchie M., Torsney B. & Willett F.

Objective assessment of nark's chronology 519 of Benin iremorial heads.

Ringrose T.J.

Exploratory multivariate analysis of stratigraphic data: Armstrong's data fran Pin Bole cave re-examined.

521

Biek L.

Archaeology, science and Comesday.

541

Baillie M.G.L. & Brown D.M.

An overview of oak chronologies.

543

Mills C.

Dendrochronology: short of it.

549

497

DATIR;

Groves

c.

& Hillam J.

the long and the

The potential of non-oak species for tree-ring dating in Britain.

567

581 Scott E.M., Baxter M.S., The comparability of results across a Harkness D.D., Aitchison sul:rsection of radiocarbon laboratories. T.C. & Cook G.T. 591

Ramesh R., Bhattacharya S.K. & Gopalan K.

Climatic significance of variations in the width and stable isotope ratios of tree rings.

Aitken M.J., Smith B.W. & Rhodes E.J.

Optical dating:

Bailiff I.K.

The Durham TL dating service.

Sanderson D. & Clark P.

Recent progress in TL dating of Scottish 623 ceramics and burnt stones.

progress report.

611 613

Thermoluminescence dating of Scottish Strickertssoo K., Sanderson, D., Placido F. vitrified forts: new results and a review. & Tate J.O.

625

Williams F., Pollard A.M. An electron spin resonance study of mollusc shells from archaeological & Evans J.C. contexts.

635

Gentles D.S. & Tarling D.H.

Archaeomagnetic directional dating and magnetic analyses with special refrence to a Scottish vitrified dun.

647

SOME TEXTILE SAMPLES F ROM THE DEPARTMENT OF AMAZONAS, PERU

W .Iain M ackay , 1 30, M archmont R oad, E dinburgh E H9 l AQ a nd T hea G abra-Sanders, 1 8, C raigleith H ill P ark, E dinburgh E H4 2 NR T he m isinterpretation o f t he a rchaeological p lant a nd a nimal f ibre e vidence i s a f requent a nd c ommon p roblem . T he r ange o f f ibres a vailable t o p rehistoric m an f or u se i n t he p roduction o f f abrics i s s urprisingly l imited , a nd y et t heir v isual i nterpretation a nd i dentification i s d ifficult . T he i dentification o f f ibres i s i mportant b ecause t he f ibres c an s upply a variety o f i nformation g iving, f or i nstance , i ndications o f t rading c onnections , t he t echnical p rowess o f i ndividuals a nd t he v ariety o f p lants a nd a nimals a vailable i n a p articular r egion. D r M ichael R yder a nd o ne o f t he a uthors ( T . G -S ) h ave a ddressed t hemselves t o t hese p roblems o f i dentification o f f ibres i n as eries o f a rticles d emonstrating v arious a pplications o f s canning e lectron m icroscope ( SEM ) i n t his f ield ( Ryder & G abra-Sanders , 1 985 & 1 987; R yder 1 987 ). T he p roblem o f v isual i nspection a lone h as a lso b een s tudied b y R yan ( 1985 ) w ho s uggests t hat a m icro-anatomical t echnique b e u sed . T hat i s t o s ay a c omparative m ethod i n w hich t he m icroscopic s tructure o f t he f ibre i s c ompared w ith t hose o f r eference s amples o f a k nown t ype a nd p rovenance . T he r ecommended p rocedure i nvolves a nalysing t he f ibre m icroscopically , r ather t han u sing v isual i nspection w ith t he n aked e ye . T his p aper i s c oncerned w ith t he a pplication o f d ifferent m ethods t o t he i nvestigation o f t extile s amples f rom C arajfa, D epartment o f A mazonas, P eru . A rchaeological b ackground We k now i n t he c ase o f S outh A merica ,

a nd m ore s pecifically i n t he c ase o f P eru , t hat t he S paniards i ntroduced a n umber o f a nimals a nd p lants , i ncluding h orses , s heep , p igs a nd g oats a nd , a mongst t he p lants , c itrus t rees, t he g rape-vine a nd a n umber o f t rees . T he i ndigenous w oolb earing a nimals w ere o f t he c amelid f amily , a nd t he n ative p lant f ibres w ere c otton a nd b ast, s uch a s t hose o btained f rom t he a gave ( Agave a mericana ). T herefore , i n t his s tudy o f p re-Columbian t extile f ibres w e c an c oncentrate o n t hese l atter m aterials a nd i gnore t hose f ibres w hich a re t o b e a ssociated w ith t he a rrival o f t he S paniards a nd s ubsequent , -anges i n p ost-Conquest t imes. I n A pril a nd M ay : c .;tituto N acional d e s urveyed t he v alley s ection o f t he v alley

1 986 a n a rchaeological e xpedition f unded b y t he C ultura a nd t he C entro S tudi R icherche L igabue b etween L uya V ieja a nd L uya ( figure 1 ). A t a k now l ocally a s A ispachaca t here i s a l ocality

3 05

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F igure 1 . M ap o f t he p rovinces o f L uya a nd C hachapoyas, P eru ! k nown a s C arajia, w here t here i s al arge c liff o f s edimentary r ocks, m ainly o f t he C hachapoyas a nd C elend n g eological s equence . C ertain m inerals i n t hese r ocks h ave b een l eached o ut a t v arious r ates b y u nderground w ater a nd o ther e rosive a gencies a nd, w ith t ime, h ave f ormed b anding i n t he r ocks. O ften i n t he a reas o f b anding i n t hese c liffs , p articularly i n t he h ollows t hat h ave b een l eft b y e rosion, m onumental s arcophagai c onstructed o f m ud a nd s ticks w ere p laced . T hese s arcophagai o r p urunm achus ( figure 2 ) c ontained m ummy b undles , a nd i t w as o ur i ntention t o s tudy t he t extiles f rom o ne o f t he d amaged p urun-machus . U nfortunately t his w as n ot p ossible . H owever, s ome s mall t extile f ragments w ere r ecovered a t t he b ase o f t he c liff f rom a p urun-machu t hat h ad f allen

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f rom i ts o riginal s ite 1 987)).

( either n o . 1 2 o r n o . 1 5 a t C arajia ( Mackay ,

T he t extile s amples a re l isted b elow , a nd f urther d etails a re g iven i n M ackay ( 1987 ). O ne o f t he a uthors ( T . G -S ) e xamined t he s amples o n a s canning e lectron m icroscope, a nd t he i dentifications a re b ased o n i nformation p rovided b y v isual a nd m icroscopic i nvestigations. I t w as o riginally a ssumed t hat t he t extiles w ould b e o f c otton b ut t hey a re, i n f act , p redominantly o f w ool ( figure 3 ). I t w as a ssumed t hat t hey w ould b e o f c otton b ecause t he m ain r iver v alley i n t he r egion i s t hat r elating t o t he U tkubamba R iver . I n t he Q uechua l anguage u tku m eans c otton, a nd b amba o r pampa i s a l evel a rea o r p latform . T herefore , t his r iver v alley i s k nown a s t he V alley o f C otton o r C otton V alley , a nd i t h as b een c alled t his f or a v ery l ong t ime . A lso , w ool-bearing c amelids t end t o a bound i n t he h ighland a reas b ut , t o o ur k nowledge, t here a re n one t oday i n t he C hachapoyas a rea . T he z one i s e ssentially o ne o f h igh r ain f orest a nd , g enerally s peaking , i s n ot s uitable f or c amelids . H ence t he a ssumption t hat t he s amples w ould b e o f c otton. A rchaeological t extile f inds i n h ighland P eru a nd t he A ndean A rea a re f ew a nd f ar b etween , p articularly s o f or t his z one , a lthough b oth L anglois ( 1940 p .222 ) a nd K auffmann D oig ( 1986 p .8 ) r efer t o e xamples o f w ool a nd c otton r ecovered f rom t his r egion . T he t extiles f rom p urunm achu n o . 7 ( not e xamined ) a nd t he f allen p urun-machus a t n os 1 1 a nd 1 2 o r 1 5 a t C arajia o nly s urvived b ecause t hey w ere p laced u nder s ubstantial r ock l edges, a nd a lso b ecause t hey w ere e ncased i n am ud a nd s tick f rame a nd t hus p rotected f rom t he w orst o f t he r ain a nd a dverse w eather. R esults T he r esults a re s ummarised i n f igure 3 . A n ote o n t he d escriptions - Z s pun y arns a re p roduced b y s pinning f ibres i n ac lockwise d irection a nd S -spun y arns b y s pinning i n a n a nti-clockwise d irection. S ample n o.1 Aplain w eave/rep t extile 5 .5 x 6 .5 CMS. e xecuted i n w ool, s ienna r ed i n c olour . T he w arp i s Zplied a nd f ormed b y t wo Sspun y arns : t he w eft i s Zspun. T he t hread c ount f or w arp a nd w eft i s 4x2 4 p er c m . S EM m icrographs o f t his s ample a re s hown i n f igures 4 a nd 5 . T he s pinning d irection a nd t he p ly c an b e s een c learly i n b oth p hotographs , a nd t he s cale s tructure o f t he f ibres c an b e i dentified a s w ool. S ample n o. 2 A t extile f ragment i n ? t will ( that i s, t wo t hreads a bove a nd t wo b elow ) a pproximately 4 x 4 .5 a ns . e xecuted i n c otton , v arying i n c olour f rom n atural w hite t o c ream c otton . T he w arp a nd w eft a re b oth S -spun w ith a n a verage t hread c ount f or w arp a nd w eft o f 6x 2 0 p er cm.

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S EM NO.

1

2

2 827-3999 2 828-4000

2 831-4001 2 830-4001 2 832-4003

3

4

5

2 850-4006 2 851-4006

2 852-4007

COLOUR

s ienna r ed

MATERIAL

w ool

w hite

c otton

b rown

w ool

r ed

r ed

w ool

w ool

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p lain w eave 1x1

( rep )

?t will 2x2

p lain w eave 1x1

p lain w eave 1x1

p lain w eave 1x1 ( ? )

6

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c otton

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D IRECTION

ANGLE OF

OF TWIST

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F igure 3 . D escription o f s amples

T he c orresponding m icrographs a re s hown i n f igures 6 , 7 a nd 8 . T he p hotomicrographs i n t his c ase s how t he t ypical t wist n ormally a ssociated w ith c otton . T he s pinning d irection i s q uite d ifferent f rom t hat o f w ool ( figure 7 s hows a s trand o f Z -spun , S -plied y arn w hich i s a n e xception s ince t he r est o f t he f abric i s S -spun ). T he s ample i s w ithout d oubt c otton. T he s tructure o f t he f ibre i s c learly v isible. S ample n o. 3 A p lain w eave t extile f ragment, i n r ep t echnique, m easuring a pproximately 4 x 2 c ms ., e xecuted i n w ool. T he p iece w as d yed w ith a c rimson-red p igment . T he y arn i s Z -plied a nd i s f ormed b y t he p lying o f t hree S -spun y arns . T he w eft i s a lso Z -plied b ut i n t his c ase i t i s f ormed b y t wo S -spun y arns . T he t hread c ount f or w arp a nd w eft i s 5x 2 2 p er c m . S ample n o . 4 A p lain w eave t extile f ragment , a lso i n o pen r ep t echnique , m easuring a rTroximately 2 x 1 .5 c ms ., e xecuted i n w ool. T he f ragment i s n ow a f aded r ed , b ut i s l ikely t o h ave o riginally h ad a r ed c olour s imilar

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t o t hat s hown b y s ample 3 . T he w arp i s Z -plied , f ormed b y t hree S -spun y arns ; a nd t he w eft i s Z -plied f ormed b y t wo S -spun y arns . T he t hread c ount f or w arp a nd w eft i s 4 x 2 0 p er c m . T he c orresponding S EM p hotomicrographs a re s hown i n f igures 9 a nd 1 0. T he p hotomicrographs s how t he s tructure o f t he f ibre c learly . I t c an b e i dentified a s w ool, p robably t hat o f ac amelid ( llama o r a lpaca ). S ample n o. 5 T he f ragmentary r emains o f t he s ample a re i nsufficient t o c onfirm t he s tructure a nd t echnique o f t he p iece , b ut i t i s h ighly l ikely t hat i t w as a 1 x 1 p lain w eave, e xecuted i n w ool a nd d yed a s trong c rimson r ed . T he w arp w as Z -plied, m ade u p f rom t hree S -spun y arns , a nd t he w eft Z -plied f ormed b y t wo S -spun y arns . I n t he p hotomicrographs ( figures 1 1 & 1 2 ) t he s cale p attern o f w ool i s o bvious , a nd i t i s l ikely t hat t hey b elong t o t wo d ifferent t ypes o f c amelid ( llama a nd a lpaca ). S ample n o. 6 T his i s t he o ther c otton s ample . T he t hreads h ad n ot b een w oven i nto a f abric a nd a re p robably s till t heir n atural c ream t o b rownish c olour . T he y arn h as a v ery t ight Z -spin . C onclusions T he a im o f t his p aper w as t o i llustrate t he p otential v alue o f t he s canning e lectron m icroscope i n t he s tudy o f a rchaeological t extiles . T he S EM c an b e u sed f or t he g eneral a nalysis o f w eave s tructure , d ue t o i ts w ide r ange o f d epth o f f ield, o r i f am ore d etailed a nalysis i s r equired, f or e xample, o f s pinning t echniques, i t c an b e u sed a t g reater m agnification . H owever, i n a c ase l ike t his i ts m ost o bvious a nd v aluable u se i s a s a n a id t o f ibre i dentification . F ibre i dentification c ould b e c arried a s tage f urther v ia t he s tudy o f t he i nternal s tructure o f t he f ibres ( or t he m edulla o f t he f ibres ). T his m ight e ventually l ead t o a m ethod f or t he r apid i dentification o f d ifferent t ypes o f c amelid w ool . R yder ( 1963 ) h as a lready n oted t hat t he m edulla t ends t o b e m ore m ultipartite i n t he c ase o f l lama f ibres ( 3-4 c hannels ) t han i n t he c ase o f a lpaca w ool. T he S EM h as b een u sed t o g ive a nswers t o s pecific p roblems . I t r emains f or t he a rchaeologist t o d etermine h ow a nd w here t he m aterials w ere o btained, a nd w hat w ere t he t rade r outes . T he p hotomicrographs a re üThea G abra-Sanders.

R EFERENCES K auffmann D oig F .

( 1986 )

S arcöfagos P re-incas

K untur

1

4 -9

L anglois L . ( 1940) U tcubamba . I nvestigaciones a rqueol6qicas e n e l D epartamento d e A mazonas ( conclusior i ) R evista d el M useo N acional I X(2 )

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1 91-226 M ackay W .I . A nalisis t extil : I nforme s obre l os t ejidos h allados p or l a e xpedicidh A ntisuyo ' 86 M .s , U niversity o f S t A ndrews Ryan D .P . ( 1985 ) T he m isidentification o f a ncient E gyptian p lant f ibres V aria E gyptiaca 1 (3 ) 1 43-9 R yder M .L . ( 1963) A s urvey o f t he g ross s tructural f eatures o f p rotein f ibres . I n J .W .S . H earle & R .H .Peters ( eds ) F ibre S tructure 5 34-61 R yder M .L . ( 1987 ) 2 56(1 ) 1 00-107

T he e volution o f t he f leece

S cientific A merican

R yder M .L . & G abraSanders T . ( 1985 ) T he a pplication o f m icroscopy t o t extile h istory T extile H istory 1 6(2 ) 1 23-40 R yder M .L . & G abra-Sanders T . ( 1987 ) A m icroscope s tudy o f r emains o f t extiles m ade f rom p lant f ibres O xford J .Archaeol. 6 (1 ) 9 1-108

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F igure 2 . P urun-machus a t C arajia, P rovince o f L uya

F igure 5 . S ample 1 , Sspun a nd Zplied w ool y arn ( 30 x )

F igure 4 . S ample 1 , Sspun, Z -plied w eft w ool y arn ( 30 x )

F igure 6 . S ample 2 , c otton f ibres ( 30 x )

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F igure 7 . S ample 2 , a Zspun, S - F igure 8 . S ample 2 , t ight Sspun p lied c otton y arn ( 360 x ) c otton y arn i n ?t will w eave ( 30 x )

F igure 9 . S ample 4 , w ool f ibre s howing s cale p attern. L lama o r a lpaca ( 900 x )

F igure 1 1. S ample 5 , w ool f ibre p ossibly l lama ( 900 x )

F igure 1 0. S ample 4 , w ool f ibre s howing s cale p attern . L Lama o r a lpaca ( 900 x )

F igure 1 2. S ample 5 , w ool f ibre p ossibly a lpaca ( 900 x )

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U SE O F S CANNING E LECTRON M ICROSCOPY T O S TUDY F IBRES I N T EXTILE R EMAINS

T hea G abra-Sanders 1 8 C raigleith H ill P ark E dinburgh E H4 2 NR

T he f irst a rchaeological m aterial o n w hich t he a uthor u sed s canning e lectron m icroscopy ( SEM ) c ame f rom s ome t extiles r etrieved f rom t he w reck o f ' The M ary R ose" ( Ryder, 1 985 ). T he s inking o f ' The M ary R ose", a 1 6th c entury w arship , a nd t he s alvage o f t his w ooden v essel i n 1 982 i s w ell d ocumented ( Rule , 1 983 ). T he t extile f ragments , s ubmitted t o R yder a nd G abra-Sanders f or i nvestigation , w ere r etrieved i n 1 981 a nd c omprised w arp a nd w eft y arns f rom w oven c loth a nd k nitted f abrics . T welve f ragments o f w ool, i n c lothing o f s ailors w ho p erished w hen t he Mary R ose s ank o ff P ortsmouth i n 1 545, w ere i nvestigated ( figure 1 ). F leece t ype w as d etermined b y R yder ( 1984 ) i n o rder t o i dentify a ny e volutionary c hanges , a nd t he s amples w ere t hen e xamined b y t he a uthor u sing s canning e lectron m icroscopy ( SEM ). F or t his e xamination , t he a rchaeological m aterial w as p repared u nwashed . Y arns f rom e ach f ragment a nd f ibres t eased f rom t he y arn w ere m ounted o n a 1 3 m m d iameter a luminium s tub u sing d ouble s ided s ticky t ape . . T he s amples w ere t hen s putter-coated w ith g old ( 20 n m ) u sing a P olaron E 5100 c oater, b efore b eing v iewed a t 0 t ilt i n a n I SI-60 s canning e lectron m icroscope i n t he s econdary e lectron m ode a t 3 0 W . T he s canning e lectron m icroscope p rovided a n i nvaluable t ool f or r evealing f ibre d etails , a llowing t hem t o b e i dentified , a nd a spects o f y arn s tructure s uch a s s pinning d irection , w eave p attern a nd f ibre d iameter t o b e i nvestigated . T he m easurements o f f ibre d iameter a re p articularly i mportant f or f leece s tudies . T he s canning e lectron m icrographs o f 2 0 y arns s howed t he d irection o f t he s pinning t wist ( figure 1 ). T here w ere 1 5 S -spun y arns ( figure 2 ), t wo o f w hich w ere f rom k nitted f abrics , s even w arps a nd s ix w efts . T he Z -spun y arns ( figure 3 ) c omprised o f t wo w arps a nd t hree w efts . E ach t ype n early e qually r epresented i n w arps a nd w efts . I n s ix c loths t he t wist w as t he s ame i n w arp a nd w eft w hile i n t wo i t w as d ifferent. T hese f igures d emonstrate t hat t he s ingle y arns w ere s pun i n b oth S a nd Z d irections , b ut t he r eason f or a ny p articular d irection c an o nly b e g uessed a t . I t i s k nown t hat i n f ragments f rom D anish B og b urials ( Haid, 1 980) a s imilar r ange o f t wist h as b een f ound i n t heir s ingle y arns. T he u se o f d ifferently s pun y arn i n w arp a nd w eft p roduces a n e ven f inish i n t he c ompleted t extile a nd c an a lso p roduce a p attern e ffect . A dditionally , t he s canning e lectron m icrographs s howed c learly t he c haracteristic s cale p atterns w hich c onfirm t he i dentification o f a ll t he f ibres a s w ool ( figures 4 , 6&7 ). A s m ost o f t he f ibres r etained t heir c uticular s cales i t w as p ossible t o i dentify k emp , h air a nd w ool

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T ABLE O F W OOLLEN T EXTILE F RAGMENTS N umber

G arment

A ssociation

1 168 1 936

P raid P ose/Stocking ( knitted) C ape J erkin F ragments P at ( knitted) S acking ( twill w ool) F ragments M an 's g arment F ragments ( twill w ool) J erkin F ragments ( twill w ool)

A rmour C lothing

S /S S

P ones

S /S Z /Z S /S S S /Z

2 480/1 2 888/3 2 995 3 108 4 336 4 371/2 4 589 4 692 4 693 4 756

S hoes S hoe

D irection o f s pinning* f or w arp a nd w eft y arns

p ersonal e ffects

Z /S S /? S /S

b asket b asket

S /S ? /Z

*T he w arp i s s tated f irst. F igure 1 T he s amples e xamined

f ibres a ccording t o t heir p attern ( Anon, 1 965 ). I n t he f leece o f s heep t here c an b e u p t o t hree d ifferent t ypes o f f ibre p resent - w ool, h air a nd k emp ( Ryder, 1 968 ). T he w ool f ibre h as a u niaue w aviness a long i ts l ength. T he h air f ibre i s a l ong c oarse f ibre a nd t he k emp f ibre i s e ven c oarser, s hort a nd v ery b rittle . T he a verage d iameters a re 2 0 - 4 0 - 8 0 m icrons d epending o n t he b reed o f s heep . D amage, s uch a s c racks i n t he f ibre, w ere a lso o bserved a nd o ne f ibre b ore t wo f ungal s pores w ith a h ypha g rowing i nto a c rack . T hese a lmost c ertainly r eached t he f ibre f ollowing r etrieval f rom t he s ea ( figure 5 ). T his i nvestigation h as s hown t hat t he S FM overcomes t he g ap i ncurred b etween t he u se o f l ight m icroscopy , a nd i ts l ack o f h igh m agnification, a nd t ransmission e lectron m icroscopy w ith i ts l imited d epth o f f ield f or t he i nvestigation o f t extile r emains . T he S EM c an a lso h e u sed f or o ther a pplications i n r elation t o a rchaeological t extiles s uch a s r evealing m ixtures o f f ibres , w eaving s tructures a nd t extile f ibres p reserved b y m etal c orrosion. A cknowledgments T his p aper i s b ased o n ap oster p resented a t t he C onference w hich w as p resented i n t he n ames o f b oth T bea G abra-Sanders a nd D r M .L .Pyder, a nd D r P yder's c o-operation i n t his a nd o ther work i s very much a ppreciated.

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R EFERENCES A non ( 1965 ), T he I dentification o f T extile F ibres 5 th e d ., I nstitute, M anchester . H ald, M . ( 1980 ), N ational M useum . R ule,

M .

( 1983 ),

T he T extile

A ncient D anish T extiles f rom d ogs a nd B urials D anish

T he M ary R ose ,

C onway M aritime P ress

( 2nd E d . ).

R yder, M .L . ( 1984 ), Wools f rom t extiles i n t he M ary R ose , a s ixteenthc entury E nglish w arship , J . A rchaeol . S cience 1 1, 3 37-343 . R yder, M .L . & G abra-Sanders , T . ( 1 985 ) , t o t extile h istory , T extile H istory 1 6, R yder, M .L . & S tephenson, Y ork: A cademic P ress .

S .K .

( 1968),

' The a pplication o f m icroscopy 1 23-140 . Wool

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G rowth,

L ondon

a nd New

F igure 2 N o. 2 995;

F igure 3

y arn w ith S T wist. M ag.

N o. 4 371/2; y arn w ith Z T wist. M ag.

1 00X

5 00X

F igure 4 N o . 4 336;

F igure 5 N o. 4 336 ;

h airy , m edium a nd f ine w ool f ibres. M ag 1 30X

f ungal s pores a nd h ypha. M ag. 1 500X

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F igure 6 N o .

4 756 ;

s urface s cale p attern o f f ine w ool f ibre . M ag . 1 500X

F igure 7 N o . 4 371/2 ; mosaic s cale p attern o f h airy w ool f ibre . Mag . 2 40X

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D YE A NALYSIS A T T HE N ATIONAL M USEUMS O F S COTLAND

H .E.Garland D epartment o f C onservation a nd A nalytical R esearch, N ational M useums o f S cotland, E dinburgh

T here a re m any h istorical r eferences t o t he m anufacture a nd a pplication o f d yes, w ith m any h aving v ery s pecific p eriods o f u se . N atural d yes w ere s een a s v aluable t rading i tems t hroughout t he w orld a nd a s n ew c ontinents w ere d iscovered a nd e xplored, m ore dyestuffs w ere f ound, a dding t o o r e ven r eplacing dyes a lready i n u se . T ogether w ith s uch h istorical k nowledge, i mportant i nformation c an b e o btained t hrough a nalysis o f d yed m aterial r egarding t he d ate a nd a uthenticity o f a t extile ; t he r esults c an a lso b e u sed b y t extile c onservation s taff t o a id i n t heir c hoice o f c onservation o r d isplay t echniques. I dentification a nd a nalysis o f n atural d yes h as b een c arried o ut a t t he A nalytical R esearch L aboratory o f t he N ational M useums o f S cotland f or a n umber o f y ears . U sing s olvent e xtraction, U .V ./visible s pectroscopy a nd t hin l ayer c hromatography , aw ide r ange o f n atural d yes h as b een i dentified o n t extiles f rom h istorical a nd a rchaeological s ources. H owever, a ny o ne p articular dyestuff c an vary i n i ts e xact c omposition d epending o n t he s pecific o rigin o f t he dye u nder e xamination . A n e xample o f t his i s m adder, o ne o f t he p rinciple d yes o f a ntiquity . T he m ain s ource o f t his d yestuff i s t he g round r oot o f R ubia t inctorum , b ut o ther m embers o f t he R ubiacea f amily - i .e . R ubia p eregrina , R ubia s ikkimensis a nd R ubia c ordifolia - c an a lso b e u sed t o p roduce a r ed d ye . O ther p lant s pecies, f or e xample t he Morindas a nd G alliums , a fford s imilar d yes . I dentification o f t he e xact p lant s ource c ould p rovide a dditional i nformation r egarding t he o rigins o f t he t extile , a nd a id i n i ts c lassification , a nd t o d o t his o ne m ust b e a ble t o s eparate a nd q uantitatively i dentify t he i ndividual d ye c omponents f rom t he t extile a nd m atch t his c omposition t o t hat o f a s pecific m ember o f t he p lant s pecies. T he p oster p resented a t t he C onference i ncluded a d escription o f a n i socratic H igh P erformance L iquid C hromatography s ystem w hich h as b een d eveloped f or t he a nalysis o f m adder d yes e xtracted f rom t he r oots o f m embers o f t he R ubiacea f amily o f p lants . M ethods o f s ample p reparation w ere d escribed , a nd t he r esults o f t his w ork a s a pplied t o f our p lant s amples w ere t abled ; t hese h ave b een p ublished e lsewhere ( Garland, 1 986). T he q uantitative a ssessment o f s ix o f t he m ost c ommon a nd a bundant a nthraquinones f ound i n m adder d ye p lants h as s hown t hat d istinction s hould b e p ossible .

R EFERENCES G arland H .E . ( 1986 ) T he a nalysis o f f adder d yes A rchaeological T extiles 5 4 4-53

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D yes o n H istorical a nd

CONTRIBUTIONS TO PALABOBISTC4 JOGY

A .N . G arland D epartments o f R heumatology & P athology , S topford B uilding, O xford R oad, M anchester M 13 9 PT

I ntroduction F or m ore t han a c entury a rchaeologists , p hysical a nthropologists a nd p alaeopathologists h ave b een e ngaged i n t he a nalysis o f e xhumed h uman r emains, b oth b one a nd s oft t issue, i n a n a ttempt t o l earn m ore a bout h ealth a nd d isease i n p ast p opulations . S uch p alaeopatholoqical s tudies h ave a r ole i n m odern m edicine t hat i s n ot p urely a cademic , i n t hat t hey c an p rovide s pecimens w hich a re u sually u navailable i n t he n ormal m odern p ractice o f c linical m edicine a nd p athology a nd t hey c an p rovide s pecimens which h ave n ot b een modified b y modern p harmacological o r s urgical t reatment . M ore i mportantly s uch s tudies a llow a n o verall h istorical ( or t emporal) p erspective i nto ' modern ' b one a nd j oint d isorders ; i n o ther w ords , t he e xamination o f e xhumed h uman s keletal r emains o ffers a u nique o pportunity t o u ndertake t wo d imensional e pidemiology ( Dieppe & R ogers , 1 985 ). T he e xamination o f h uman r emains f rom a rchaeological s ites h as b een, a nd i s , u ndertaken b y i ndividuals f rom d ifferent a nd o ften d iverse d isciplines . T his w as e mphasised a t ar ecent c onference b y R oberts , w ho s uggested t hat " this h as l ed t o , a nd s till i s l eading t o , ap roliferation o f b one r eports c onsisting m erely o f ac atalogue o f s keletons w ith n o i nterpretation" ( Roberts, 1 986; p .110). I nterpretation i s i ndeed o f p aramount i mportance i n s tudying d isease p rocesses i n e arlier p eoples . Many b one d iseases i nvolve t he w hole t hickness o f t he b one b ut u nfortunately t here i s at endency f or w orkers i n t he f ield o f h uman s keletal r emains t o r egard b ones a s c onsisting o f e xternal s urfaces o nly . B one d iseases a re d ynamic p rocesses , aw ide s pectrum o f c hanges a re t o b e e xpected a nd, t o c omplicate t he p icture, m ore t han o ne d isease m ay b e p resent a t a ny g iven t ime . T he w orker w ho a dopts t he t raditional " macroscopic o nly " a pproach t o p alaeopathology i s s everely l imited i n i nterpretative a nd d iagnostic a bility a nd i s e asily m isled . T he l imitations o f t his a pproach w ere d iscussed a t a s ymposium o n h uman p alaeopathology i n 1 965 , a t w hich t wo p articipants s uggested t hat ... b one a nd d iseases t o w hich i t i s s ubject m ust b e i nvestigated b y m eans o f m ultiple X -ray f ilms a nd multiple s ections" ( Blumberg & K erley , 1 966 ). R adiology i s n ow b eing u sed w ith i ncreasing f requency b ut m ultiple s ectioning o f b one a nd s ubsequent h istological e xamination o f t he s ections a re n ot . I t w ould t herefore a ppear t hat r egardless o f t he p otential o f p alaeopathology t he s tudy o f e xhumed h uman s keletal r emains h as b een , a nd i s s till, h ampered b y af ailure o f w orkers i n t he f ield t o e xploit t he p otential o f s upporting d isciplines a nd

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t echniques. T he p urpose o f t his p aper i s t o o utline t he p otential c ontributions o f one s uch t echnique - n amely h istology - t o t he s tudy o f o steoarchaeological s pecimens . T his w ill b e d one v ia s everal e xamples , b ut f irst I h ave b riefly t o o utline t he m ethodological a pproaches t o p alaeohistology . M ethodological a pproaches t o p alaeohistology T here a re t hree m ain t echniques f or p rocessing b one f or h istology: i .

d ecalcification a nd p araffin w ax e mbedding ' double e mbedding'of u ndecalcified b one i n p araffin w ax p lastic e mbedding o f u ndecalcified b one

1 .Decalcification a nd p araffin w ax e mbedding D ecalcification i s a t echnique c ommonly u sed t o s tudy t he o rganic c omponent o f b one i n i solation . T here a re t wo m ajor t ypes o f d ecalcifying a gents, a cids a nd c helating a gents . I n t his w ork, d ecalcification o f a rchaeological b one i n e ither n itric o r f ormic a cid w as c ompleted w ithin 4 8 h ours a nd f requently r esulted i n v irtual d issolution o f t he s pecimen , w hereas d ecalcification w ith t he c helating a gent E DTA , a lthough a m ore l engthy p rocedure ( e .g . d ecalcification o f a f emoral h ead s lab t akes u p t o 1 0 w eeks ), l eft a n i ntact s pecimen t o b e e mbedded i n p araffin w ax . O nce d ecalcified t he s pecimens c ould b e p rocessed, e mbedded i n p araffin w ax, s ectioned o n a b ase s ledge m icrotome a t a t hickness o f 7ym a nd f inally s tained i n t he u sual w ay . H owever, h istological s ections o f t he d ecalcified a rchaeological bone w ere d isappointing. Although i n s everal i nstances t he m icroanatomy was p reserved ( figure l a ) a nd i t w as p ossible t o t entatively i dentify o steocytes i n a f ew s pecimens , i n t he m ajority o f s ections o btained b y t his m ethod m uch o f t he o rganic c omponent h ad b een l ost a nd o nly a f ew f ragments o f H aversian c anals c ould b e s een ( figure l b ) o r t he whole s ection r esembled a n etwork o f h oles ( figure l c ) ( Garland & F reemont , 1 987 ). 2 . 'Double e mbedding '

u ndecalcified b one i n p araffin w ax

T his i s a p rocedure d esigned t o c ombine t he a dvantage o f p araffin a nd n itrocellulose a s e mbedding m edia a nd i t i nvolves i mpregnating t he s pecimen w ith i ncreasing c oncentrations o f l ow v iscosity n itrocellulose i n m ethylbenzoate p rior t o p araffin w ax e mbedding . A lthough i t w as p ossible t o p rocess b locks o f a rchaeological b one b y t his m ethod a nd t o o btain i ntact 1 0-20 »m t hick s ections f rom s everal o f t he b locks, i n m any i nstances the double embedded blocks b ehaved u npredictably d uring s ectioning a nd t he w ax e mbedding m edium w as i nadequate t o p revent t h e mineralized t issue f rom c rumbling a s i t w as b eing s ectioned .

a mm

3 .Plastic e mbedding o f u ndecalcified b one T he t hird m ethod o f p rocessing b one i s b y u sing a n e mbedding m edium t hat h as a h ardness c omparable w ith t he b one i .e . b y e mbedding t he

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u ndecalcified b one i n r esin . T he o ptimal s ections w ere o btained b y p rocessing a rchaeological m aterial b y t his m ethod . T he r esin e mbedded b locks c ould b e s ectioned i n

two

w ays:

1 . A t 1 0j um o n ap owered m icrotome . T his w as p articularly u seful f or o btaining s ections f rom t he a rticular e nds o f b one o r s ections o f i liac c rest f or h istomorphometry . 2 . c utting s ections a pproximately 2 50 ) 1m t hick o n am acrotome a nd t hen hand-grinding t o a t hickness o f 7 0 . 2 m . X -ray p hotographs o f s ufficiently h igh r esolution f or m icroscopic e xamination c ould t hen b e o btained f rom t hese s ections . T he t echnique o f m icroradiography i s u seful i n p roviding a t opographical v iew o f t he s pecimen a nd a llows a s tudy o f b one m ineral d ensity a nd d istribution ( figure 2 ). Microradiography a nd t hick s tained a nd u nstained h andground s ections h ave b een f ound p articularly u seful b y o ther workers ( e .g . S tout & S immons, 1 979) a nd myself ( Garland, 1 987) f or s tudying a rchaeological b one w hich i s t oo f ragile t o p ermit t he p reparation o f d ecalcified o r u ndecalcified p araffin w ax e mbedded s ections. Uses o f palaeohistology I dentification o f m ineralised m asses r ecovered a t e xcavation O ccasionally m ineralised masses a re f ound a t e xcavation amongst s keletal s pecimens . T he c ontext o f t he m ass a nd i ts s hape m ay p rovide a c lue a s t o i ts o rigin . H owever, a p urely m acroscopic e xamination o f a m ineralised m ass i s u sually i nconclusive b ut s ystematic u se o f t raditional p athological m ethods, i ncluding h istology, c an o ften p rovide a h ighly p robable d iagnosis a s t he f ollowing t wo e xamples w ill s how . E xample I Amass w as f ound i n t he n eck r egion o f a n a dult f emale s keleton, f rom P oundbury , D orset . T he s pecimen w as i rregularly s haped a nd r adiography c onfirmed t hat i t w as i ndeed a m ineralised m ass . A f ragment o f t he s pecimen was p repared f or h istology b y t he m ethods p reviously d escribed . E xamination o f t he h istological s ections s howed t he s pecimen t o c onsist o f a c ortical l amellar b one c overed i n p laces b y w ell p reserved c artilage ( figure 3 ) . T ide m arks ( s ites o f c alcifying c artilage ) w ere p resent s uggesting t he m ass t o h ave c ome f rom a s ite o f e ndochondral o ssification, a nd t here a ppeared t o b e t he r emains o f s hrunken c hondrocytes l ying w ithin s everal o f t he c hondrocyte l acunae . T his would s uggest t he m ass t o b e a n o steophyte f rom a n a rticular s urface. E xample 2 A m ineralised m ass w as r ecovered f rom t he l ower l imb r egion o f a s keleton f rom B arton-on-Humber. Macroscopically t he s pecimen h ad a t ubular s hape r esembling a c alcified a rtery ( figure 4 a ). E xamination o f t he s pecimen h istologically r evealed t hat w as a c alcified a rtery , t hat t here w as g ood p reservation o f t he e lastic f ibres, a nd t hat t he

3 23

t he i ndividual s uffered f rom a dvanced a rteriosclerosis . B one t aphonomy A lmost e very b one r eport b egins w ith s ome s ort o f d escription o f t he p reservation o f t he r emains . S uch d escriptions a re b ased s olely o n t he m acroscopic a ppearances o f t he e xternal s urfaces o f t he b ones . T o q uote a f ew e xamples f rom t he l iterature : " the b ones w ere d ecayed", " the b ones w ere h eavily e roded" , " the b ones w ere w ell p reserved" , " the b ones w ere b adly p reserved ", " the b ones w ere w eathered" . T hese s ubjective t erms a re r eadily a ccepted a s a n i ndication o f t he m acroscopic s tate o f t he b ones b ut t hey g ive l ittle i nsight i nto t he i nteractions w hich h ave t aken p lace b etween b ones a nd t he v arious c hemical a nd p hysical f actors a nd b iological a gents w ithin t he b urial e nvironment i .e . am acroscopic d escription o f t he e xterior s urface o f a b one s ays n othing a bout i ts t aphonomic h istory . T aphonomy i s a n i nterpretative m odel f or a s cientific u nderstanding o f t he i nteractions b etween t he b ones a nd t he b urial e nvironment . T he s ite I w ill u se t o i llustrate t he u se o f b one h istology i n t he s tudy o f t he t aphonomic h istory o f b ones i s t he c harnel d eposit a t R othwell C harnel H ouse , N orthamptonshire . T he c ontents o f t he b one ' crypt ' i n t he P arish C hurch a t R othwell h ave a ttracted i nterest s ince t hey w ere f irst d iscovered a round 1 700 A D . T he c rypt i s o ne o f o nly t wo s urviving m ajor c harnel d eposits i n t he B ritish I sles a nd i s t herefore i mportant n ot o nly i n t erms o f i ts s tructure b ut a lso o f i ts c ontents . T he b ones i n t he c rypt ( figure 5 ) a re m ainly c omprised o f s kulls w hich h ave b een p laced o n s helves a round t he w alls a nd f emora w hich h ave b een p laced i n t wo s tacks d own t he c entre o f t he c rypt . Ar ecent e stimate p uts t he n umber o f s kulls a t a pproximately 6 00 a nd f emora a t 2 500 . S ince t he d iscovery o f t he c rypt , a n umber o f a nthropological a nd p alaeopathological s tudies h ave b een c arried o ut b y i nterested i ndividuals w ho h ave a ll r emarked o n t he d eteriorating c ondition o f t he b ones , a nd a lso t hat t he c rypt i s e xtremely d amp ( see R oberts , 1 984 f or s ummary ). A s ap alaeohistologist, my p art i n t his s tudy w as, b y t he u se o f h istology , t o s uggest t he n ature a nd e xtent o f a ny b one d amage . F or t his w ork, 1 4 b ones a nd b one f ragments f rom r epresentative p arts o f t he c rypt w ere p rocessed f or h istology b y t he t hree m ethods p reviously d escribed . A ll t he s ections r evealed, t o a v arying e xtent , s ome d egree o f p reservation o f h istological s tructure . H owever m any a berrations f rom s uch a n ormal h istological p icture w ere f ound a nd t he f ollowing c lassification i s as ummary d rawn f rom G arland ( 1987 ) a nd G arland e t a l ( 1987). G eneralised d estructive c hanges w ere c haracterised b y g eneral l oss o f m icromorphology i n t he o uter t hird o f t he c ortex ( figure 6 a ), w ith t his p redominantly a ffecting t he o utermost a spect o f t he o steons ( f ig ure 6 b ).

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( figure 6 b ). F ocal d estructive c hanges w ere c haracterised b y f ocal l oss o f c ollagen a nd m ineral a nd w ith z ones o f h ypermineralisation s urrounding t he f oci ( figure 6 c ). L oss o f o rganic m atrix w as s een i n t he d ecalcified s ections a s b roken u p H aversian s ystems ( figure l b ). I nclusions w ere c haracterised f irstly , b y f ungi l ying a mongst t he t rabecular b one a nd w ithin t he H aversian c anals ( figure 6 d ) a nd s econdly , b y b rushite c rystals f ound i n a ssociation w ith c racks a nd f issures r unning t hrough t he b one m icrostructure ( figure 6 e ). I nfiltrations w ere c haracterised h istologically b y ap ositive P erl's r eaction ( Fig . 6 f ). T his h istological s tudy h as d emonstrated a n umber o f p oints i n t he t aphonomic h istory o f t he R othwell b ones : 1 .

t here h as b een d estruction a nd a lteration o f b oth t he o rganic a nd i norganic c omponents ;

2 .

s low p ost-mortem d emineralisation o f t he b ones i s t aking p lace a nd t his m ineral i s b eing r e-precipitated i nside t he b ones , s ome i n t he f orm o f b rushite c rystals . T hese c rystals c an b e c onsidered a s s pace-occupying l esions , a nd a re c ontributing f actors i n t he c racking a nd f issuring o f t he h istological m orphology ;

3 .

l oss o f b oth o rganic a nd i norganic c omponents h as l ed t o s hrinkage a nd c racking o f t he b one m icrostructure ;

4 .

i ntrusive f ungi , a re p resent i nside t he b ones a nd c ontinuing a nd a ccelerating t he d estructive p rocesses ;

5 .

a t s ome s tage i n t he h istory o f t he b one c ollection i ron h as i nfiltrated i nto t he o uter c ortical s urface o f m any o f t he s pecimens

6 .

h istology h as d emonstrated a n umber o f i mportant i mplications f or t he c onservation o f b oth t he c rypt a nd t he b ones ( Garland e t a l, 1 988 ).

t hey

a re

A natomico-pathological a pproach T he n ext u se o f h istology I w ould l ike t o m ention i s i ts r ole i n t he a natomico-pathological a pproach t o d iagnostic d ifficulties i n p alaeopathology . T he m ost f undamental c oncept r elating t o t he i nterpretation o f a bnormal b one c onditions i s t hat a bnormal b one m orphology i s a lways t he r esult o f ad isturbance i n t wo d istinct c ell p opulations - o steoclasts , t he c ells w hich a re r esponsible f or t he r esorption o f b one, a nd o steoblasts , t he c ells w hich l ay d own n ew b one . A lthough a l arge n umber o f d isease p rocesses c an s timulate o r i nhibit t he a ctivity o f o steoclasts a nd o steoblasts, b one c an o nly r eact t o i nsults i n al imited n umber o f w ays . M acroscopically t his c an b e s een a s 1 ) m ore b one 2 ) l ess b one 3 ) d ead b one o r 4 ) d eformed b one ( Hackett, 1 976 ). I n a ny o ne d isease p rocess m ore t han o ne d isease m ay

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b e p resent i n t he s ame b one a t a ny o ne t ime . T herefore t he w orker w ho a dopts t he ' macroscopic only ' approach to t he study of p alaeopathological s pecimens i s s everely l imited i n b oth d iagnostic a nd i nterpretative c apabilities a nd p erhaps c ould e ven b e c alled n aive . B ecause t he m acroscopic a ppearance o f m any d iseases i s s imilar a nd b ecause o f t he p ossibility o f c oncurrent d isease w ithin t he s ame b one, a s imple f our-stage a pproach t o t he s tudy o f p roblematic p alaeopathological s pecimens s hould b e u ndertaken - b ut o nly a fter t he s keleton h as b een e xamined i n i ts e ntirity . S uch a n a pproach , c alled a n a natomico-pathological a pproach , i nvolves 1 .

ap roper u nambiguous m acroscopic d escription o f t he s pecimen , s imple a nd a ccepted t erminology , a nd a dequate p hotography ;

u sing

2 .

ad escription o f t he X -ray o f t he s pecimen ;

3 .

t he r emoval o f o ne o r m ore s labs o f b one f rom t he s pecimen . T he c ut s urface o f t he s lab i s t hen p hotographed a nd d ocumented, a nd t he s labs a re X -rayed ;

4 .

m icroscopical a nalysis o f t he s labs .

T he h istological c omponent o f t his a pproach h as b een o f value i n p alaeopathology i n n umerous c ases a nd,to n ame j ust a f ew , t hese i nclude d ifferentiating b etween l esions d ue t o i nfection a nd t hose d ue t o m alignant t umour ( Cagier e t a l, 1 982 ); s upporting d iagnoses o f, f or e xample, hypervitaminosis A ( Walker, Z immerman & L eakey , 1 982 ); B rodie 's a bscess ( Lagier e t a l, 1 983) a nd s curvy ( Maat &Utterschant, 1 987). A dditionally i t h as a lso b een u seful i n b oth r ejecting a d iagnosis o f P aget 's d isease i n s everal w idely q uoted e xamples ( Cook , 1 979), a nd i n making t he d iagnosis o f P aget 's d isease ( Zimmerman & K elley , 1 982 ); i n p roducing a c lassification o f e xtracortical n ew b one o r t he s o-called ' periostitis ' ( Stothers & M etress , 1 976 ) a nd s tudying t he d evelopment o f d iseases e .g . c aries s icca ( Hackett , 1 981 ). T he c orrelative a natomico-pathological a pproach i s o f p articular value i n s tudying t he a rthropathies i n a ntiquity a s i t a llows t he d ifferent c omponents o f j oint r emodelling t o b e a ssessed, t hese c omponents b eing: 1 ) a lterations o f t he c artilaginous c overing 2 ) i ntrinsic b one r emodelling a nd 3 ) e xtrinsic b one r emodelling . P alaeopathologists s tudy o nly t he l atter t wo o f t hese c omponents a nd i gnore t he f act t hat a j oint i s af unctional u nit c onsisting n ot o nly o f t he e nds o f c ontiguous b ones b ut a lso o f a c artilaginous c omponent . T hese c omponents w hen c onsidered t ogether p resent a c haracteristic h istological s tructural s equence o f n on-calcified a rticular c artilage, c alcified c artilage a nd t hen b one . T he n onc alcified a rticular a nd c alcified c artilage a re s eparated b y at ide m ark a nd t he c alcified c artilage i s s eparated f rom t he u nderlying b one b y a c ement l ine ( figure 7 ). Because of t he f avoured macroscopic-only a pproach t o p alaeopathology i t i s a popular m isconception, b ased o n t he m acroscopic-only a pproach t o p alaeopathology , t hat o nly t he b ony c omponent o f a j oint s urvies . T his i s n ot t rue . Even i n t he m ost

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u nfavourable c onditions f or b one s urvival, a l ayer o f c alcified c artilage f requently r emains a ttached t o t he b one . F or e xample, a m icroradiograph f rom a f ragment o f b one f rom S utton H oo, a s ite n otorious f or h eavily d egraded b urials, r evealed t he p resence o f a l ayer o f c alcified a rticular c artilage ( Garland , i n p rep . ). A c alcified l ayer o f c artilage i s p resent n ot o nly a t t he j unction o f a rticular c artilage, b ut a lso a t m any t endinous a nd l igamentous a ttachments t o b one . T he p reservation o f s uch a l ayer t herefore m ay h ave i mportant i mplications f or t he s tudy o f l esions f ound a t t hose l ocations. H istomorphometry T he f inal u se o f h istology i n t he s tudy o f e xhumed h uman s keletal r emains I w ould l ike t o m ention i s k nown a s h istomorphometry . D uring t he 1 950s a nd e arly 1 960s s tudies w ere u ndertaken t o a ssess t he h istological a ppearance o f n ormal b one t issue a t v arious s tages i n a n i ndividual 's l ife . T hese s tudies d emonstrated i mportant v ariations i n t he s tructure o f c ortical b one a t d ifferent a ges: n amely , t hat t here w as evidence o f r apid t urnover o f g rowing b one t issue d uring c hildhood, w hereas i n o ld a ge t here w as evidence o f e xtensive b one r esorption w ith l ittle o r n o i ndication o f i ncreased b one f ormation . H owever, n one o f t hese s tudies q uantified t he v ariations i n s uch a w ay a s t o e nable a ge a t d eath t o b e e stimated f rom o bservations o n b one m icrostructure. T he f irst m ajor q uantitative o r h istomorphometric s tudy w as t hat o f K erley ( 1965). K erley c ounted f our p arameters - 1 ) n umber o f s econdary o steons ( number o f H aversian s ystems ) 2 ) f ragments o f s econdary o steons ( number o f i nterstitial l amellae ) 3 ) p ercentage o f e xternal c ircumferential l amellae a nd 4 ) t he n umber o f n on-Haversian c anals i n f our d ifferent m icroscopic f ields i n t he o uter t hird o f t he c ortex. S ince t hen , s everal w orkers h ave d evised h istological m ethods f or e stimating t he a ge a t d eath o f s keletal m aterial ( e .g . s ee U belaker, 1 986 ; S amson & B ranigan, 1 987 ). A s t hey c an p rovide g reater a ccuracy o f a ge e stimation f or a dult s keletal r emains t han c an t raditional m acroscopic m orphological m ethods , t hese t echniques h ave b een u seful n ot o nly i n p alaeopathology a nd p hysical a nthropology b ut a lso i n f orensic p athology . S ummary I n t his s hort p aper f our o f t he u ses o f h istology i n t he e xamination o f e xhumed h uman s keletal - m ains h ave b een o utlined a nd i llustrated . O ther p otential u ses o f h istology i nclude t he s tudy o f c remated r emains a nd t he s creening o f a rchaeological b one f or f ungal a nd m ineral i nclusions p rior t o r adiocarbon d ating, b lood g roupinn a nd c hemical a nalysis. W ith s ome f orethought a nd c areful s election o f h istological m ethods f or t issue p rocessing, and w ith s ome b asic k nowledge o f t he h istological a ppearance o f b one, m odern h istological m ethods h ave a

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valuable c ontribution t o make t o t he evaluation o f h uman o steoarchaeological m aterial . T o e xamine h uman s keletal r emains i s a p rivilege n ot a r ight . S urely t he r emains o f o ur a ncestors d eserve t he b est o f a ttention? I e nd w ith a n o pen-ended q uote f rom a r ecent c onference: p alaeopathology a c ottage i ndustry o r a n i nteractive d iscipline?"

" Is

A cknowledgments Ia m i ndebted t o t he a rchaeologists a nd p alaeopathologists w ho h ave p rovided m e w ith material; t o D rs . A .J .Freemont a nd R .W . S toddart f or t heir c ontinued s upport; a nd t o t he M RC f or a p roject g rant. R EFERENCES B lumberg, J .M . & K erley, E .R . ( 1966) A c ritical c onsideration o f r oentgenology a nd m icroscopy i n p alaeopathology . I n Jarcho, S . ( ed ) H uman P alaeopathology , Y ale U niversity P ress , 1 50-70 . C ook D .C . ( 1979) P aget 's d isease a nd t reponematosis i n p rehistoric m idwestern I ndians: a c ase f or m isdiagnosis O SSA 7 4 1-63 D ieppe, P . &R ogers, J . ( 1985) Two-dimensional e pidemiology , B ritish J ournal o f R heumatology 2 4 ( 4 ), 3 10-2. G arland, A .N . ( 1987) A h istological s tudy o f a rchaeological b one d ecomposition . I n B oddington, A ., G arland, A .N . &J anaway, R .C . ( eds ) D eath, D ecay a nd R econstruction : Approaches t o A rchaeology a nd F orensic S cience , Manchester U niversity P ress , Manchester, 1 09-26 . G arland A .N . H oo.

( in p rep . )

H istological

e xamination o f b one

G arland, A .N . & F reemont, A .J . ( 1987) Methodological p alaeohistology , A cta A natomica 1 30, 3 5-6.

f rom S utton

a pproaches t o

G arland, A .N ., F reemont, S toddart, R .W . &J ayson, M .I.V . ( 1987a ) P ost m ortem h istological c hanges a nd t heir i mplications t o t he s tudy o f e xhumed h uman r emains , i bid 1 30, 3 6 . G arland, A .N ., J anaway, R .C . & R oberts, C .A . ( 1988) A s tudy o f t he d ecay p rocesses o f h uman s keletal r emains f rom t he p arish C hurch o f t he H oly T rinity, R othwell, Northamptonshire O xford J .Archaeol . 7 (2 ), 2 35-52 H ackett, C .J . ( 1976) D iagnostic C riteria o f S yphilis, Y aws a nd T reponarid ( Treponematoses ) a nd s ome o ther D iseases i n D ry b ones, S pringer V erlag , B erlin . H ackett C .J . ( 1981) D evelopment o f c aries s icca V irchows A rchives ( Pathol.Anat .) 3 91 5 3-79

i n a d ry c alvaria

K erley , E .R . ( 1965 ) T he m icroscopic d etermination o f a ge A mer. J . o f P hysical A nthropology 2 3, 1 49-64.

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i n h uman b one,

L agier, R ., B aud, C .A , A rnaud, G ., A rnaud, S . & Menk, R . ( 1982 ) L esions c haracteristic o f i nfection o r m alignant t umour i n p aleo-Eskimo s kulls, V irchows A rchives ( Pathol . A nat . ) 3 95, 2 37-43 . L agier, R ., Baud, C .A . &K ramer, C . ( 1983 ) B rodie 's a bscess i n a t ibia d ating f rom t he N eolithic p eriod , i bid 4 01, 1 53-7 . Maat, G .J .R . & Uytterschaut, H .T . ( 1987 ) M icroscopic o bservations o n s curvy i n D utch W halers b uried a t S poitsbergen , P roceedings o f t he 5 th E uropean Meeting o f t he P alaeopathology A ssociation , S ienna, 1 984 , p p . 2 11-19. R oberts, C .A . ( 1984 ) Analysis o f s ome h uman f emora f rom a Medieval C harnel H ouse a t R othwell P arish C hurch , N orthamptonshire , O SSA 9 -11, 1 37-47. R oberts , C .A . ( 1986 ) P alaeopathology : c ottage i ndustry o r i nteractive d iscipline? I n B intliffe, J .L . &G affney , C .F . ( eds ) A rchaeology a t t he I nterface , B AR I S 3 00, p p .110-28 . S amson, C . &B ranigan, K . ( 1987) A n ew m ethod o f e stimating a ge a t d eath f rom f ragmentary a nd w eathered b one . I n B oddington A ., G arland , A .N . & Janaway, R .C . ( eds ) Death , D ecay & R econstruction, Manchester U niversity P ress, Manchester, p p . 1 01-8 . S tothers, D .M . & Metress, J .F . ( 1976) A s ystem f or t he a nalysis o f p athological c hanges i n p rehistoric s keletons , O SSA 2 , 3 -9 . S tout, S . &S immons, D .J . ( 1979 ) U se o f h istology i n a ncient b one r esearch , Y earbook o f P hysical A nthropology 2 2, 2 28-49 . U belaker, D .H . ( 1986 ) E stimation o f a ge f rom h istology o f h uman b one . I n Z in unerman, M .R . &A ngel, J .L . ( eds ) D ating a nd Age D etermination o f B iological Materials , C roc t r t H elm , L ondon , 2 40-47 . Walker, A ., Z immerman, M .R . &L eakey , R .F . ( 1982 ) Ap ossible c ase o f h ypervitaminosis i n H omo e rectus , N ature 2 96, 2 48-50 . Z immerman, M .P . &K elley, M .A . ( 1982 ) Atlas o f H uman P alaeopathology, P raegar, N ew Y ork .

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F igure l a P hotomicrograph o f a d ecalcified p iece o f b one f rom a 1 2th1 5th c entury b urial s howing a ' normal' h istological a ppearance . I n c ortical b one t he c ollagen f ibres o r l amellae f orm c oncentric a rrays a round s mall c anals o r H aversian c anals w hich, i n l ife , c arry t he n eurovascular b undle . T hese f ormations a re k nown a s H aversian s ystems o r o steons ( area w ithin t he s quare ). O steons a re d emarcated f rom e ach o ther b y c ement l ines ( C ). I nterstitial l amellae ( IL ) r epresent t he l amellae l eft b y o steons d estroyed b y g rowth a nd r emodelling o f b one . E mpty o steocyte s paces ( arrows ). S tain : H aematoxylin & E osin .

( H )

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F igure l b P hotomicrograph o f ad ecalcified p iece o f b one f rom R othwell, N orthamptonshire ( Medieval), f ragmentary o steons i ndicated b y a rrows S tain : t oluidine b lue .

F igure l c P hotomicrograph o f ad ecalcified p iece o f b one f rom A sh H ill L ong B arrow . T he w hole s ection r esembles a n etwork o f h oles . S tain : P AS.

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F igure 2 M icroradiograph o f a f ragment o f b one f rom I ndonesia ( c . 2 500 B C ). N on-mineralised a reas a ppear d ark , t he m ost h eavily m ineralised a reas a re p alest . O steons s how d ifferent d egrees o f m ineralisation .

F igure 3 H istological s ection o f a c alcified mass f rom P oundbury, D orset ( Roman ), s howing c ortical l amellar b one ( B ) c overed b y w ell p reserved c artilage ( C ). S tain : t oluidine b lue .

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F igure 4 a

C alcified t ubular m ass f rom B arton-on-Humber.

Figure 4b P hotomicrograph f rom s pecimen i n 4 a, s howing p reservation o f e lastic f ibres . S tain : e lastic v an G ieson .

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g ood

F igure 5 View o f t he Rothwell P arish Church b one c rypt . c ourtesy o f R ob J anaway , U niversity o f B radford .

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P hotograph

F igure 6 a P hotomicrograph s howing g eneralised d estructive c hanges o uter t hird o f c ortex ( area b etween a rrows ). U nstained s ection .

i n

F igure 6 b S ame s ection a s 6 a , b ut u nder h igher p ower . T he g eneralised d estructive c hanges ( G ) p redominantly a ffect t he o uter t hird o f t he c ortex . H aversian c anal ( H ).

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F igure 6 c M icroradiograph s howing f ocal d estructive c hanges ( open a rrow ). A z one o f h ypermineralisation s urrounds s everal o f t he f oci ( closed a rrow ).

F igure 6 d P hotomicrograph s howing f ungi ( arrowed ) t rabecular b one . S tain : P en s ' .

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l ying a mongst t he

F igure

6 e M icroradiograph s howing c racks a nd f issures r unning t hrough

t he b one m icrostructure .

F igure 6 f P hotomicrograph d emonstrating i nfiltration o f i ron ( area b etween a rrows ) i n o utermost a spect o f t he s ection . S tain : P en s ' .

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N ON-CALCIFIED A RTICULAR CARTILAGE

T IDE MARK C ALCIFIED A RTICULAR CARTILAGE

C EMENT L INE

F igure 7

D iagramatic r epresentation o f b one-cartilage i nterface.

T RAUMA A ND T REATMENT I N B RrrIM 1 ANTIQUITY : AR ADIOGRAPHIC S TUDY

C harlotte A .Roberts C alvin W ells L aboratory , S chool o f A rchaeological S ciences, U niversity o f B radford, B radford B D7 1 DP

I ntroduction D etailed r esearch i nto t he p alaeopathology o f t rauma a nd t reatment i n a ntiquity i s , b y n ecessity , r eliant o n r adiographic a nalysis. R adiography i s u sed i n m any a nalytical p rocedures i n a rchaeology , b ut t he s tudy o f h uman r emains s eems t he m ost o bvious u se o f t his t echnique ; b earing i n m ind i ts u se t oday i n m edicine a nd s urgery . T his p aper r eviews t his a spect o f c urrent p alaeopathological r esearch a nd o utlines t he v alue o f r adiography i n d etermining h ow e fficiently f ractures were t reated i n t he past. Without r adiography, t he macroscopic evidence i s i nsufficient t o g ive t he i nformation p alaeopathologists n eed . I t i s p erhaps a ppropriate t o r ecap o n h ow t he s tudy o f h uman r emains h as d eveloped o ver t he y ears . T hese s tudies o f t he r emains o f o ur a ncestors , s tudies w hich a ctually s tarted b ack i n t he 1 9th c entury , h ave f ascinated s everal g enerations b ut t he w ork h as, u ntil r ecent y ears , m ainly s erved t o p rovide b one r eports f or a rchaeologists . T hese r eports a re u seful, b ut p alaeopathologists a re n ow b eginning t o a sk w hat t hese d ata o n h uman r emains a ctually m ean ( Roberts , 1 986 ). T here i s n o r eal p oint i n p roducing a g rocery l ist o f b odies p resent , w ithout t rying t o i nterpret h ow t he i ndividuals l ived, w hat d iseases t hey s uffered f rom a nd, i n particular, how t hey c oped with t heir a fflictions . A g rocery l ist s hould b e j ust t he b eginning, a s t here i s l ittle t ime o r m oney n ow f or s uperficial, u nplanned s tudies o f a nything a rchaeological. T he s tudy o f h uman r emains m ight b e g aining m ore c redibility w ith a rchaeologists a s a valuable p iece o f evidence f or r econstructing t he p ast b ut , w hen u sed a lone, i t p rovides l ittle c onstructive o r i nterpretable d ata . I t h as t o b e r elevant t o t he g eneral a rchaeological s cene . B y s tudying t rauma o r, i n t his c ase, f ractures o f t he l ong b ones ( or t he r esult o f a ny t raumatic event which l eads t o a c omplete o r p artial b reak i n t he c ontinuity o f a ny b one ) a nd h ead i njuries , t here i s a h uge p otential f or t he p rovision o f a u seful i nsight i nto m edical h istory . B reaking b ones i n t he p ast w as v ery much t he s ame a s i t i s t oday . H owever, X -rays w ere n ot available t hen t o a id d iagnosis a nd t herefore, w hilst t he b asic t reatment o f f ractures w as s imilar, t here c ould b e n o c heck o n t he p osition o f t he b ones i n r elation t o o ne a nother e ither b efore o r a fter t reatment . T here i s n ow t he t echnology t o X -ray a ncient h uman r emains t o g ive m ore a ccurate d iagnoses a nd t o d etermine w hether s ome f ractures w ere h ealing b etter t han o thers . I n t he p lanning s tages o f t he p resent r esearch , t he R oman t o l ate a nd p ost-Medieval p eriods w ere s elected f or s tudy b ecause o f t he

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a vailability o f s keletal a nd d ocumentary e vidence . D ata c ollection h as t aken a l ong t ime a nd i nvolved t ravelling a round B ritain t o m useums , u niversities a nd a rchaeological u nits . T o d ate, a pproximately 6 000 s keletons f rom a variety o f s ites h ave b een e xamined . I n a ddition t o t he s keletal e vidence f or t rauma, o ther f orms o f d ata a re b eing c onsulted ( figure 1 ) i n o rder t o e xpand o n t he s keletal i nformation . T here a re m any p itfalls a nd d isadvantages i n u sing a ll t hese t ypes o f e vidence, b ut t hey p rovide d ata t hat s hould a t l east b e c onsulted a nd u sed o r, i f n ecessary , r ejected .

E vidence U sed 1 ) 2 ) 3 ) 4 ) 5 ) 6 )

S keletal M odern c linical A rchaeological I conographical D ocumentary E thnographical

F igure 1 . T ypes o f e vidence u sed i n t he r esearch.

T rauma: i ntroduction T rauma i s p ainful, v isual a nd d ebilitating , a nd i t i s p lainly e vident t hat p eople i n t he p ast, j ust a s n ow , w ould t ry t o a lleviate t heir s uffering. P ain a nd s uffering a ffect a p erson 's w hole l ifestyle, p articularly i n w hat c an a nd c annot b e a chieved. T he s keleton p rovides t he b ody w ith i ts s upporting f ramework a nd p rotects d elicate o rgans o f t he b ody . R egaining m obility a fter a b roken l eg w ould p robably h ave b een e ssential f or s urvival i n t he p ast , a nd i t i s h ardly s urprising t hat e vidence f or t he r eduction a nd s plinting o f f ractured l imbs , a nd t repanation f or h ead i njuries , i s s een . W ithers i n 1 960 p erhaps s tressed t his p oint w hen h e s aid t hat " In t imes o f s tress , p ain o r s orrow , t he h uman b eing w ill g o t o a ny l ength t o t ry t o f ind h elp . .. " ( Withers , 1 960 ). A lleviating p ain a nd t reating f ractures w ere p robably s ome o f t he f irst p roblems w hich e arly s ocieties h ad t o f ace. T he h ypothesis t o b e t ested i n t his r esearch w as t hat p opulations i n a ntiquity w ere a ble, nd h ad t he t echnology , t o t reat b one i njuries . T o t est t his h ypothesis i t w as d ecided t o s tudy t he d ry b one e vidence f or l ong b one f ractures a nd h ead i njuries . T he l ong b ones o f t he a rms a nd l egs w ere s elected f or s tudy b ecause i t w as c onsidered t hat t hese b ones , i f f ractured , w ould h ave c aused m ajor p roblems t o t he i ndividual's w ell-being . F ractures o f t he r ibs, h and a nd f oot b ones w ere o mitted f rom t he d ata c ollection . B y u sing d irect o bservation a nd r adiography t o a ssess t he s tate o f h ealing, a nd b y u sing t hese d ata w ith o ther c lasses o f e vidence , i t w as h oped t hat i t w ould b e p ossible t o r eflect o n t reatments a vailable i n t he t ime p eriods u nder c onsideration - i .e t o c onsider h ow t hese s ocieties c oped w ith t rauma a nd h ow l ifestyle a ffected t he p rocesses i nvolved . F or e xample, a p erson w ith a b roken l eg l iving i n u nhygienic c onditions would f ind

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t hat t he f racture w ould t ake a l ong t ime t o h eal. T he p rocesses i nvolved a re d ynamic n ot s tatic , a nd a re e ssentially m ultifactorially c omplex. A lthough t his s tudy i s n ot y et c omplete , t his p aper i s p resented t o s how h ow r adiography h as h elped i n t he a ssessment o f t he h ealing o f t he l ong b one f ractures . S uch a n e xtensive r adiographic s tudy o f t rauma i n h uman s keletal r emains h as h itherto n ever b een p erformed a nd a nalysed . T rauma s tudies o n h uman r emains h ave t ended t o a ppear a s as ection i n ab one r eport ( e .g W ells, 1 982 ) a nd w orkers t alk a bout f ractures i n p articular p opulations ( e .g . L ovejoy & H eiple , 1 981 ). P eople r eport o n f ractures o f o ne s keleton, o r o ne p articular f racture o f , s ay , t he s kull i s c onsidered ( e .g . C ourville , 1 952 ), a nd t here h as r eally b een l ittle c oncern o n h ow w ell t he f ractures h ave h ealed o r w hether t reatment w as i nvolved . N umbers s tudied h ave b een s mall a nd t he d ata h ave r arely b een e xpanded . T rauma : r adiography I n 1 982 R ogers s aid t hat " A n X -ray i s n ot t he m ost i mportant t hing i n t he e valuation o f t rauma . T he i nitial s tep i n t he c are o f t he i njured s hould b e ac arefully p erformed p hysical e xamination a nd d etermination o f t he m echanism b ehind t he i n jury w henever p ossible" ( Rogers, 1 982 ). H owever, i n p alaeopathology , r adiography i s p erhaps o ne o f t he f ew s imple non-destructive methods of i nvestigation which p alaeopathologists h ave t o g enerate i nformation w hich c annot b e s een o n t he b one m acroscopically . T herefore , t he e valuation o f t rauma r elies h eavily o n t he u se o f r adiography , p articularly t o a ssess t he m echanism b ehind t he i njury a nd t he s tate o f h ealing o f t he f ractured b one . T he s tate o f h ealing i n a f ractured b one, a s w ill b ecome a pparent , i s r elated t o m any a spects o f t he l ifestyle o f t he i ndividual c oncerned , a nd s o t he s tudy o f f ractures c an a ssist i n t he i nterpretation o f o ther f eatures o f s ociety s uch a s d iet a nd l iving c onditions . H istological m ethods m ay a lso h ave t heir p art t o p lay i n t he f uture s tudy o f t rauma b ut , a s y et , t his h as n ot b een p ursued i n p alaeopathological s tudies o f t rauma . P erhaps t he m ain o bjection t o t he u se o f t his m ethod i n t he s tudy o f t rauma w ould b e t hat i t i nvolves t he d estruction o f s amples . H owever, s ome h istological r esearch i s b eing p ursued s uccessfully i n p alaeopathology ( Garland , t his v olume ). W hilst r adiography h as r evolutionised 2 0th c entury o rthopaedics , i t h as a lso b een w ell u sed i n p alaeopathology d espite p roblems o f availability o f t he n ecessary e quipment a nd f unds . I n m odern p opulations i t i s at echnique u sed d uring t reatment a nd i n p re- a nd p ost-treatment a nalysis , w hilst i n p alaeopathology i t i s n ecessarily a p ost-mortem i nvestigation . I n t he m ajority o f c ases e xamined h ere t he f racture h ad a lready h ealed o r s tarted t o h eal a t t he t ime o f d eath a nd s o t he r adiographic f eatures o bserved w ere u sed t o e stimate t he a pproximate s tage o f h ealing r eached a t d eath . T rauma: r adiographic m ethod F ollowing e xamination a nd r ecording o f a ll t he l ong b one f ractures i dentified , t he s pecimens w ere X -rayed i n s tandard c linical v iews i n t wo p rojections a t r ight a ngles t o e ach o ther, a ntero-posteriorly ( AP )

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a nd m edio-laterally ( ML ). A s b ones a re t hree-dimensional a nd a s ingle r adiograph o nly r ecords t he r adiodensity o ver a t wo-dimensional p lane, i t w as c onsidered t hat t hese t wo v iews s hould b e t he m inimum v iews t aken o f a ny p athological b one a s o ne p rojection a lone m ight n ot s how t he f racture ( see f igure 5 ). T hese a ccepted m edical s tandard v iews s hould a lways b e a dhered t o s o t hat c omparison w ith m odern c linical r adiographs i s p ossible , a s s uch a c omparison i s a n e ssential e lement o f p alaeopathological r esearch . B oth t he A P a nd ML v iews w ere r ecorded o n o ne X -ray f ilm s o t hat e asy c omparison c ould b e m ade b etween t hem , a nd o ther p rojections w ere m ade w hen i t w as c onsidered t hat a b etter i mage o f t he f racture w ould b e p roduced . A s l arge n umbers o f X -rays w ere t aken , i t w as n ecessary t o c arefully i dentify t he f ilms w ith l ead m arkers t o a void c onfusion . T he work w as d one o n a S iemens " Orbix" m achine a t t he Royal I nfirmary i n B radford u sing 3 M X UD f ilm c ontained i n ac assette f itted w ith 3 M T 2 s creens . P rocessing o f t he f ilms w as c arried o ut u sing a 3 M X P 507 9 0 s econd p rocessing m achine . T he f ilm u sed w as d onated b y a n X r ay f ilm c ompany a nd t he w ork w as d one o utside n ormal c linical w orking h ours . T he f ilm u sed i s t he t ype n ormally u tilised f or m odern p atients a s i t p roduces c onsiderable i mage d etail a nd, a s i n m odern c linical w ork , t his i s e ssential f or i nterpreting p athological f eatures i n b one m aterial. S ome r adiographs o f t he s maller l ong b ones w ere p roduced o n a " Faxitron " X -ray m achine , ap ortable i ndustrial u nit , w ithin t he S chool o f A rchaeological S ciences a t B radford U niversity . I ndustrex C f ilm a nd m anual p rocessing w ere u sed w ith t his s ystem . T here w ere c ertain d isadvantages w ith t his s ystem i ncluding , i n p articular, t he s ize o f t he m achine w hich l imits t he l ength o f b one w hich c an b e X -rayed i n t he u nit a nd t he t ime i nvolved i n m anual p rocessing o f s o m any X -rays . A n umber o f d ifferent e xposures w ere u sed d etermined b y t he t hickness o f t he b one a nd i ts c ondition . Exposures w ere a djusted u sing t he t hree c omponents o f t he e xposure i .e k ilovoltage ( KI ), m illiamperes OW a nd e xposure t ime i n s econds ( s ). F igure 2 s hows t he o ptimum e xposures f or e ach b one . T he d ifferences i n b one s urvival f rom v arious s ites w as o bviously a d etermining f actor i n t he e xposures u sed . S ome s pecimens h ad d eteriorated s o m uch f rom b urial i n t he g round t hat v ery l ittle p enetration b y X -rays w as n eeded t o s how t he d etails n ecessary . T rauma : r adiographic a nalysis T he m ethodology f or a nalysing t he X -rays a nd t he r easons b ehind t he i mportance o f r ecording p articular d etails a re n ow d escribed, u sing e xamples d rawn f rom t he d ata s et . T he i nformation i s b ased o n c urrent m edical t hinking o n f ractures a nd t heir h ealing a nd t reatment . B y i ts v ery n ature, p alaeopathology r elies h eavily o n d iagnosis b ased o n m odern c linical t heories . T he b asic t reatment o f r eduction ( or p ulling t he f ractured b one e nds a part t o s et t hem i n t he c orrect a lignment ) a nd s plinting ( or u sing a r igid s ubstance t o k eep t he b one e nds a t r est a nd i n c ontact w ith e ach o ther i n o rder t o e nsure u nion ) o f f ractures h as r emained t he s ame t hrough t ime, w hile t echnology a nd d rug t herapy h as i mproved a nd t hus e nabled o rthopaedic s urgeons t o r ehabilitate p atients i n a s horter t ime . F ractures a nd t heir b asic t reatment i n b oth a ncient

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a nd m odern c ontexts c an t herefore b e c onsidered v ery s imilar, a nd s o t he f eatures o bserved o n X -rays o f a ncient s amples c an j ustifiably b e c ompared w ith t hose s een w ith m odern s amples . P articularly r elevant a re t he w ords o f C lark ( 1937) t hat " t here a re s ome s ubjects s uch a s o bstetrics a nd f ractures ( in ) w hich, b ecause o f t here v ery n ature, t here h as b een v ery l ittle c hange" . B y o bserving s pecific X -ray f eatures i t i s h oped t o a ssess h ow w ell t he f ractures h ave h ealed a nd t hen c orrelate t hese d ata w ith o ther t ypes o f a rchaeological e vidence r elevant t o t reatment a nd h ealing o f f ractures .

E xposure C hart f or S iemens O rbix 3 M X UD F ilm w ith 3 M T 2 S creens F FD 230cm , F ocal S pot 0 .3mm , S iemens T ridoros G enerator

K V

R AS

6 7 7 0 6 7

1 0 1 4 1 0

6 7

1 1

6 7 7 0

1 0 1 6

c lavicle

6 5

1 1

s capula

6 7

1 2

s kull

A P a nd L AT . S UP/INF. O BLIQUE

m andible f acial b ones

v ertebrae

L AT . A P

c ervical a nd u pper t h. L AT . o r S UP/INF. l ower t h. a nd l umba L AT . o r S UP/INF .

6 2 6 7

9 1 0

r ibs

6 2

h umerus

6 7

1 6

r adius/ulna

6 5

1 1

c arpals a nd t arsals

6 2

9

p halanges

6 2

8

f emur

6 7

1 6

6 9 6 7 6 5

1 6 1 4 1 2

t ibia/fibula

l arge s mall c hild

F igure 2 . E xposure c hart f or r adiographs.

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9

X -ray r ecording f orm s ite : s ex:

n umber: a ge:

p eriod: b one:

X -ray v iew : e .g. A /P l ateral t ype o f f racture : i s f racture l ine v isible? c ortical c ontinuity : c ancellous c ontinuity: h ealing p rimary c allus: c alcification : s clerosis o f b one e nds: i nfection :

s econdary c allus:

d isplacement a ngular d isplacement i n l ine o f m ovement: d egree o f a ngulation : o verlap o f b one e nds: a mount o f b roken b one i n a pposition : u nderlying p athology : b lood v essel/nerve i njury : a pprox. t ime b etween f racture a nd d eath: o ther f ractures o n t he s ame s keleton : a dditional c omments :

F igure 3 . X -ray r ecord f orm .

E ach r adiograph w as a nalysed a nd r ecorded o n as tandard f orm ( figure 3 ), w hich w as d esigned a fter c onsiderable c onsultation o f c urrent r adiograph a nalytical l iterature , p articularly R ogers ( 1982 ). A n X -ray o f a b one s hows s hadows p roduced b y i ts m ineral c ontent , m ainly c alcium , s o o nly p athological l esions i nvolved i n c alcium d istribution w ill b e v isible . I n t he c ase o f f ractures , t here i s o bviously a c hange i n s tructural c ontinuity . X -ray r ecording f orm : d etails o utlined D etails o f t he c emetery s ite f rom w hich t he i ndividual w as e xcavated , s ite n umber, p eriod , s ex a nd a ge w ere r ecorded a s b asic d ata . T he b one a ffected a nd t he p osition o f t he f racture a s s een o n t he r adiograph w ere n oted . T he a natomical p art o f t he b ody a ffected i s i mportant t o o bserve b ecause s ome f ractures o f s pecific p arts o f t he b ody h eal b etter t han o thers f or m any a nd v aried r easons . F or e xample , af ractured s haft o f t he f emur i s ad ifficult f racture t o t reat e ven t oday a nd i n n ormal c ircumstances t akes l onger t o h eal t han b reaks i n t he o ther m ajor l ong b ones . I n c ontrast, af racture o f t he h umerus w ill b e n aturally r educed ( i .e t he b one e nds p ulled a part ) t o ac ertain e xtent b ecause o f t he w eight o f t he a rm , a nd a f racture o f e ither o f

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s plinted b y t he o ther b one. T his h as i mplications f or t he p roblems w hich p eople w ould h ave f aced i n t reating s pecific f ractures a nd s ometimes i t w ould a ppear t hat d rastic m easures w ere m ade t o b ring t he f ractured e nds o f t he b ones t ogether ( figure 4 ). T he p osition o f t he f racture w as n oted b ecause i t i s w ell k nown t hat f ractures o f l ong b ones a t c ertain l evels c an c ause p roblems w ith h ealing s o t hat , e ven i f ap opulation h ad t he t echnology a nd e xpertise t o d eal w ith t he f racture, t heir a ttempts m ay h ave b een t hwarted b y t he v ery n ature o f t he f racture . F or e xample , a f racture o f t he l ower l eg o r t ibia c an i nterrupt t he b lood s upply t o t he d istal f ragment a nd t hereby d elay o r p revent h ealing t aking p lace . A f ractured h umerus o r u pper a rm a t t he m id s haft c an d amage t he r adial n erve a nd p aralysis o f t he f orearm a nd h and c an o ccur ( Crawford-Adams , 1 983 p .136 ). T he t ype o f f racture g ives a n i ndication o f w hat c aused t he b reak i n t he b one . F or e xample, a t ransverse f racture i s c aused b y ad irect b low t o t he l imb , a nd i n s ome c ases s pecific t ypes o f f racture c an b e r elated t o o ccupation . A p articularly g ood e xample, a lthough n ot d irectly r elevant t o t his r esearch , i s t he c lay s hoveller 's f racture w here t he e nds o f t he s pinous p rocesses a re f ractured ( figure 6 ) a nd i n m odern p opulations t his i s r elated t o s hovelling h eavy s oils ( CrawfordA dams, 1 983 p .96). I n m any c ases t he m acroscopic a ppearance o f t he t ype o f f racture d oes n ot c orrespond w ith t hat o n t he X -ray . I n p alaeopathology t he X r ay a ppearance i s m ore l ikely t o i ndicate t he t ype o f f racture w hich a ctually o ccurred i n l ife . I n a ddition , aw ell h ealed f racture m ay n ot m anifest o utward s ign o f t he t ype o f f racture o riginally p resent a nd s o a r adiograph i s t he o nly w ay o f d etermining t his f eature w ith a ny a ccuracy . T he r ecording o f t he p resence o f af racture l ine o n t he X -ray w as i mportant t o g ive a n i ndication o f t he a ge o f t he f racture ( in r elative t erms a t l east ). A f racture i n t he e arly s tages o f h ealing w ill s how a c lear f racture l ine ( figure 7 ) w hilst o ne t hat h as h ad t ime t o h eal a nd r emodel w ill d isplay a l ine t hat i s l ess c lear o r e ven o bliterated , a f eature a ssociated w ith t he r estoration o f t he o riginal a rchitecture o f t he i nterior o f t he b one ( figure 8 ) . W hen a f racture o ccurs t here i s h aemorrhage f rom h e f ractured b one e nds , a nd e ventually a n i nitial c ollar o f i mmature b one c alled c allus i s f ormed a round t he f racture ( Crawford-Adams , 1 983 ). T here a re t hree a reas w here t he c allus i s f ormed - i ntermediate ( seals a nd j oins t he e nds o f t he b one ), e ndosteal ( unites t he m arrow s pace ) a nd p eriosteal ( arches o ver t he f racture s ite ). I t g ives a c ertain a mount o f r igidity t o t he f racture i n t he f orm o f a n atural s plint a nd i s g radually r educed i n s ize b y o steoclasts a nd t ransformed i nto m ature b one b y o steoblasts . I ts f ormation a nd r emodelling i nto m ature b one d epends o n m any f actors t hroughout t he w hole p rogress o f t he h ealing p rocess . N evertheless , t he a ppearance o f c allus o n a r adiograph i s a nother i ndication o f t he a ge o f t he f racture a nd t he s tage o f h ealing t hat t he f racture h as r eached ( Racers, 1 982 p .111). I n t he f irst f ew w eeks f ollowing t he t rauma , f lecks o f r adiodense m aterial a re v isible i n t he c allus a nd t he c allus h as a f luffy o utline . A s i t m atures t he b orders

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c allus a nd t he c allus h as a f luffy o utline . A s i t m atures t he b orders b ecome m ore d istinct a nd t he r adiodensity b ecomes m ore u niform . A s t he c allus i s c alcified, t he X -ray s hows i t a s m ore o paque t han t he s urrounding b one . W ith t ime , a nd a s t he f racture b ecomes m ore a nd m ore s table, t he d ensity o f t he c allus b etween t he f racture f ragments a pproaches t hat o f n ormal b one ( figure 9 ). T his c an b e t aken t o i ndicate t hat t he f racture h as u nited . I t i s g enerally a greed i n t he c urrent m edical l iterature t hat a b roken l imb c an b e p erfectly f unctional e ven t hough t here m ay s till b e a f racture l ine p resent o n t he r adiograph , a nd t he f racture l ine i s u sually t he l ast p art o f t he b reak t o b e r emodelled . T he f inal c onsolidation o f af racture i s s hown o n t he X -ray a s a u niform , u ninterrupted o ssification o f c allus, a bsorption a nd c onsolidation o f t he c allus a nd t he d evelopment o f c ontinuous t rabeculae a cross t he f racture s ite . A l arge a mount o f c allus e vident o n e xamination o f t he X -ray ( figure 1 0 ) c an i ndicate m any t hings ( Rogers , 1 982 ). O ne m ajor e xplanation c ould b e t he a bsence o f a dequate i mmobilisation, a s m ovement o f t he b one e nds s timulates t he p roduction o f l arge a mounts o f c allus , a nd t hus t his c ould i ndicate p oor c are o r n o c are a t a ll .

LW

34 W 3 -6 W

i f (

, C-. 7 _ 1 1 7 : L)

4W 4W -

.1 I

-- - --

-

6-8W

6ew

8 12 W

8 1C W - -

U1 2W

1 . 3W

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5C W

F igure 1 1 . A verage d uration o f h ealing ( in w eeks ) o f d ifferent b ones o f t he b ody . A fter S chlosser ( 1968 ).

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T he h ealing o f f ractures i s d ependent o n m any f actors w hich t his r esearch i s h oping t o t ake i nto a ccount . E ven t oday t he n ormal h ealing p rocess d iffers f or d ifferent f ractures a nd a natomical a reas o f t he b ody . T he a ge o f t he p atient a lso h as a s ignificant e ffect o n h ow f ast t he f racture h eals ( e .g a f racture o f t he f emur s haft t akes 3 w eeks t o h eal a t b irth , 8w eeks a t 8y ears , 1 2 w eeks a t 1 2 y ears a nd 2 0 w eeks a t o ver 2 0 y ears ), b ut a verage t imes f or h ealing c an b e g iven , a nd t hese a re s hown i n f igure 1 1 . T hese a nd t he o ther f actors a lready m entioned m ust a ll b e b orne i n m ind i n t he f inal i nterpretation b ut , i n g eneral t erms , t he b etter t he f racture h as b een t reated t he l ess w ork t he b ody h as t o d o t o r ealign t he f racture f ragments a nd h ence t he b etter t he f unctional r esult . D isplacement o f t he f racture f ragments w as r ecorded b y m easuring w ith a r uler a nd p rotractor o n t he X -ray i tself ( figure 1 2 ). T his w as t he o nly w ay t o m easure a ngular d isplacement a ccurately , a s t rying t o d o s o o n t he b one i tself w as l iable t o g ross e rrors . R otational d isplacement c ould o nly b e a ssessed r oughly . I t w as i mportant t o n ote t he r elationship b etween t he l ongitudinal a xes o f t he f racture f ragments a s t his g ives a n i ndication o f t reatment b y r eduction a nd s plinting ( figure 1 3 ). I n m any c ases m uscular c ontraction a t t he t ime o f i njury c an p resent d ifficulties f or r eduction o f t he f ragments . A ngular d eformities c an u sually b e c orrected b y a dequate r eduction, a s imple m ethod o f t reatment w ell k nown t o p ast p opulations , b ut u nreduced r otational f ractures - w here t he b one f ragments h ave h ealed i n at wisted p osition - w ill n ot b e c orrected b y a ny a mount o f r emodelling a nd t heir h ealing c an h ave s ignificant e ffects o n a djacent j oint s urfaces c ausing d egenerative j oint d isease a nd/or g eneral i mmobility . T his t ype o f f racture w ould h ave b een t he m ost d ifficult t o t reat i n a ntiquity , e specially w ithout X -rays. T he a mount o f o verlap o f t he f racture f ragments w as a lso m easured o n t he X -ray ( figure 1 4). T his f eature w ould h ave h ad s ignificant i mplications f or t he i ndividual, a nd i s a n i ndication o f w hether t he f racture h ad b een r educed a nd s plinted . O verlap r educes t he o verall l ength o f t he f inal b one a nd a s hortened l eg , f or e xample , c an l ead t o l ow b ack p ain, h ip o steoarthritis a nd f urther p roblems o f m obility . U se o f a n X -ray w as a lso t he o nly w ay t o a ssess t he d egree o f a pposition o f t he f ragments , i .e h ow m uch o f t he b one s urfaces h ad f used t ogether ( figure 1 5 ). A pposition o f a t hird t o a h alf o f t he b roken ends u sually e nsures a g ood f unctional r esult i f t he l ongitudinal a xis i s s traight a nd n ot t wisted . A pposition o f f racture f ragments w ould h ave b een a d ifficult t hing t o a chieve i n a ncient t imes . P roblems w ith t he d ata T he p receding d escription o f r esearch m ethodology m ay a ppear s imple b ut , i n p ractice , t here w ere s everal p roblems 1 . C ollection o f t he s pecimens A c onsiderable a mount o f t ime a nd e ffort w as e xpended o n e stablishing

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were .

I n

s ome

c ases,

m useum i nformation w as s uch

t hat w asted

j ourneys

w ere m ade. Many s keletal c ollections w ere i ncomplete, t here b eing s everal i nstances w here a c emetery p opulation w as s tored i n 2o r 3d ifferent p laces . S ome m useums w ere n ot i n a p osition t o i ndicate t he n umbers o f s keletons o r c ollections u nder t heir c are . T here w ere a lso i nstances w here p athological b ones , i ncluding t hose s howing f ractures , h ad b een s eparated f rom t he r est o f t he s keleton . H owever, m ost o f t he c ollections e ncountered w ere w ell c urated. 2 . M acroscopic r ecording I t w as n ot p ossible t o d etermine t he a bsolute i ncidence o f f ractures i n t he p opulations s tudied . F or t he m ajority o f c emeteries e xamined t here w as i nsufficient i nformation o n n umbers o f b ones p resent , a nd t here w as n o t ime t o d o t hese c ounts . T his w as n ot, h owever, t he a im o f t he r esearch. F ractures i n s ubadult s keletons w ere g rossly m isrepresented . F ractures i n c hildren a re r arely i dentifiable i n s keletal r emains b ecause o f t heir e xcellent h ealing a nd r emodelling w hich o bliterates t he f racture . E ven d etection b y X -ray i s u sually i mpossible o nce t he f racture h as h ealed . T herefore t he a bsence o f e vidence f or b reakage i n s ubadult b ones s hould n ot b e t aken t o i ndicate t hat s uch b reakages d id n ot o ccur, o r t hat w hen t hey d id t hey w ere t reated b etter t han t hose o f a dults . A m ore l ikely e xplanation l ies i n t he a bility o f a c hild 's b ody t o r emodel c allus a nd r einstate t he b one t o an ormal f unction , a nd t his p recludes t he n ecessity f or e fficient t reatment i n m any c ases . O ther t hings t hat a re n ot e asy t o r ecognise n ow a re f ractures t hat o ccurred i mmediately p receding d eath , a s t hey c ould n ot h ave s tarted t o h eal b efore t he i ndividual d ied . T he r eason w hy t hese m ight b e m issed i s t hat t hey a re v ery d ifficult t o d istinguish f rom p ost-mortem b reaks t hat o ccurred e ither d uring b urial o r i n t he c ourse o f e xcavation o r s tudy . S tress f ractures, d ue t o e xcessive a nd p rolonged s trenuous a ctivity , a s s een i n t oday 's a thletes , m ay b e u ndetectable w ithout X r ay a nd t hey o ften h eal l eaving n o i ndication o f t heir p revious e xistence. R adiographic r ecording A lthough i n p alaeopathology t here a re n o s oft t issue s hadows c omplicate i nterpretation, t here a re s ome p roblems t hat a rise e xamination o f t he X -rays .

t o o n

i ) f racture l ine. O bserving f eatures o f t he f racture w as o ften d ifficult b ecause o f p ostm ortem d egradation . S oil w as o ften p resent i n t he m edullary c avity o f t he b one a nd t his t ends t o m ask t he f racture l ine i n s ome c ases. S ometimes i t w as i mpossible t o s ee t he f racture l ine a t a ll, e ven t hough t here w as m acroscooic e vidence o f t he f racture ( figure 1 6). E xtreme c are w as a lso t aken n ot t o m istake v ascular c hannels i n t he b one f or f racture l ines .

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i i )fracture t ype I n s ome c ases t he f racture h ad h ealed s o w ell a nd c ompletely t hat i t w as n ot p ossible t o i dentify t he o riginal t ype o f f racture n or s ee t he f racture l ine . I n a n a dult , i t w as a ssumed t hat t he t rauma h ad o ccurred e ither i n c hildhood, o r i n a dulthood b ut l ong b efore d eath , a nd t hat t he f racture h ad t herefore h ad s ufficient t ime t o h eal a nd r emodel. i ii)infection I t i s d ifficult t o d istinguish b etween r adiolucent a reas o n t he X -ray o ccurring a s p ost-mortem p rocess a nd r adiolucent a reas o f i nfection o r o steomyelitis . F urthermore, a n o steomyelitic l esion w hich h as n ot d eveloped t o t he e xtent w here i t p enetrates t he b one a nd p roduces a s inus f or p us t o d rain c ould s how u p o n a n X -ray a s ar adiolucent a rea ; m acroscopically t his w ould n ot b e v isible . R adiographic c hanges i ndicating i nfection a re p articularly r elevant i n t erms o f t he h ealing o f t he f racture, t he t ype o f f racture a nd t he e nvironment i n w hich t he i ndividual w as l iving . T here a re u sually t wo t ypes o f f racture , s imple a nd c ompound . T he l atter h as a n a ssociated s oft t issue i njury w hich p resents a n o pen c onnection b etween t he a ir a nd t he b one, p otentially a llowing b acteria t o e nter t he b one s o c reating o sseous i nfection . T he f ormer h as n o c onnection . I n a c ompound f racture w ith t his o pportunity f or i nfection a nd t he a dded c omplications o f u nhygienic c onditions t here c ould b e ad elay i n t he h ealing t ime f or t he f racture . v )pethological f ractures O ne t ype o f f racture t hat c an b e i dentified i n h uman r emains i s t he p athological f racture i n w hich a n u nderlying, p re-existing d isease p rocess w eakens t he b one a nd m akes i t l iable t o f racture u nder s tress . A v ery c ommon c ondition , p articularly i n o lder w omen , i s o steoporosis i n w hich t he q uality o f t he b one r emains t he s ame b ut i ts q uantity d ecreases w ith t ime ( figure 1 7) a nd t his h appens p articularly i n t he p elvis , r ibs a nd v ertebrae . T he d elicate b alance b etween b one f ormation a nd d estruction i s l ost , a nd d estruction o vertakes f ormation ( CrawfordA dams, 1 983 p .19). O riginally, i t w as hoped t o i dentify a ny o steoporosis i n t he b ones b y X -ray , a nd t hen r elate i t t o t he p resence o f f ractures . H owever, u nfortunately , p ost-depositional c hange i n b one s tructure d ue t o e xternal a gencies m ade m any o f t he b ones a ppear t o b e o steoporotic a nd t he b one s tructure o ften h ad a ' washed-out ' a ppearance . I n t his i nstance i t w as t herefore i mpossible t o c omment o n w hether t he i ndividual h ad o steoporosis w hich p redisposed t o t he f racture o r w hether o steoporosis d eveloped a fter t he f racture a nd w as d ue t o b ed r est . S uch i s ad isuse a trophic f eature w hich o ccurs u pon p rolonged i mmobilisation . T his f eature c ould w ell h ave g iven s ome i ndication o f t he p revalence o f o steoporosis i n p ast p opulations w ith r eference t o t he o ccurrence o f f ractures . v i ) a ge o f f racture T he c omplete h ealing p rocess , w here t he t rabecular p attern i s r estored a cross t he f racture l ine a nd t he m imimum a mount o f c allus i s p resent , n ormally t akes a bout o ne y ear - a lthough t here a re s ome f actors t hat c an a lter t his ( see a bove ). H owever, i n g eneral, a fter o ne y ear t here i s n o c hange i n e ither t he r adiographic o r h istological a ppearance o f t he f racture . T herefore, a t p resent , i f t he f racture i s w ell h ealed a nd r emodelled i t i s i mpossible t o s ay v ia p alaeopathology w hen i t w as s ustained , o ther t han t hat t his m ust h ave b een a t l east a y ear b efore

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t he i ndividual d ied . H owever, i t i s h oped t hat, i n t he f uture, c omparison b etween X -rays o f m odern a nd a ncient b ones w ill h elp i n t his s ituation, a nd a w ell-catalogued c ollection o f X -rays f rom t he I nstitute o f O rthopaedics i n L ondon i s b eing u sed t o t ry t o d evelop t his a rea f urther . I nterpretation I t i s p erhaps p ertinent t o n ow a sk w hether t reatment o f f ractures w as u ndertaken i n a ncient p opulations . A lthough t he r esearch i s n ot c omplete, i t i s c lear t hat t here i s a v ariation i n h ealing e vident b etween d ifferent p opulations a nd a t d ifferent p eriods . W ithout d irect evidence o f a s plint a ttached t o t he l imb i t i s i mpossible t o b e c ertain w hether o ne w as u sed b ut , a s C larke c omments , " The s imple a nd p rimitive e xpedient o f h olding t ogether t he p arts o f ab roken s taff b y b inding t hem t o t he s ound s haft w ould n aturally o ccur t o a ny p eople o f i ntelligence" ( Clark, 1 937 p .47 ). T he p roblems w ith t he s urvival o f s plints a re : 1 . T hey w ere p robably m ade o f b iodegradeable m aterials s uch a s w ood a nd b ark a nd i n m any i nstances t hey w ould t herefore n ot s urvive t o b e e xcavated . M odern p rimitive s ocieties u se s uch m aterials . 2 . S plints w ere p robably r eused f or o ther p urposes a fter t he f racture h ad h ealed . 3 . W hy b ury a p erson w ith t he s plint a ttached t o t he b one w hen t he f racture h as h ealed? T he o nly s plints t hat h ave ever b een e xcavated h ave b een f ound a ttached t o u nhealed f ractures . H owever, d espite t hese p roblems . t here i s a c lear i ndication f rom d ocumentary a nd a rchaeological e vidence t hat p eople d id u se s plints i n t he p ast . T he o nly w ay t o a ssess t his p roblem i s t o c ompare b oth m acroscopically a nd r adiologically t he d ifferent a natomical f ractures f rom a v ariety o f p opulations a nd p eriods , c onsidering a ll t he f eatures a lready d escribed . I t i s c lear t hat s ome f ractures c ould n ot h ave h ealed i n t he p ositions o bserved w ithout t reatment . T here i s s till a l ot o f i nterpretative w ork t o u ndertake a nd o ther d ata s ets w ill b e i nvaluable . D ocumentary a nd a rt e vidence a re m ajor a reas o f i nformation w hich s hould b e c onsidered , p articularly a s t here i s aa bundance o f evidence o f t hese t ypes i n t he p eriods u nder s tudy . E thnographic e vidence i s a lso i ndispensible . A lthough t he s ocieties f rom w hich t h is c omes a re d istant i n s pace a nd t ime f rom t he a rchaeological m aterial, t hey a re t he n earest w e c an g et t o o ur p ast p opulations . T hey a re w ell c onversant w ith t reating f ractures i n t he c onventional w ay, b ut a re a lso k een t o t reat t hem b y u nconventional m ethods. A rchaeological evidence i s, o f c ourse, i ndispensible a nd a gain t here i s a n a bundance o f a rtefactual, s tructural a nd e nvironmental d ata . T he e fficient h ealing o f f ractures d epends o n m any f actors b ut o f p articular i mportance a re i mmobility , a bsence o f i nfection , g ood b lood s upply , t he c orrect d iet ( e .g . v itamins A , C a nd D ) a nd s pecific h ormones. D iet, e nvironment, h ygiene a nd l iving c onditions a re e xtremely i mportant f or h ealing . R eliance o n e nvironmental a rchaeologists t o

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p roduce d ata r elevant t o t hose a spects o f s ociety i s e ssential f or t his r esearch . A s mokey h ouse, p oor d iet a nd h ygiene a nd a n u nhealthy e nvironment w ill n ot b e a dvantageous f or e fficient h ealing . D id t he p eople h ave t he f acilities t o a llow a p erson t o r est u ntil t he f racture h ealed? C ould t hey s upport t hese p atients? D id t hey h ave h ospitals? I t i s p lain t hat t his p articular t ask o f r econstruction s eems t o b e e ndless a s t here a re m any a venues o f r esearch t o f ollow i n t his i ntegrated p rogramme . T his p aper h as o nly c oncentrated o n t he r adiographic a spects , a spects w ithout w hich t he r esearch w ould n ot b e v alid . R adiography a s a s cientific p rocedure h as h elped t o e xplain t he d ata i n t erms t hat a re r elevant f or a rchaeology . T his i s s urely w hat t he p rincipal a im s hould b e, a nd t his p articular s tudy h as c onsiderable a rchaeological i mplications . I t i s t o b e h oped t hat R osemary C ramp 's c omment m ade i n 1 983 " Palaeopathology s tudies i n B ritain a re u ncoordinated a nd d esperately u nderstaffed, ( so ) t here i s l ittle p ossibility o f c onstructive e xchange b etween t he p alaeopathologist a nd a rchaeologist" - w ill n ot h old t rue f or m any m ore y ears a nd t hat p eople w ill t ake n ote o f t he i mportance o f t he s tudy o f h uman r emains . P alaeopathologists a re o nly b eginning t o l ook a t h uman r emains i n t erms o f r esearch d esigns b ut t hey a lso h ave a l ot t o o ffer t o h elp r econstruction o f p ast s ocieties . T here w ill h opefully s oon b e t he i ncreased c ooperation w ith a rchaeologists t hat h as b een t alked a bout f or s o l ong . A cknowledgments T hanks t o T ony M argel, S enior R adiographer a t B radford R oyal I nfirmary f or p roducing m ost o f t he X -rays, t o K eith Manchester f or m aking h elpful c omments a nd t he P hotography D epartment a t t he U niversity o f B radford f or p roducing t he i llustrations.

R EFERENCES C lark W .A . ( 1937) H istory o f f racture t reatment u p t o t he 1 6th c entury J .Bone & J oint S urgery 1 9(1 ) 4 7-63 C ourville C .B . ( 1952 ) C ranial i njuries a mong C alifornia B ull.Los A ngeles N eurological S oc.

t he e arly I ndians o f 1 7(4) 1 37-62

C rawford-Adams J .

C hurchill L ivingstone

( 1983 )

O utline o f F ractures

L ovejoy C .O . &H eiple K .G . ( 1981 ) A nalysis o f f ractures i n s keletal p opulations w ith a n e xample f rom t he L ibben s ite, O ttawa C ounty , O hio A mer.J.Physical A nthropol. 5 5 5 29-41 R oberts C .A . ( 1986) i nteracting d iscipline t he I nterface R ogers L .R .

Palaeopathology : c ottage i ndustry o r I n J .Bintliff & C .Gaffney ( ei s ) A rchaeology a t

B AR I S 3 00 ( 1982 )

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R adiology o f S keletal T rauma 2 v ols .

L ivingstone S chlosser V .

( 1968)

T raumatologie

T hieme, S tuttgart

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C hurchill

Wells C . ( 1982 ) T he h uman b ones I n A .McWhirr, L .Viner & C .Wells R omano-British C emeteries a t C irencester C irencester E xcavations C ommittee 1 61-75 W ithers R .J.W . 1 -13

( 1960)

O n b one s etting

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Ulster M edical J .

2 9(1 )

F igure 4 . f racture

1 7 t h c entury i llustration o f r eduction o f al ower l eg

F igure 5 . X -ray s howing ( I le n ecessity f or p roducing t wo v iews o f t he f racture ( left : a nterior/posterior , r ight ; m edio-lateral ). L eft s ide : t wo f ractures v isible . R ight s ide : a n a dditional f racture p resent , n ot v isible o n t he a nterior v iew

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F igure 6 . F racture o f t he s pinous p rocesses o f t he i st t horacic a nd 7 th c ervical v ertebrae ( "clay s hoveller 's f racture" ) i n a R oman i ndividual, B aldock , H ertfordshire

F igure 7 . C lear f racture l ine i llustrated o n at ibial X -ray o f a1 2 y ear-old i ndividual f rom R oman C irencester .

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F igure 8 . X -ray o f t he d istal s haft o f af ibula f rom a n A nglo-Saxon i ndividual f rom P orchester C astle s howing r estoration o f t he i nternal a rchitecture o f t he b one a fter f racture

F igure 9 . X -ray o f af ractured t ibia s howing t hat t he d ensity o f t he c allus i s a pproaching t hat o f n ormal b one

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F igure 1 0. X -ray o f ap roximal f racture o f t he u lna s haft i n aM edieval i ndividual f rom L inlithgow w hich h as s timulated a l arge a mount o f c allus f ormation

F igure 1 2. X -ray o f af racture o f t he d istal s haft o f ar adius f rom a M edieval i ndividual f rom B erinsfield s howing t he m ethod u sed t o m easure d isplacement

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F igure 1 3 . X -ray o f f ractures t o t he t ibiae a nd f ibulae o f aR oman i ndividual f rom B aldock , H ertfordshire s howing h ow t he f ilm h elps t o a ssess t he p osition o f t he f racture f ragments . T he s inus w here p us f rom a n i nfection i nside t he b one ( osteomyelitis ) h as d rained i s a rrowed .

I t e a

F igure 1 4. X -ray o f a f ractured f ibula s haft f rom a M edieval i ndividual f rom B illingsgate s howing h ow t he o verlap o f f racture f ragments w as m easured .

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F igure 1 5. X -ray o f a f ractured t ibia a nd f ibula f rom a R oman i ndividual f rom Victoria R oad, W inchester s howing h ow a pposition o f f racture f ragments w as m easured

OM .

' ',Z ,> f re fe •

F igure 1 6 . X-ray o f af ractured s haft o f f ibula ( at t he p roximal e nd ) s howing o bliteration o f t he f racture l ine b y s oil i n t he m edullary c avity i n t he b one .

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F igure 1 7 . A nterior v iew o f a l umbar v ertebra w ith o steoporosis, s howing a c ompression f racture, f rom a n i ndividual f rom t he R oman c emetery a t B aldock , H ertfordshire .

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B IOMETRICS AT AN E ARLY MEDIEVAL BUTCHERING S ITE

I N HUNGARY

L ' asz16 B artosiewicz A rchaeological I nstitute o f t he H ungarian A cademy o f S ciences , H -1250 P udapest, U ri u .49 H ungary

I ntroduction S ettlement r emains f rom t he e arly M edieval p eriod a re , i n a eneral, r are i n H ungary a nd a lso , t o d ate , n o b utchering s ites f rom t his p eriod h ave b een f ound . H owever, a t t he 9 -10th c entury A D r ural s ettlement s ite o f 6 rmenyküt 5 4 a m ajor c oncentration o f a nimal b ones w as f ound . A rchaeological e vidence s uggests t hat t hese r emains w ere d eposited o ver as hort t ime i nterval, a nd t his m ade i t p ossible t o c onduct a d etailed a nalysis o f t he b ones , i ncluding v arious a ttempts t o r econstruct b ody s ize a nd m eat y ields . M aterial a nd m ethods 1 0 .73 k g o f t he 1 2 .19 k g o f b ones i n t he a ssemblage f rom t he s ite o riginated f rom c attle; t he r est c onsisting o f 0 .58 k g s heep b one a nd 0 .32 k g o f t eeth f rom s heep , a nd a nother 0 .56 k g o f b one s plinters t hat c ould o nly b e i dentified a s t he r emains o f s mall a rtiodactyls . T herefore, a ll t he b iometric c alculations w ere c arried o ut o n t he c attle b ones a s t hese p redominated i n t he a ssemblage . T here a re a n umber o f t aphonomic p rocesses t hat c an a ffect b one, a nd i t w as t herefore f ortunate t hat a ll t he m aterial f rom Ö rmenyküt 5 4 i s o f s imilar d ate a nd w as d eposited w ithin a s mall a rea a s t his r emoves t wo o f t he f actors - d ifferential m ineralisation d ue t o v arying p eriods o f b urial a nd i nhomogeneous b urial c onditions - t hat c an i ntroduce b ias . M easuring t he w eight o f b one i s a n i mportant m ethod f or t he e stimation o f m eat c onsumption a t a rchaeological s ites ( K utasiewicz , 1 956 ). I n o rder t o i nvestigate t he r elationship b etween b one a nd m eat w eight , m odern c arcass c ompositional d ata b y K och e l a l ( 1982 ) w ere r ee valuated i n t erms o f t he e stimation o f t he muscle a nd f at o utput o f t he v arious b ody r egions; t hese r egions a re d efined i n f igure 2 . A d iscriminant a nalysis ( Jennrich & S ampson, 1 981 ) p erformed o n t hese d ata s howed t hat t he b one c ontents o f t he e ight r egions a re c orrelated w ith t he m eat a nd f at o f t hat r egion o f t he b ody , a nd a re t he m ost d istinctive c haracters ( F =7 06 .3; d f =7 ; 3 2 ) a nd t hat, a side f rom a s light o verlap b etween b risket a nd p late ( figure 1 ), t he s eparation o f b ody r egions i s c learly d istinct i n m ost c ases a t ac onfidence l evel o f 9 2 .5% . F or e xample, s hank i s c haracterised b y a h igh p roportion o f b one, w hilst f lank i s t he f attiest p art o f t he b ody a nd h as m inimum b one i n i t. T hese r esults e ncouraged t he i dea o f u sing t he s ame d ata i n t he e stimation o f e arly M edieval m eat y ields , i .e . t o c onvert b one w eight i nto m eat/fat w eights u sing d ifferent f actors f or t he v arious p arts o f t he b ody , a lthough i t i s r ecognised t hat d ata d erived f rom t he s tudy o f

3 61

m odern s teers u ndoubtedly o verestimate t he a mount o f f at a nd m eat y ields . T he o riginal s tudy i ncluded A ngus/Hereford c rosses , T arentaise, P inzgauer, S ahiwal a nd B rahman c attle a nd , o f t hese , a t l east t he f irst t wo s hould b e c onsidered i mproved b reeds i n t erms o f b eef p roduction . F or e ach p art o f t he c arcass , c oefficients w ere d eveloped w hich , b y m ultiplying w ith t he b one w eight , a llowed t he e stimation o f m uscle w eight ( M ) a nd f at w eight ( F ) f or e ach b ody r egion ( figure 2 ) . T hese c alculations w ere c ompleted w ith t he e stimation o f f at-free c arcass w eight ( l l artosiewicz , 1 984 ) a nd w ithers h eight . R esults T he r esults a re s ummarised i n f igure 3 a nd, a s m entioned a bove, t hey m ay w ell b e o verestimates i n t erms o f a bsolute v alues b ut t hey d o o ffer am ore a ccurate e stimate o f t he r elative a mount o f m eat a ssociated w ith e ach b ody r egion t han a p urely q ualitative c lassification w ould ( Fretzoi, 1 968 ; U erpmann , 1 973 ). T hese r esults w ere a lso s upported b y o steological e xamination o f t he b ones f rom t his s ite. w hen c omparing t he f at a nd m eat y ields e stimated f or t he m aterial f rom t he Medieval s ite w ith t he m ean s ide w eight f or a m odern s teer ( figure 3 ) i t m ust b e n oted t hat t he a rchaeological m aterial c omprises b ones f rom a t l east 9 i ndividual c attle ; t he n umber o f i ndividuals c omes f rom v isual a ppraisal o f t he a ssemblage u sing E tkdnyi 's ( 1970 ) c riteria r ather t han a s imple m inimum n umber o f i ndividuals ( MNI ) c alculation . I n a ddition t o b ones f rom s mall c ows, t he r emains o f a t l east o ne b ull a nd a y oung h eifer w ere i dentified i n t he a ssemblage .

0 3

VAR IABLE

t 1 1

4C R1 R C C

Oo

LL 2 I L

0PBB7 P P P p

B

SS B

F F

-2 5

-1 2 .5

CAN ON ICAL

1 2 .5

0

VAR IABLE

1

F igure 1 . T he d istribution o f b ody r egions i n t he p lane o f c anonical v ariables r epresenting q ualitative d istinction v ersus c omposition . R esults o f t he d iscriminant a nalysis u sing d ata b y K och e t a l ( 1982 ). = r ound; L = l oin ; 0 = r ib ; C = c huck; F = f lank; P = p late; B = b risket ; S = shank . S equence n umbers s tand f or a roup m ean c oordinates .

3 62

ROUND: M.4 .8B F =0 .5B

LO IN: M=6 .8 B F = 1 .3 B

F LANK: M=83 .8 1 3 F :114 .6

PLATE: M=5 .2 1 3 F =2 .6 B

R IB: M=10 .9B F r - 2 .1B

BR ISKET: M=6 .4 8 . F =3 .0 1 3 SHANK: M=1 .8 8 F =0 . 1 B CHU CK: M=5 .4B F =0 .6B

F igure 2 . B ody r egions u sed i n t his s tudy ( except h ead a nd d ry l imb ) w ith t he c oefficients d eveloped f or t he e stimation o f m eat a nd f at w eights .B =b one; M =muscle ; F= fat W hen c onsidering t he p resence o f t he d ifferent p arts o f t he b ody o f a ny s ingle i ndividual, i t i s c lear t hat o nly a bout 3 .5% o f t he t otal h one i n t he c arcass i s p resent o n t he s ite ( figure 4 ) a nd t hat t his b one c omes f rom a reas o f t he b ody t hat y ield 2 % o f t he t otal m eat a nd m ore t han 5 .5% o f t he f at . T his a pparent b ias t owards t he m ore f atty p arts o f t he c arcass m ight j ust b e ap roduct o f d ifferential s urvival b ut i t c ould a lso b e r elated t o t he b utchering p rocess ( figure 6 ) . T he b ones f rom s ome f atty p arts o f t he c arcass ( e .g . t he f lank ) c an b e r emoved v ery e asily a nd a re t herefore l ikely t o b e l eft i n t he p rocessing a rea, w hereas b ones i n m eaty p arts t end t o r emain i n t he j oint .

3 63

AREA OF THE

WT. OF

BODY

PONE I N

MUSCLE

F AT

THE DEPOSIT

c oefficient

h ead c huck r ib l oin r ound f lank b risket p late s hank d ry l imb ( max )

W eights f or a t otal s ide o f am odern s teer

5 .00 0 .64 0 .57 0 .25 1 .24 0 .12 0 .37 0 .46 2 .08

n ot a vailable 5 .4 1 0.9 6 .8 4 .8 8 3.8 6 .4 5 .2 1 .8 < 1.8

w eight

3 .46 6 .21 1 .70 5 .95 1 0.06 1 .92 0 .83 3 .74

c oefficient

n ot a vailable 0 .6 2 .1 1 .3 0 .5 1 14.6 3 .0 2 .6 0 .1 < 0.1

w eight

0 .38 1 2.00 0 .33 0 .62 1 3.75 0 .96 0 .05 0 .02

1 0.73

3 3.87

2 8.11

1 7.70

9 7.10

2 7.80

F igure 3 . w eight e stimations i n k os b ased o n t he p roportions o f b one, m uscle a nd f at i n m odern s teers . T he t otal s ide w eight o f am odern s teer i s g iven f or t he p urpose o f c omparison . T he f at-free c arcass w eight o f m odern s teers a verages 2 29 .6 k a ( fiaure 4 ) . A s f ar a s t he M edieval m aterial i s c oncerned, t here w as o ne s mall a stragalus i n t he a ssemblage a nd t his w as u sed t o g ive a n e stimate o f 1 67 k g f or t he c arcass w eight o f t he i ndividual i t c ame f rom ( Bartosiewicz , 1 984 ). T hus , r eaardless o f t he a ctual m eat/fat r atio i n t he a nimal, t his i ndividual w eighed a pproximately t hree q uarters t he w eight o f am odern s teer . W ith r egard t o s ize, t he Medieval c attle a t ösr menyk6t 5 4 w ere u ndoubtedly s maller t han m ost m odern b reeds b ut t hey w ere s till l arger ( in t erms o f w ithers h eicf f it ) t han s ome m odern e xamples . T he s ize o f t he a nimals i s k nown b ecause i t i s p ossible t o e stimate t he w ithers h eight o f a n a nimal f rom t he m aximum l ength o f t he m etapodials . I n o rder t o e stablish t he r elationship , 7 3 m odern s keletons w ere e xamined ( Bartosiewicz , 1 985 ). W hen p lotting t he d ecimal l ogarithms o f w ithers h eight a gainst m etapodial l ength t he f ollowing a lometric e quations e merged :

C ows l og w ithers h eight = 0 .932 l og w ithers h eiaht = 1 .149

( loc i m etacarpal l ength ) ( log m etatarsal l ength )

+ 0 .956 + 0 .397

l og w ithers h eight = 1 .426 l og w ithers h eight = 1 .406

( log m etacarpal l ength ) ( loa m etatarsal l ength )

- 0 .189 - 0 .203

B ulls

3 64

S ubstituting m easurements f rom f igure 5 i nto t hese e auations a w ithers h eight o f 1 190 .5 + 2 2 .6 m m i s o btained f or c ows ( n = 6 ) a nd 1 308 .5 + 4 6 .7 m m f or b ulls ( n = 2 ). T hese f igures s uggest t hat, w hilst t he b utchered a t 8 rm6nykdt 5 4 w ere q uite s mall, t hey w ere c omparable i n s ize t o m odern b reeds l ike t he S erbian P ug a o r t he J ersey .

W EIGHT i n k g

w eight p er i ndividual f or t he M edieval m aterial w eight p er i ndividual f or a m odern s teer %M edieval/Modern

B one

M uscle

F at

1 .19

3 .76

3 .12

8 .07

3 5.40

1 94.20

5 5.60

2 29.60

3 .36%

1 .94%

t otal

5 .60%

3 .51%

F igure 4 . C omparision b etween t he w eight o f m uscle a nd f at p er i ndividual f or t he p arts o f t he c arcass f ound o n t he s ite a s c ompared w ith t he m ean c omposition o f m odern s teers

M AX. L ENGTH ( see a lso f ig 7 )

B WAU I P

s capula, l eft h umerus, r ight h umerus, l eft m etacarpus, r ight(f ) m etacarpus, r ight(f ) m etacarpus, l eft m etacarpus, l eft(f ) m etacarpus, l eft m etacarpus, l eft(m ) m etacarpus, l eft(f ) t ibia , l eft c alcaneus, r ight c alcaneus, l eft a stragalus, l eft m etatarsus, r ight(m ) m etatarsus, r ight(f ) m etatarsus, l eft m etatarsus, l eft(f ) ---------------

1 80.1 1 98.5 2 01.4 2 03.0 1 81.9 1 11.6 1 35.4 5 5 .8 2 35.7 2 12.0 2 08 .1

S

5 8.8 5 0.7 _ - , 5 2.9 5 0.9 4 1.0

3 3.2 _ _ 2 7.1 2 2.9 2 3.3 2 3.9

I CKNESS D 4 2.1 6 4.9 6 8.2 5 1.2 _ _ 6 3.8 6 0.4 3 7.0 4 3.8 3 3.7 5 4.2 4 5.7 4 6.6

P 3 7.4 2 6.8 4 6.2

3 9.9

S 1 9.8 _ 2 3.6 2 4.2 2 6.9 2 2.2 2 2.1 2 1.3

D 6 1.1 5 7.2 6 1.9 5 1.1 _ _ 3 2.8 4 7.2 4 6.8 5 2.9 3 1.0 3 0.9 2 7.4 2 8.2

F igure 5 . M easurements i n m m o f t he b ones r ecovered f rom t he b utchering s ite o f O rmenykut 5 4 . *- m edial l ength u sed f or t he c alculation o f f at-free c arcass w eight . P=p roximal; S = s mallest ; D= d istal. ( m ) = m ale; ( f ) = f emale.

3 65

S ummary B iometrical e valuation o f t he m aterial f rom t he O rmenyküt b utchering s ite s uggested t hat t he c attle r emains c ame m ostly f rom a dult a nimals o f as maller t han a verage s ize . K eeping s ize-related p otential b ias i n m ind, i t s till s eems t hat o nly p arts o f t he c arcass w ere d eposited t here . I n a ddition t o t he b ones o f t he h ead a nd t he d ry l imb r egion, t here w as a h igh p roportion o f b ones f rom t he f atty p arts o f t he b ody , a s w as d emonstrated b y an ew q uantification m ethod p roduced u sing a c omparison w ith m odern b utchering d ata. R EFERENCES B artosiewicz L , ( 1984 ) R econstruction o f p rehistoric c attle r epresented i n aB ronze A ge ' sacrificial p it ' B AR I S 2 27 6 7-80 B artosiewicz L . ( 1985) l ong b ones Z ool. A nz.

I nterrelationships i n t he f ormation o f c attle 3 /4 2 53-62

B ökdnyi S . ( 1970) A ,n ew m ethod f or t he d etermination o f t he n umber o f i ndividuals i n a nimal b one m aterial A mer.J .Archaeol. 7 4 2 91-2 J ennrich P . &S ampson P . ( 1981) S tepwise d iscriminant a nalysis . I n W r .JiDixon ( ed ) BMDP S tatistical S oftware U niversity o f C alifornia P ress, B erkeley 5 19-37 K och P .M ., D ikeman M .E . &C undiff LV . o f c attle t ypes J .Animal S c . 5 4/6

( 1982 ) W holesale c ut c omposition 1 160-64

K retzoi M . ( 1968) e tude P algontologiaue . I n V .Ggbori-Csänk ( ed ) L a S tation d u P aleolithique Moyen d 'Ord, F ongrie A kademiai K iado, B udapest 5 9-104 K ubasiewicz M . ( 1956) 0 m etodice b ad6n w ykopaliskowich s zczqtk6v k ostnich z wierzqcych M aterialv Z achodnio-Pomorskie 2 2 35-44 U erpmann F -P ( 1973) A nimal b one f inds a nd e conomic a rchaeology : a c ritical s tudy o f ' osteo a rchaeological ' m ethod W orld A rchaeol . 4 (3 ) 3 07-22

3 66

F igure 6 . M assive h acking m arks a t t he d istal e nd o f t his t ibia i ndicate t hat t he t arsal b ones m ay h ave b een s electively s eparated f rom t he r ound e nd a nd d iscarded w ith o ther b ones o f t he a utopodium

ae l m i ca6 r f a mM ar F igure 7 .A s eries o f h eavily b utchered m edapodials, t he b utchering p robably f or m arrow e xtraction . W ith b ones i n t his s tate i t w as d ifficult t o m easure t heir m aximum l ength .

3 67

B ONE C HEMISTRY A ND D IETARY R ECONSTRUCTION I N P REHISTORIC B RITAIN: E XAMPLES F ROM W ESSEX

S .E.Antoine l P3 , P .Q .Dresser 2 , A .M.Pollard l a nd A .W .R .Whittle 3 S chool

o f C hemistry & A pplied C hemistry , H istory a nd A rchaeology', U niversity o f W ales, C ollege o f C ardiff

G eology D ept .2 ,

D ietary r econstruction o f p rehistoric c ommunities f rom t he s tudy o f s keletal r emains h as g enerally b een a ttempted u sing t wo t echniques 1 ) 2 )

t race e lement a nalysis s table c arbon a nd n itrogen i sotope a nalysis.

T race e lement l evels i n p rehistoric h uman b one h ave p rovided i nformation o n t he d iet o f a ncient c ommunities ( Brown , 1 973 ; G ilbert, 1 975; L ambert e t a l, 1 979; 1 982; 1 984; P arker & T oots, 1 980; P rice e t 44 1 9 ,g ; R unia , 1 987 ; S choeninger, 1 979 ). S table c arbon i sotope r atios ' C/ C ) o f c ollagen e xtracted f rom a rchaeological b one s amples h ave b een u sed e xtensively t o e stimate t he p roportion o f m arine a nd t errestrial r esources , a nd t he p roportions o f C3- v ersus C4plants i n d iet . T he l atter a re o nly o f i mportance i n t he a rid a nd s ubtropical r egions, s ince C4 plants l ike m aize, s orghum a nd m illet h ave o nly r ecently b een i ntroduced i nto E urope . S table n itrogen i sotope r atios - 1 4 ( 1 5 - N / N ) o f b one c ollagen h ave a lso r eceived i ncreasing a ttention o ver t he l ast d ecade ( e .g . DeNiro & E pstein, 1 981 ; N elson e t a l, 1 986 ). T his p aper d escribes t he u se o f s imilar t echniques i n t he s tudy o f b ones f rom s ites i n t he W essex a rea o f B ritain . M aterial a nd m ethods B one s amples w ere o btained f rom S alisbury M useum a nd f rom t he N atural H istory S ection o f t he B ritish M useum . L ong b ones w ere m ostly s ampled u sing A ntoine 's m ethod ( Antoine, 1 987 ), a nd t he r ibs w ere s ampled a s s mall f ragments . T he m aterial f rom S alisbury M useum c omprised s ix s amples f rom t he p rimary N eolithic p hase a t W or B arrow e xcavated b y P itt-Rivers ( 1 89e ), o ne e ach f rom t he B ronze A ge b arrow a t R otherley D own a nd t he L ate N eolithic/Early B ronze A ge s ite a t H andley D own 2 6 ( Pitt-Rivers , 1 898 ) a nd n ineteen s amples f rom t he B eaker P eriod/Early B ronze A ge S hrewton b arrow ( Green & R ollo-Smith, 1 984). A ll t he s amples f rom t he B ritish M useum c ame f rom t he N eolithic l evels a t H ambledon H ill ( Mercer, 1 980 ). C leaned b one s amples w ere a shed a t 5 50 ° C f or a bout 2 4 h ours, a nd t hen e xtracted b y t he c omplete d issolution m ethod ( Szpunar e t a l, 1 978 ). T he c alcium , s trontium a nd m agnesium c ontents w ere m easured b y a tomic e mission s pectroscopy a nd t he z inc l evels b y a tomic a bsorption s pectrophotometry . T he s trontium/calcium r atios w ere c alculated i n t erms o f m g o f s trontium p er g ram o f c alcium . C ollagen w as e xtracted b y t he m ethod d escribed b y D eNiro a nd

3 69

E pstein ( 1978). S ubsequently , a bout 2 g o f C uO w ires w ere p ut i nto s ilica t ubes a nd h eated a t 8 00 ° C f or 2 h ours . A round 4 t o 6m g o f t he p repared c ollagen w as t hen p ut i nto e ach t ube , t he t ubes w ere e vacuated a nd s ealed o n l ine , h eated a t 8 00 ° C f or a f urt t le -r 4 h ours a nd t hen l eft t o c ool s lowly i n t he f urnace . T he r atios o f i 'C/ 12 C a nd 15 N /1 4 N i n t he r esulting 0 02 a nd N2 w ere m easured b y m ass s pectrometry . U sing n ormal p ractice, t f ie r esults w ere t hen c ompared w ith t hose f or s tandard m aterials a nd t he i sotopic f ractionation i n t he s ample w as t hen e xpressed a s / X )

sa mple

: 1 700

s tandard

-

1 } x 1 000 p er m il

1 2 w here i s e ither '3 C o r 15 N a nd X is Co r 14 N . T he s tandards u sed ‘ 7 .re a tmospheric n itrogen f or t he 1 5 N v alues a nd P DB c arbonate f or t he 1 3 C v alues . R esults a nd d iscussion T he r esults o f t he p resent p reliminary i nvestigation a re p resented i n f igures 1 -10. F igures 1 -5 i nclude d ata o n t he N eolithic s amples f rom Wor B arrow , d esignated W B, a nd t he B eaker P eriod/Bronze A ge m aterial f rom R otherley D own , H andley D own a nd S hrewton , c ollectively r eferred t o a s E A . T he r esults f or t he H ambledon H ill b ones a re g iven i n f igures 6 -10. T he c alcium c ontent o f t he N eolithic ( WB ) s amples w as g enerally h igher t han t hat o f t he B ronze A ge ( BA ) s amples ( figure 1 ). P ossible e xplanations f or t hese d ifferences i nclude i ) m ovement o f c alcium i nto t he N eolithic b one f rom g roundwater o r m oisture i n t he s oil d uring d iagenesis o r i i ) l eaching o f c alcium o ut o f t he B ronze A ge b one i nto t he s oil. I t w ould s eem t hat t he l atter p rocess , p ost-mortem l eaching o f c alcium f rom b one t o s oil, i s t he m ost l ikely i n t he c ase o f t hese b ones b ecause t he c alcium c ontent o f a ll o f t hem w as m arkedly l ower t han t hat r eported f or m odern b one ( Price e t a l, 1 985). L eaching o f

3 00

E 2 00 0 ) z

F - WB R -BA

F -BA

H -BA

10 0

F igure 1 . C alcium c ontent o f Wor B arrow ( WB ) a nd B ronze A ge ( BA ) b one s amples. ( F = f emurs, R = r ibs, H = h umeri ).

3 70

c alcium f rom b one h as a lso b een r eported f or o ther a rchaeological s amples ( Lambert e t a l, 1 985; P arker & T oots, 1 980; S toll & N euman, 1 956 ; 1 958 ) a nd V lasak ( 1 982 ) s howed t hat t he c alcium c ontent o f s oil c an i ncrease i n t he i mmediate v icinity o f b uried b ones . F igure 1 a lso s hows t hat t he c alcium c ontent i n t he f emurs, r ibs a nd h umeri o f t he B A s amples w as v ery s imilar, a nd t hus i t w ould a ppear t hat t he d iagenetic c hanges i n t his m aterial h ad p roceeded a t a c omparatively s imilar r ate i n a ll t he v arious s keletal c omponents . T his i s i n c ontrast t o t he f indings o f Vlasak ( 1982 ) a nd L ambert e t a l ( 1 985 ) w ho r eported h igher c oncentrations o f c alcium i n f emurs t han i n r ibs .

4 7 ' 400 i m

F - WB

F -BA

R -BA

H -BA

z =200 c o

F igure 2 . S trontium c ontent o f W or B arrow ( WB ) a nd B ronze A ge s amples . ( F = f emurs, R = r ibs, H = h umeri ).

a w

b one

T he s trontium d istribution i n t he b ones s howed a d ifferent p attern t o t hat o f c alcium ( figure 2 ) b ecause h igher s trontium c ontents w ere r ecorded i n t he B ronze A ge s amples t han i n t he N eolithic Wor B arrow o nes . T his m ay i mply t hat t he B ronze A ge c ommunities c onsumed a m ore v egetable-rich d iet t han t he W or B arrow c ommunity, s ince H atch a nd G eidel ( 1985 ) r ecently r eported t hat h igher c oncentrations o f s trontium i n as keleton w ould i ndicate a p rimarily v egetarian d iet . H owever, t his i dea i s .b ased o n t he s tudy o f as ingle e lement , a nd i f t he z inc c ontent o f t he b ones ( figure 3 ) i s t aken i nto a ccount, a d ifferent c onclusion c an b e p roposed . T he B ronze A ge c m samples have ah igh z inc c ontent a nd, o n t he b asis o f t his p articular e lement, a m ajor d ietary c ontribution f rom a nimal s ources c an b e s uggested ( Hatch &G eidel, 1 985 ), a nd t his i s o bviously a t v ariance w ith t he c onclusions b ased o n t he s trontium d ata . T he b asic p oint i s t hat s trontium a nd z inc a re f ound i n t heir g reatest a bundance i n d ifferent c omponents o f t he d iet ( Rheingold e t a l, 1 983; B eck, 1 985) a nd, w hilst t his m eans t hat t hey w ill v ary i ndependently o f e ach o ther, i t m ight b e e xpected t hat a h igh z inc c ontent (meat-rich d iet ) m ight w ell b e a ssociated w ith a l ow s trontium c ontent ( low c onsumption o f v egetables ), a nd t he p roblem w ith t he B ronze A ge s amples i s t hat t hey h ave a h igh l evel o f b oth e lements . H owever t here i s ap ossible e xplanation f or t his b ecause , a s e xceptions t o t he g eneralisations g iven a bove, c ertain n uts a nd

3 71

s hellfish c ontain h igh l evels o f b oth s trontium a nd z inc ( Gilbert, 1 977 ). T herefore , t he c onsumption o f n uts a s a c omponent o f t he B ronze A ge d iet s eems t o b e ap ossibility f or e xplaining t he g enerally h igher c ontent o f b oth z inc a nd s trontium . T he z inc c ontent o f t he W or B arrow f emurs w as r ather l ow ( figure 3 ) a nd s howed l ittle v ariation b etween t he i ndividual b one s amples . I t m ay b e s uggested a t t his s tage t hat t he Wor B arrow i ndividuals c onsumed l arge a mounts o f v egetable f ood . B ecause t he z inc c ontent o f t he B ronze A ge s amples e xceeded t hat o f t he Wor B arrow s amples, i t i s p ossible t hat t he B ronze A ge i ndividuals i ngested m ore v egetable f ood , r ich i n n uts, a nd a lso h ad a h igher c onsumption o f m eat t han t he Wor B arrow o nes , s ince m eat i s o ne o f t he m ajor s ources f or z inc i n h uman d iets . O ur r esults a lso s how t hat z inc c oncentrations i n t he r ibs e xceeded t hose o f t he f emurs a nd t he h umeri, w ith t he c oncentrations i n t he

2 800 1 • • • •

2 400 R -BA

' , 1 000

6 00 H -BA

F -BA F -WB 2 00

F igure 3 . Z inc c ontent o f t he Wor B arrow ( WB ) a nd B ronze A ge ( BA ) b one s amples . ( F = f emurs, R = r ibs, H = h umeri ).

3 72

f emur a nd h umeri b eing a lmost i dentical. T his i s i n c ontrast t o t he f inding o f L ambert e t a l ( 1985 ) w ho s howed s tatistically i dentical l evels o f z inc i n r ibs a nd f emurs, a nd s uggested m inimal d iagenetic e ffects . N o s uitable e xplanations f or t hese d ifferences c an b e g iven a t t his s tage a nd f urther d etailed s tudy i s n eeded . M agnesium d id n ot s how m uch v ariation i n e ither t he W or B arrow o r B ronze A ge s amples ( figure 4 ). Apart f rom t hree h igh v alues, t he d istribution o f t his e lement w ould a ppear t o b e a lmost i dentical i n b oth c ommunities, a s w ell a s i n t he f emurs, r ibs a nd h umeri o f t he B ronze A ge i ndividuals . T his l evel o f m agnesium c learly s uggests t he c onsumption o f a d iet r ich i n p lant f ood, a nd i s t herefore f urther e vidence f or t he s uggestions a lready m ade . S imilar u niform l evels w ere a lso r eported b y Vlasak ( 1982 ). T he h igh m agnesium c oncentrations i n b ones f rom b oth c o mmunities c ould a lso b e t aken a s e vidence t hat n uts a nd s imilar p lant f ood w ere t he m ain c ontributor o f z inc t o t he d iet a s o pposed t o m eat , a lthough t he r ole o f m eat a s a z inc s ource s hould n ot b e i gnored .

1 800 F -BA m

1 200

8 00

F - WB

R -BA

H BA

U

2

4 00

F igure 4 . M agnesium c ontent o f t he W or B arrow m ” b one s amples . ( F =f emurs, R = r ibs, H = h umeri).

a nd B ronze A ge

( BA )

T he r esults o f t he i sotopic a nalysis ( figure 5 ) c learly s how t hat t he d iets o f b oth c omm Ig lities w ere m ainly f rom C3terrestrial p lants . T he m ean v alue o f i1 ) C f or C3plants i s c lose t o 27 °/ ( Deines , 1 980 ; o o P rice e t a l, 1 985; S mith & ,, Epstein, 1 971; Vogel & Van d er Merwe, 1 977 ), a nd t he v alues o f il J C f rom t he p resent w ork r anged f rom 7 21 » 8 a nd a re t herefore c lose t o t hose g iven a bove . T he t o 23 .3° in / dicate , v alues t hough n ot c onclusiv ly , t he c onsumption o f n on-N 2f ixing t errestrial p lants i n w hich b , 'N v alues a re r eported t o v ary b etween 0 a nd + 6 ° /00 ( Parw € ,11 e t a l, 1 957; P rice e t a l, 1 985; S weeney e t a l, 1 978 ). H owever, m ore r ecent a nalysis o f p rehistoric p lants f rom

3 73

1 9 8 5 ) ,

P eru s uggests t hat t his r ange m ay b e t oo l ow ( DeNiro & H ast9 g , a nd h istoric p opulations r epresenting a griculturalists h ave 1 1 \ Iv alues r anging f rom + 6 t o + 12 °/00 ( Schoeninger e t a l, ) S choeninger e t a l ( 4 so r eported t hat M esoamerican m aize a griculturalists h ave a m ean I J N v alue o f / a nd t heir s ample f rom E uropean N eolithic a griculturalists s how s imilar v alues . T hese p oints a re s ignificant h ere b ecause v alues g reater t han + 6 0 /00 w ere o ften r ecorded i n o ur s amples .

1 9 8 3.

1 9 8 3 )

+ 9 0

,

-BA

JA /L 3—

A

-BA

20

1 0 F - WB

F -BA

R -BA H -BA

V3 C

$ 1 5 N

F igure 5 . T he a nd v alues o f t he W ar B arrow o e A ge ( BA ) b one s amples . ( F = f emurs, R = r ibs, H = h umeri).

a nd B ronze

6 )

T he c alcium c ontent o f t he H ambledon H ill s amples ( figure w as h ighly c omparable w ith t hat o f t he War B arrow f emur s amples . I n f act, t he c alcium c ontept o f t he H ambledon H ill f emurI r anged b etween a nd u g m g ' w ith a m ean o f u g m g - , wile t hat o f t he War Barrow f emurs r anged f rom t o u g m g J - w ith a m ean o f u g m g -1 . T he m ean c alcium c ontents o f f emurs, t ibia/fibula, r ibs a nd h umeri w ere c losely s imilar w hich s uggests t hat t hese b ones w ere w ell p reserved , b ut t here i s a lso t he p ossibility t hat a dditional d eposition o f c alcium t ook p lace d uring d iagenesis a s s ome s amples s howed a s lightly h igher c alcium c ontent t han t hat r eported f or m odern b ones ( Price e t a l,

3 5 . 5

2 3 . 1 1 8 7 . 6 3 1 9 . 9

1 9 8 5 ) .

3 7 4

2 0 . 6 2 5 1 . 0

3 0 C Y )

2 00

F

—

T F _

1 00

F igure 6 . C alcium c ontent o f H ambledon H ill T F =t ibia/fibula, H = h umeri, R = r ibs ).

b one s amples

( F = f emurs ,

T he s trontium v alues f or t he H ambledon H ill s amples ( figure 7 ) e xceeded t hose o f t he Wor B arrow s amples ( figure 2 ), d ue p erhaps t o ag reater d ependence o n p lant f ood . T his i s s upported b y t he s ubstantially h igher m agnesium c ontent ( figure 9 ) i n t he H ambledon H ill m aterial ( c .f f igure 4 ). T he z inc c ontent ( figure 8 ) w as l ower t han i n t he B ronze A ge s amples . T his s uggests e ither l ess d ependence o n m eat o r a l ower c onsumption o f n uts a t t he H ambledon H ill s ite . T he s trontium/calcium r atios s hould r eflect t he a mounts o f t hese t wo e lements a vailable t o t he o rganism v ia i ts d ietary i ntake , a nd t he m etabolism o f s trontium i nto t he b one s tructure ( Comar e t a l, 1 957; P rice e t a l, 1 985). T his i s r eflected i n t he h igher r atios o f t he B ronze A ge s amples ( 0 .72-1.75 ) c ompared t o t he Wor B arrow o nes ( 0 .581 .09 ), a nd i n t he h igher v alues i n t he H ambledon H ill s amples ( 0 .741 .63 ) c ompared w ith t he W or B arrow m aterial, s uggesting a h igher a vailability o f s trontium i n t he B ronze A ge a nd H ambledon H ill d iet a s c ompared t o t he Wor B arrow o ne . D iagenetic variations o f c alcium c ontent a lso p lay a b ig r ole i n t he e stimation o f t his r atio, s ince a l arge a mount o f c alcium m ay b e l ost t o t he s oil o r c alcium c ould m igrate f rom t he s oil t o t he b one, t hus c hanging t he c alcium c ontent d uring b urial. T he p ossibility o f s uch d iagnetic c hanges d oes m ean t hat r atios i nvolving c alcium a re n ot p articularly r eliable w hen d ealing w ith a rchaeological m aterial ( Beck, 1 985 ), a nd i t i s t herefore r ecommended t hat t he i nterpretation o f s trontium l evels s hould b e b ased o n a bsolute v alues a nd n ot r atios a gainst c alcium . L ambert e t a l ( 1982 ) a lso r eported t hat, a lthough t he S r/Ca r atio i s o f u ndoubted u se i n b iomedical d iscussion o f m odern b one , d ifferential d iagenetic e ffects o n t he t wo e lements r equire t hat t heir p roportions s hould b e d iscussed s eparately i n a rchaeological s tudies . I sotopic r atios a re n ot s ubject t o s uch s evere d iagenetic a lteration, a nd a re t herefore m uch m ore r eliable i n p alaeodietary r econstruction . T he 1 ;1 ) C v alues o f t he H ambledon H ill s amples ( figure 1 0) a re w ithin t he r ange o f v alues i ndicating a d iet c onsisting g f 1N t errestrial C 3-plants , a nd t he a nimals c onsuming t hese p lants . T he

3 75

10 ,

T F

0 )300 E2 00 0

10 0

F igure 7 . S trontium c ontent o f H ambledon H ill T F =t ibia/fibula, H = h umeri, R = r ibs ).

b one s amples

( F = f emurs ,

b 4 00 ( 3 ) 3 00 c

2 00

N

100

TF

-

F igure 8 . Z inc c ontent o f H ambledon H ill b one s amples t ibia/fibula , H = h umeri , R = r ibs ).

( F = f emurs, T F =

1

1 200 ( 3 )

c »

T F

E 8 00 . ) c 4 00 0 ; 5 2

F igure 9 . M agnesium c ontent o f H ambledon H ill b one s amples ( F = f emurs , T v =t ibia/fibula, H = h umeri, R = r ibs ).

3 76

-2 4

-1 2

1 6

F TF

4

F igure 1 0 . T he 1 3 C a nd 5 15 N v alues o f H ambledon H ill b one c ollagen s amples ( F = f emurs , T F = t ibia/fibula , H= h umeri, R = r ibs ).

v alues w ere a lso w ithin t he r ange o f v alues i ndicating t he c onsumption o f n on-nitrogen-fixing t errestrial p lants . A cknowledgments T his w ork i s p art o f S ERC R esearch G rant G R/D/66319 . T he a uthors t hank D r T .Molleson , D epartment o f P alaeontology , B ritish Museum ( Natural H istory ) a nd Ms C .Coneybeare, Assistant C urator ( Archaeology ), S alisbury a nd S outh W iltshire M useum f or p roviding t hem w ith t he b one s amples.

3 77

R EFERENCES A ntoine S .F . ( 1987) A s imple t echnioue f or s ampling a rchaeological b one t issue C ircaea 4 1 03-5 P eck L .A . ( 1985 ) B ivariate a nalysis o f t race e lements i n b one J .Human E vol. 1 4 4 93-502 B rown A .A . ( 1973 ) B one S trontium C ontent a s D ietary I ndicator i n H uman S keletal P opulations U npublished P hD t hesis , U niversity o f M ichigan C omar C .K ., R ussell L . & Wasserman R . m ovement f rom s oil t o m an S cience 1 26

( 1957) 4 85-6

S trontium-calcium

D eines P . ( 1980) T he c omposition o f r educed o rganic c arbon . I n P .Fritz & J .Fontes ( eds ) H andbook o f E nvironmental I sotope G eochemistry 3 29-406 D eNiro M .J . & E pstein S . ( 1978 ) I nfluence o f d iet o n t he d istribution o f c arbon i sotopes i n a nimals G eochim .Cosmochim .Acta 4 2 4 95-506 D eNiro M .J . & E pstein S . ( 1981 ) I nfluence o f d iet o n t he d istribution o f n itrogen i sotopes i n a nimals G eochir.Cosmochim.Acta 4 5 3 41-51 A a nd 13 C / 12 C D eNiro M .J . & H astorf G .A . ( 1985) A lteration o f 1 5m/14 -1 r atios o f p lant m atter d uring t he i nitial s tages o f d iagenesis : s tudies u tilizing a rchaeological s pecimens f rom P eru i bid 4 9 9 7-115

G ilbert R .I . ( 1975 ) T race E lement A nalyses o f T hree S keletal A merindian Populations a t D ickson Mounds U npublished P hD d issertation, U niversity o f M innesota. G ilbert R .I . ( 1977 ) A pplication o f T race E lement R esearch t o P roblems i n A rchaeology . I n R .L .Blakely ( ed) P iocultural A daptation i n P rehistoric A merica U niversity o f G eorgia P ress, A thens, U SA G reen C . &R ollo-Smith S . ( 1984 ) T he e xcavation o f e ighteen r ound b arrows n ear S hrewton, W iltshire P roc.Prehist.Soc. 5 0 2 55-318 H atch J .W . &G eidel P .A. ( 1985) S tatus-specific d ietary v ariation i n t wo w orld c ultures J .Human E vol. 1 4 4 69-76 L ambert J . 13 . , S zpunar C .B . &B uikstra J .E . ( 1979) C hemical a nalysis o f excavated h uman b one f rom Middle a nd L ate Woodland s ites A rchaeometry 2 1 1 15-29 L ambert J .B ., Vlasak S .M., T hometz A .C . & P uikstra J .E . ( 1982) c omparative s tudy o f t he c hemical a nalysis o f r ibs a nd f emurs w oodland p opulations A mer.J.Phys.Anthropol. 5 9 2 89-94

A i n

L ambert J .B ., Vlasak S .M., B uikstra J .F . &C harles D .K . ( 1984 ) A nalysis o f s oils a ssociated w ith Woodland b urials . I n J .P .Lambert ( ed) A rchaeological C hemistry I II A d . i n C hemistry S eries, 2 05 . A merican C hemical S ociety , W ashington D .0 9 7-113

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L ambert J .B ., Vlasak S ., S zpunar C .B . & B uikstra J .E . ( 1985) d iagenesis a nd d ietary a nalysis J .Human E vol . 1 4 4 77-82 M ercer R .

( 1980)

H ambledon H ill

B one

E dinburgh U niversity P ress

N elson B .K ., D eNiro M .J ., S choeninger M .J ., D e P aolo D .J . & H are P .E . ( 1986 ) E ffects o f d iagenesis o n s trontium , c arbon , n itrogen a nd o xygen c oncentration a nd i sotopic c omposition o f b one Geochim .Cosmochim A cta 5 0 1 941-9 P arker R .B. & Toots H . ( 1980) T race elements i n b ones a s p aleobiological i ndicators . I n A .K .Behrensmeyer & A .P .Hill ( eds ) F ossils i n t he M aking 1 97-207 P arwell A ., R ajhage R . &W ickman F .E . ( 1957 ) N atural v ariations i n t he r elative a bundances o f t he n itrogen i sotopes Geochim .Cosmochim A cta 1 1 1 65-70 P itt-Rivers A . ( 1898) E xcavations i n C ranbourne C hase . vol 4 L ondon, P rivately P rinted P rice T .D ., S choeninger M .J . &A rmelagos C .J . a nd p ast b ehaviour: a n o verview J .Human E vol.

( 1985) 1 4

B one c hemistry 4 19-47

R heingold A .L ., H ues S . &C ohen M .N . ( 1983 ) S trontium a nd z inc c ontent i n b ones a s a n i ndication o f d iet J .Chem .Ed. 6 0 2 33-4 Runia L .T . ( 1987) Analysis of bone f rom t he Bronze Age s ite B ouenkarspel-Het V alkje, t he N etherlands A rchaeometry 2 9 2 21-32 S choeninger M .J . ( 1979) D iet a nd s tatus empirical and technical aspects of Amer.J.Phys.Anthropol. 5 1 2 95-310

o f C halcatzingo : s ome strontium analysis

S choeninger M .J ., D eNiro M .J . & Tauber H . ( 1983 ) S table i sotope r atios o f b one c ollagen r eflect marine a nd t errestrial c omponents o f p rehistoric h uman d iet S cience 2 20 1 381-3 S mith B .N . & E pstein S . ( 1971 ) Two c ategories o f h igher p lants P lant P hysiol . 4 7 3 80-4 S toll W .R . &N euman W .F . ( 1956) i ons b y h ydrated h ydroxyapatite

1 3

C / 12 C r atios f or

T he u ptake o f s odium a nd p otassium J .Amer.Chem .Soc. 7 8 1 585-8

S toll W .R . &N euman W .F . ( 1958) T he s urface c hemistry o f b one . X : t he l ack o f i nteraction b etween s odium a nd c arbonate i ons J .Phys .Chem . 6 2 3 77-9 S weeney R .E ., L iu K .K . &K aplan I .R . ( 1978 ) O ceanic n itrogen i sotopes a nd t heir u ses i n d etermining t he s ources o f s edimentary n itrogen . I n B .W .Robinson ( ed ) S table I sotopes i n t he E arth S urface 9 -26 S zpunar C .B . , L ambert J .B . & B uikstra J .E . ( 1978 ) A nalysis o f e xcavated b one b y a tomic a bsorption Amer . J . P hys . A nthropol . 4 8 1 99-202 Vlasak S .M .

( 1982 )

E lemental A nalysis o f e xcavated H uman B one :

3 79

a S tudy

o f P ost-mortem D eterioration U niversity

U npublished P hD t hesis, N orthwestern

Vogel J .C . & Van d er Merwe N .J . ( 1977) I sotopic e vidence o f e arly m aize c ultivation i n N ew Y ork S tate A mer . Antiquity 4 2 2 38-42

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F IELD T ESTS F OR M EDIEVAL D UMPS O F B LOOD A T S OUTRA , M IDLOTHIAN

B rian M offat S HARP, 3 6, H awthornvale, E dinburgh

I ntroduction a nd b ackground T he d etection o f a rchaeological b lood h as p rompted i nterest f rom t ime t o t ime, b ut t he a ppearance o f a b rief a rticle b y L oy i n 1 983 h as b een f ollowed b y as eries o f p apers over t he l ast f ew y ears ( Bahn, 1 987; G urfinkel, 1 987; G urfinkel & F ranklin, 1 988; L oy 1 987; N elson e t a l, 1 986). C oupled w ith c ontinuing f orensic d evelopments w ithin a rchaeological i nvestigations ( see B oddington e t a l, 1 987 ) a nd s pecific a dvances s uch a s " DNA f ingerprints" ( Gill e t a l, 1 985 ) a pplied t o 2 400y ear o ld m ummies ( Pgibo , 1 985 ) a nd " Lindow M an" ( Connolly e t a l, 1 986 ), t his s ubject a rea s eems s et t o g row s till f urther . I n a s ummary o f h is i nvestigations , L oy ( 1983 ) i ndicated t hat 9 0 o f t he 1 04 s tone t ools h e h ad e xamined s howed " definite s urface b lood d eposits" . A l t hough t he c riteria b y w hich t he t ools w ere s elected f or e xamination w ere n ot g iven, t hey w ere o f d iverse t ypes o f s tone, c ame f rom w idespread o rigins ( " from o pen-air s ites a long t he w est c oast a nd i n t he n orthern b oreal f orest t o C anada" ) a nd d ifferent d ates ( from 6 000 t o 1 000 y ears o ld ) a nd t his d oes s uggest t hat t he t echnique h as a w ide a pplicability a nd h olds g eneral p romise . H owever, t he s even s tages i n L oy 's l aboratory p rocedures h ave y et t o b e d escribed i n f ull . G urfinkel a nd F ranklin ( 1988) h ave a ttempted t o a ssess t he r eproducibility o f L oy 's r esults . More t han t hat , t hey h ave s et t hemselves t o a ssess a lternative e xperimental p rocedures, w ithin a p roper ( and s teadying ) i nvestigative f ramework . T hey p ropose a s et o f t hree c riteria b y w hich a ssessment i s m ade o f t heir ( or a ny ) b loodd etection p rocedure: 1 .

s ensitivity ( b lood i s o nly l ikely t o b e p resent i n t race a mounts )

2 .

s pecificity ( the t est m ust n ot g ive p ositive r esults w ith c ommon c onstituents o f t he e nvironment - a ny v ariants i n a nd o f s oil, s ensu u niverso )

3 .

t he a pplication o f p roper c ontrols ( the c ollateral s oils s urrounding t he a rtefact , a s w ell a s e lsewhere o n a nd o ff t he a rchaeological s ite, a re t o b e t ested )

Two c andidate r eagents f or t he d etection o f h aem , a f irst s tage i n b lood d etection, w ere e xamined f or s ensitivity a nd s pecificity b y G urfinkel a nd F ranklin . W ith a s et h aemoglobin s tandard, a r ange o f s olids ( clays , s oils e tc . ), a nd h aem-carrying p roteins o ther t han h aemoglobin, w ere t ested . T he s econd s tage, t he d etection o f b lood

3 81

p rotein , w as a chieved b y t he u se o f S DS-PAGE ( Sodium D odecyl S ulphate P olyacrylamide G el E lectrophoresis ). A s imulation e xperiment w as s et u p u sing 7 b lood-smeared s lides a s a " tool a nalogue" . 4o f t he s lides w ere b uried f or s ix w eeks a nd t he o ther 3 f or o ne y ear . T he d etection o f h aem a nd b lood p rotein o n t hese s lides a nd a ppropriate c ontrol s amples i s r eported . H owever, t he r esults a re e quivocal a nd b lood p rotein, w hich , i t m ust b e s tressed , c haracterises b lood, d oes evidently d egrade . L oy ( 1983 ) h ad s uggested t hat a m echanism i nvolving e lectrostatic i nteraction w ith c lay p articles t hat s equester t he b lood i n t he f irst 0 .1mm o f d eposit a dhering t o t he a rtefact s urface m ight o ffer p rotection f rom m icrobial a ttack a nd p revent l eaching . G urfinkel a nd F ranklin a lso r eport e vidence t hat t he b inding o f p rotein t o c lay r etards m icrobial d egradation, a nd s o i t s eems r easonable t hat a ny a rtefact s urface f orms a n i nterface a nd " shield l ayer" . T hey t ook e ncouragement f rom t heir r esults, a nd c oncluded t hat " . . . t his s uggested t hat b lood m ay i ndeed b e s ufficiently s table t o s urvive o n a rchaeological m aterial u nder c ertain c ircumstances" . T he a scertainment o f t hese c ircumstances i s , i n i tself , a c ritical r eseach a im, a nd w e a t S HARP c onsider G urfinkel a nd F ranklin 's c ontribution t o b e i nvaluable . I t i s a dvisable t hat s uch s imulation e xperiments a re c arried o ut i n a r ange o f s oil t ypes ; t ypes a ssessed b y f ormal s urvey i n t he f ield a nd b y a s oil s cientist . G urfinkel a nd F ranklin u sed o nly o ne " type" o f s oil f or t he 6 w eek a nd t he 1 y ear e xperiments . T he t ype u sed w as n ot d etermined, a nd i t m ay e ven h ave b een p articularly c onducive t o t he d egradation o f b lood . T he S outra H ospital p roject S HARP ( Soutra H ospital A rchaeoethnopharmacological R esearch P roject ) w as s et u p t o i nvestigate t he p hysical r esidues o f Medieval m edical t reatments f rom t he Medieval h ospital a t S outra ( Nl ' 4 53584), 2 5 k m s outheast o f E dinburgh . T he s ite o ccupies a h illtop p lateau ( above t he 3 60m c ontour ) a nd t he p resence o f t he h ospital c omplex - o f w hich t here i s n o v isible t race o n t he g round - h as b een c onfirmed b y a erial p hotographs a nd a r esistivity s urvey o f t he e ntire a rea, e xecuted b y G eoscan ( see f igure 1 ) . T his s urvey p rovided u s w ith a d etailed p lan o f n umerous l ow-resistivity f eatures . E xcavation ( August/September 1 987 ) h as d emonstrated t hat t hese a re d itches, d rains a nd p its, i nterlaced a mongst a c omplex o f w all b ases . T he d eposits i n a nd a round t he i nfirmary w ould , w e c alculate , c ontain " infirmary w aste" a nd w e h ave r eviewed a nd a nalysed w hat m ade u p i nfirmary w aste a t g reat l ength i n o ur f irst r eport , S HARP P RACTICE 1 ( 1986 ). W e r eckoned t hat o nly t hree c onstituents w ould b e d istinctive a nd v oluminous - 1 ) b lood , f rom b lood-letting p ractices , i n p articular 2 ) l evels o f l ead , w ith l ead f rom a r ange o f c ommon l ead-based a nd l eada dulterated m edicinal p reparations e nhancing t he b ase l ead l evels f rom t he e nvironment a nd h ousehold m aterial 3 ) a r ange o f e xotic p lant materials . We d iscounted a rtefacts a s a n i mportant s ource o f i nformation b ecause ' medical a rtefacts ' ( e .g Medieval p ottery a nd g lassware o r a ny f abrics o r f ibres u sed i n d ressings ) d o n ot, a t t he p resent s tate o f k nowledge , i ndicate u nambivalently t he p ractice a nd p ractices o f m edicine .

3 82

T here w as a M edieval s everal p urposes -

c onsensus o n t he v alue o f b lood-letting f or

1 ) t herapeutic - i n t he c ourse o f t reatment o f m any i llnesses 2 ) d iagnostic- i n t he c ourse o f d iagnosing i llness f rom t he c ondition o f t he b lood 3 ) r outine a nd r egulative - i n t hat a l ife-long r egimen o f b lood-letting i s u ndertaken, u nless p recluded b y t he e xtremes o f f eebleness a nd i llness . T his i s b est e xpressed b y aM edieval a ppraisal o f b lood-letting: ' It c ontains t he b eginning o f h ealth, i t m akes t he m ind s incere, i t a ids t he m emory , i t p urges t he b rain , i t r eforms t he b ladder, i t w arms t he m arrow , i t o pens t he h earing, i t c hecks t he t ears, i t r emoves n ausea, i t b enefits t he s tomach , i t i nvites d igestion , i t e vokes t he v oice, i t b uilds u p t he s ense, i t m oves t he b owels, i t e nriches s leep , i t r emoves a nxiety, i t n ourishes g ood h ealth . . . 'a nd s o o n ( from T horndike, 1 923 ). S uch e xtravagant c laims i ndicate t he c onsensus v iew , a nd c ontrai ndications a re e xtremely r are . O ne t ype o f b lood-letting , w hen u sed f or ' routine a nd r egulative ' p urposes , a llows a c alculation t o b e m ade o f t he b lood t hat w ould h ave b een l et u nder t he r ules f or r unning t he A ugustinian h ouse a t S outra . R esident p opulation

P eriod o f o ccupation

3 0

3 00 y ears

F requency o f b lood-letting x

7 -12 t imes p er y ear

V olume o f b lood l et x

3 -4 p ints

2 99,250 p ints T his i s a r ock-bottom , c onservative e stimate a nd, g iven S outra 's p osition o n am ain r oad, m ultiplying i t b y 3 , 5o r 1 0 w ould n ot b e f anciful! S outra w as s ited o n ap lateau w ithout a ny r eady m eans o f w aste d isposal w ithin 2 t o 3 km , a nd i t i s e vident t hat d igging , f illing a nd s ealing p its w ith i nfirmary w aste w ould h ave b een t he o nly m eans o f i ts d isposal . W e c an d iscount i ts u se o n l and , c omposted o r n ot , a s t here w ere s pecific p rohibitions i n t he S tatutes o f t he S cottish C hurch a gainst e ating f owl o r p igs f ed d irectly o r i ndirectly o n h uman b lood . W e k now n o p articular m eans o f d isposing o f b lood, e ither w ith r espectful c hurch c eremonial o r w ith u tilitarian d isregard f or i ts o rigins , o ther t han b urying i t i n p its . T herefore h uman b lood , p robably l et i n t he i nfirmary b y v enesection ( vein-cutting ), w ould h ave b een a m ajor i tem o f i ts w aste a nd a P rogramme t o i nvestigate f or b lood w as s et i nto t he e xcavation o f 1 987 . ( SHARP 1 988 i s t he s ource o f t he a bbreviated r eport g iven a bove , a ll s ources a re f ully d ocumented a nd j ustified t here . M offat ( 1988 ) g ives a b rief u pdate ).

3 83

e l

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3 84

e i ( D

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I nvestigations i n t he f ield a t S outra T he a rea t o t he n orth s ide o f t he c hurch ( and i ts s outhward a djunct t he b urial g round ), a nd a longside t he a xis o f t he m ain r oad ( underlying t he p resent-day m inor r oad ), p romised a n " infirmary a rea" . An a nnexed b uilding w ith a ccess t o t he r oad w as f easible t here . 1 2 t renches w ere d ug t o c onfirm t he r esults o f t he r esistivity s urvey , a ll t ransecting h igh- a nd l ow-resistivity f eatures . A l oose r ubble i nfill h ad b een u sed t o l andscape t he s ite f or a gricultural p urposes, b ut a ll d eposits u nderlying t his i nfill w ere c losely e xamined . O nce a p lan a nd s ection d rawing h ad b een a greed w ith t he A rchaeological D irector, t he a reas o f s ealed p rimary d eposits w ere i dentified i n a greement w ith t he Director o f E xcavations, G ordon E wart, a nd s oil s cientist, D avid J ordan . E xtensions t o t he t renches w ith p rimary d eposits w ere c ut, a nd e ven h oriz vtal s lices w ere t aken a t 0 .15m l evels . G rids b ased o n 0 .15 x 0 .15 m ' w ere o verlaid . At t his s tage t he d eposits b ecame e asier t o i nterpret, a nd t wo d istinct t ypes o f d eposit b ecame evident . O ne w as t he s ubstrate ( an o chre-yellow/brown c lay ) a nd t he o ther w as a c omplex i nfill o f c uts i nto t he s ubstrate. Deposit 1

o chre-yellow/brown c lay

D eposit 2 d ark b rown/purplish b rown l oamy c lay

C obbles, p ebbles, g ravel a nd g rit o f i rregular f orm a nd w ear, p lus c oal, r ed a nd y ellow s andstone a nd g reywackes , a re a ll c ommon t o b oth d eposits a nd c an b e s een w ith t he n aked e ye o r a t 1 0x, 4 0x a nd 1 00x w ith a p etrographic m icroscope. S HARP 's n otion o f ' infirmary w aste ' w as t hen i nvestigated t hrough 1 ) d eterminations o f l ead 2 ) i dentification o f ( any ) e xotic plant m aterial a nd 3 ) s pot-tests f or b lood . L ead d eterminations w ere m ade b y a tomic a bsorption s pectrophotometry ( AAS ) a nd t he r esults w ere i n 2 3 s quares w holly w ithin D eposit 1 l ead v alues r ange f rom 3 2 t o 1 50 p pm

i n 2 2 s quares w holly w ithin D eposit 2 l ead v alues r ange f rom 1 70 t o 1 510 p pm

I n t he a bsence o f i dentifiable p lant m acroremains , t he g ridded s tudy a rea ( figure 2 ) w as a nalysed f or p ollen. D eposit 1 c arried n o p ollen . D eposit 2 h ad : - M yrtle f amily ( Myrtaceae ) 6 4 g rains M ugwort g enus ( Artemisia ) 1 6 g rains R ibwort 3g rains C omposites w ith " latex" 3g rains N o r ecords o f p ollen f rom t he M yrtle f amily h ave b een f ormally r eported f rom a rchaeological s ites i n B ritain . T wo g enera o f t he f amily a re n ow l isted a s g rowing i n E urope - E ucalyptus a nd Myrtica . E ucalyptus o r ' gum ' t rees a re a n e xclusively A ustralasian g enus a nd s everal s pecies h ave b een i mported i nto E urope f or o rnamental p urposes . H owever, a s t his t rade o nly b egan l ast c entury t he p resence o f E ucalyptus a t S outra i n t he M edieval p eriod c an b e d iscounted . T he Myrtica g enus i n E urope c omprises o ne s pecies a nd t wo s ub-species a nd i s t he e vergreen,

3 85

a romatic s hrub o r s mall t ree - m yrtle. A s a n o rnamental s hrub a nd a s ource o f a romatic e ssential o il, i t h as b een w idely t ransplanted t o n orthern E urope f rom i ts M editerranean r ange o f d istribution . B ut t here i s n o r ecord o f t he w idespread a nd c ommonplace c ommerce i n m yrtle i n m edieval t imes . I n c ontrast t here i s v oluminous e vidence f or m edieval t rade i n t he s pice c loves , a n on-European m ember o f t he m yrtle f amily ( Eugenia c aryophyllus ). I t i s l isted a mong t he d ozen o r s o s pices t hat a re i n c ommonplace u se i n t he m edieval m onastic h ousehold ( this i s d iscussed f urther, w ith f ull h istorical d ocumentation, i n S HARP P ractice land 2 ). T he f inal d iagnostic f actor t o b e e xamined w as t he p resence o f b lood . Many k its f or t he d etection o f b lood a re available, a nd t hese a re p roven a nd w ell-tried . T rade-marked p roducts a re i n e veryday u se i n t he d etection o f i nternal b leeding ( gastro-intestinal, c ob -rectal a nd i n u rinalysis ) a nd i n f orensic s cience . I t i s t herefore w orth g iving a b rief d escription o f s ome c ommercially a vailable t est-kits t hat m ight h ave a n a rchaeological a pplication. TAsts f or t he d etection o f b lood:

t heir a pplication

W e m ade e nquiries a s t o t he p harmaceutical t ests u sed f or t he d etection o f c oncealed b lood i n f aeces . A ll h ad n ecessarily b een evaluated p harmacologically i n a dvance o f t heir u se i n t he N ational H ealth S ervice, w here t hey a re e stablished a s p reliminary d iagnostic m easures i n t he d etermination o f i nternal b leeding - p articularly i n t he e arly s tages o f b owel c ancer . T he t ests u sed w ere H aemoccult tm t est e nvelopes , H aemoccult tm t ape a nd C oloscreen/VPI tm t est e nvelopes . T he m anufacturers a nd t he l icensed a gents f or t hese p roducts k new o f n o p revious a rchaeological u sage, a nd p rovided S HARP w ith s cientific j ustification f or t heir p roducts a nd i nstructions f or t heir u se . A ll t hree t ests ( setting a side t he V PI c omponent o f t he l ast o ne ) a re b ased o n t he u se o f p aper i mpregnated w ith g uaiac . G uaiac i s t he p urified e xtract o f G uaiacum o fficinale ( or L ignum v itae ), a t ree n ative t o M esoamerica . G uaiac p aper t ests a re b ased o n t he o xidation o f p henolic c ompounds ( i .e g uaiaconic a cids ) p resent i n t he g uaiac b y c ombination w ith t he h aemoglobin f raction i n t he b lood . T his o xidation p roduces a d istinctive b lue c olour w hich a ppears w hen a s ample c ontaining b lood i s p ut o nto t he t est p aper, a f luid r eagent a pplied a nd c ontact i s m ade b etween t he h aemoglobin a nd t he g uaiac . B oth H aemoccult tm p roducts c omprise s imply t he a pplication o f t he s uspect s ample t o o ne s ide o f t he i mpregnated p aper a nd t he a ddition o f t wo d rops o f t he s tabilised h ydrogen p eroxide d eveloper s olution t o t he o ther ( see f igure 3 ). T he r eaction t akes p lace a t 3 0 s econds, a fter w hich b lue w ill t inge t he c o-extensive s ample a nd d eveloper. A s ensitivity o f t he o rder o f 1 p art b lood i n 5 000 p arts f aeces i s c laimed f or H aemoccult , a nd s cientific d ata q uoted b y t he m anufacturers s uggest t hat t his p roduct i s s uperior t o m any o thers b ecause i t g ives o nly a ' false p ositive ' o f a round 1 2% a s c ompared w ith r ates over 7 0% t hat a re s ometimes a chieved w ith o ther p roducts . T he s ource o f t hese ' false p ositives ' i n f aecal a nalysis i s s aid t o b e " other p eroxidases i n t he s tool" .

3 86

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F igure 5 . T otal i on c hromatogram o bserved f or C MG 9 5 , l ining f rom D ressel 2 -4 a mphora, C aerleon.

y ellow p owdered

c is-abienol, a nd, a lthough t his c ompound i s q uickly o xidised, c haracteristic d egradation p roducts s hould s till b e d etectable i n d egraded s amples ( Mills & W hite , 1 977 ). N one o f t hese d egraded p roducts i s v isible i n o ur s amples , b ut e ach s ample i s c urrently b eing s creened s pecifically f or t races o f d egraded a bienol . L arch r esins a lso c ontain n eutral c ompounds i n a ddition t o r esin a cids a nd o ne , k nown a s l arixyl a cetate, i s r elatively s table a nd s hould b e p resent i n e ven a ged s amples. F igure 5 s hows t he c hromatogram r ecorded f or C MG 9 5 , aD ressel 2 -4 a mphora s herd w ith r esinous m aterial e xcavated f rom a w ell a t C aerleon . T he t race c onfirms t he a bundance o f m ethyl d ehydroabietate, w ith s maller q uantities o f m ethyl 7 -oxodehydroabietate . S ome o f t he d ehydroabietic a cid i n t he s ample h as b een f urther d ehydrogenated y ielding a t race o f m ethyl 1 3-iso-propy1-5tK podocarpa 6 ,8,11,13 t etra-16-enoate . N o d ecarboxylation h as t aken p lace a nd t his i ndicates t hat a ny d egradation, e ither t hermal o r m icrobial, h as b een m inimal. T he s pecific l ack o f t hermal d egradation i s i ndicated b y t he a bsence o f

4 38

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tetraen-16-oate (6)

Figure 6. Diterpenoid constituents of resinous materia l from Rhodian amphora , Caerleon . Rela tive abundances-given in brackets

discolouration in the sample and confirmed by the preservation of unaltered resin acids - abietic, pimaric and isopimaric. The equal proportions of the latter two acids in the sample relates to their distribution in Pinus pinaster, the European pine common to much of the Mediterranean area. The distinctive fabric of this amphora sherd, (identified by E.Campbel1), can be pinpointed to the granitic areas around Barcelona, a region producing a fine wine in antiquity (Williams, 1985 p.160). The Rhodian amphora resin from Caerleon has a similar physical appearance to the sealant associated with the Northern Spanish Dressel 2-4 amphora. The fabric belongs to Peacock's no.l (Peacock, 1977), the most common amphora type imported into Britain. The structures of the comfX)unds identified are given in figure 6, with relative abundances shown in brackets. The presence of the hydrocarbons norsimonellite and retene may indicate degradation of precursor acids, although traces of these compounds are known to be present in fresh oleoresins (Simoneit et al, 1986). The samples collected from the Museum of London amphora reference collection generally s how similar chromatograms to those described above, although there is wider range and larger proportion of oxidised resin acids. This may be explained by the storage of these vessels for many decades in the museum, as this is likely to have promoted autoxidation of previously unaltered acids. Each sample tends to

consist of a curious suite of unal tered , dehydrogenated and decarboxylated resin acids. Figure 7 shows the trace given by Ex.GM, a Camulodunum 185A amphora. The principal cornmodity transp:>rted in these vessels rnay have been defrutum, a syrup prepared by boiling down grape­ rnust (Sealey, 1985 p.62- 4). The mixture of unaltered and degraded cornp:>nents rnay have resulted frorn the greater exp:>sure of outer layers to rnicrobial action . The Carnulodunurn 189 or 'carrot' arnphora frorn Canterbury is described by Arthur (1986 p. 253). The forro is a true 'carrot' type and not a larger Kingholrn 117 wi th which it rnay be confused (see Sea ley, 1985 p.87-91 for a good discussion). The capaci ty of these vessels at around 3 litres is rnuch less than those of the other arnphora types irnported in the 1st and 2nd centuries AD. The contents and provenance of these vessels rernains speculative, although a fruit, possibly dried (such as dates) is often ci ted as the possible cornrnodi ty transported frorn the Eastern Mediterranean or North Africa. The rather fragrnentary evidence on which this idea is based is discussed by Sealey (1985). An internal resinous sealant has not previously been reportea frorn a Carnulodunurn 189 arnphora, and this finding �ay therefore not be representative. However, these vessels have not yet·been recovered frorn wreck sites and it is rnainl y rnaterial frorn wrecks that has so far been exarnined for the presence of sealants. Dehydroabietic acid is the roa.in compound identified in the sample, although the fully degraded arornatic hydrocarbon retene is also present i n sorne quantity (Peak intensity 62 as per centage of rnethyl dehydroabietate). This indicates a more heated, resinous rnater ial as would be expected from the preparation of pitch. The rernaining compound detected is a trace of 7-oxodehydroabietic acid. Mills and White (1977 p.24) have suggested that the absence of this oxidation product in aged resins rnight indicate that the resin was heated in antiquity. However, the presence or absence of this oxidation product is rore likely to be associated with the type of burial environrnent. Strongly reducing environrnents contribute to the forrnation of arornatic diterpenes frorn resin acid precursors, whereas in oxygenated systerns it is expected that oxidised resin acids will be present (Barnes & Barnes, 1983). Dehydoabietic acid has been detected in one of the vessels sampled frorn Usk (context LBC 1), but this is a fragrnentary piece and it has not been p:>ssible on the basis of body sherds to determine whether it is a Kingsholrn 117 arnphora. The contents of 'true' Carnalodurnurn 189 amphoras rnay have to be re-examined in the light of current evidence. Dates have been found in Kingsholrn 117 amphoras frorn the late 1st century BC wreck of La Tradeli�re (Fiori & Joncheray, 1975 p. 62) and figs have been recovered frorn Rhodian arnphoras frorn the Drarnont D shipwreck (Joncheray, 1973 26-7). These two arnphora types have a greater capacity than the dirninutive C 189 arnphoras. It rnay be argued that the 'carrot' arnphoras represented a high quality fruit product originating frorn a specific region, or that a more luxur ious product was carried in these vessels; an unguent or per fume, for exam ple, rather than a foodstuff. The very low yield of extractable organic material given by arnphora sherds frorn the Usk assernblage necessitates the destruction of large ,1pl�s, usual 1 y 5-20 g, in order to recover rnilligram quantities of :j·: .•

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S C R T I T I M E

F igure 7 . T otal i on c hromatogram g iven b y r esinous m aterial f rom C amulodunum 1 85A a mphora, L ondon .

r esidue . I n s ome r are c ases h owever, i t h as p roved p ossible t o r ecover s ubstantial o il o r r esinous r esidues f rom a mphora f abrics . I t i s w ise t o c onsider c ontrol s ampling i n o rder t o p resent c omparative i nformation a nd t o v alidate r esults t o a n u nderstandably c autious a rchaeological c ommunity . W e h ave f ound t hat s ampling a mphora h andles , u nlikely t o h ave c ome i nto c ontact w ith l inings o r c ontents, t o b e p articularly u seful i n t his c ontext , t o a ssess b ackground l evels f rom , f or e xample, t he m igration o f o rganics f rom t he s oil m atrix . I t i s u ndoubtedly n aive t o s uggest t hat t here w ill b e n o i nterference o r c ontamination f rom t he b urial e nvironment . T otal i on c hromatograms o f m ethylated e xtracts o ften s how p oorly r esolved a nd c omplex t races . E ven s o, t he r ecent u se o f c ombined g as c hromatography-mass s pectrometry a llows t he p ossibility t o s creen t he m ixture f or t he p resence o f p articular c ompounds , u sing a t echnique k nown a s m ass f ragmentography . F igure 8 d emonstrates t he u se o f t his f acility t o h ighlight t he p resence o f m ethyl d ehydroabietate f rom a D ressel 3 0 a mphora s herd ( context L AR 1 . ). F igure 8 A g ives t he t otal i on c hromatogram , w hile 8 B a nd 8 C s can o nly f or t he p tesence o f t he s elected i ons 3 14 a nd 2 39 r espectively , t he m olecular i on a nd b ase p eak o bserved i n am ass s pectrum o f m ethyl d ehydroabietate . A m ass s pectrum o f t he p eak o ccurring a t m ass s can 8 82 a llows t he i dentification o f m ethyl

4 41

2

R elative

3 8

Abundance

S can

B - m/t 3 14

1 8_

C - m/L

2 39

F igure 8 . A ) t otal i on c hromatogram g iven b y m ethylated e xtract f rom D ressel 3 0 a mphora, U sk B ) s elected i on s can f or m /z 3 14 C ) s elected i on s can f or m /z 2 39 .

4 42

d ehydroabietate . F igure 8 B a lso d etects a c omponent a t m ass s can 9 94 a s m ethyl 7 -oxodehydroabietate . I t i s e ncouraging t o n ote t hat a s ample f rom t he h andle o f t he s ame v essel d id n ot s how a ny t race o f e ither o f t he a bove c ompounds w hen a nalysed b y m ass f ragmentography . C onclusions G enerally , t he v isibly p reserved l inings f rom t he a mphoras s tudied a re m ore c losely r elated t o d egraded r osin t han w ood t ar o r p itch . T he l atter w ould b e e xpected t o c ontain n o u naltered r esin a cids a nd a m ore c omplex r ange o f d egraded d iterpenoid h ydrocarbons i n g reater q uantities t han d etected h ere . T wo s amples ( Camulodunum 1 89 a nd ? A fricana 2 A ) c ould b e i nterpreted a s w ood p itch s ince n o p recursor r esin a cids s urvive , a lthough t his m ay b e d ependent o n t he p articular b urial e nvironment . H owever, t here i s e vidence t o s uggest t hat a r igid d istinction b etween r esin a nd p itch m ay b e i llusory . T he w ood p iles o r t umuli c onstructed t o p repare p itch p robably y ielded l arge q uantities o f p ix l iquida, b asically w arm l iquified r esin, b efore t emperatures w ere h igh e nough t o p yrolyse a nd t hermally d egrade c onstituent r esin a cids . A ccording t o P liny , t he r esinous m aterial i nitially ' flows l ike w ater d own a p ipe ' f rom t he p itch ovens ( Nat .f lis 1 6.21.52). T heophrastus r ecords t hat i t w as t his m aterial t hat w as u sed t o f lavour a nd p reserve w ines . S ince w ine i s f lavoured w ith t he v olatile c omponent o f r esins, i t c an b e a ssumed t hat t his m aterial w as r eleased a t l ow t emperatures . S ignificantly , t he p itch-oven r eceiver v essel a t L e S apey c ontained a y ellow o dorous r esin a nd n ot a b lackened w ood t ar. I t i s p robable t hat t he r elatively l ow y ield o f t apped o leoresin c ould n ot h ave a ccommodated t he l arge n umbers o f a mphoras r equiring a s ealant . T he p itch o ven a llowed t he c ollection o f l arge q uantities o f m aterial f rom o ne s ite , a nd a lthough t his h arvesting w ould h ave b een d estructive o f t he w ood, c onifers c an r egenerate q uite q uickly . T his i nterpretation r econciles t he d ocumentary e vidence, t hat ' pitch ' w as u sed f or t he l ining o f c eramic c ontainers w ith t he a nalytical e vidence w hich s uggests t hat t he l inings a re p redominantly d egraded r osins . E vidence s uggests t hat t he p ractice o f s ealing a mphoras w ith a n i nternal l ining w as w idespread . I t s hould b e c onsidered t hat e ven i f s olid o rganic p roducts w ere t ransported i n a mphoras, p roducts l ike o lives , f ruit a nd f ish p roducts , t hey w ere r egularly b ottled i n l iquid m edia s uch a s o ne o f t he m any v arieties o f w ine , v inegar, d efrutum a nd o live o il; a ll e xcept t he l atter r equiring t he a pplication o f a n i nternal v essel l ining ; F or e xample , t he P an S and a mphora d escribed b y S ealey ( 1985 p .167 ), a nd f ound t o c ontain o ver 6 ,000 o live p its , s howed t he p resence o f a n i nternal s ealant . E vidence s uggests t hat t he o lives w ere o riginally p reserved a nd t ransported i n d efrutum ( Sealey & T yers , f orthcoming ). T he p ossibility t hat r esinous l inings o r d eposits i n v essels a re t he r emains o f r esin-flavoured b everages o r ' retzinas ' h as b een r aised o n m any o ccasions . T he a ddition o f r esin t o w ine i n o rder t o s eason, f lavour a nd p reserve t he v intage w as a w ell k nown p rocedure i n a ntiquity, a nd m odern G reek ' retzinas ' a re p repared i n t his w ay w ith t he a ddition o f f resh p ine o leoresin t o t he m ust p rior t o o r d uring f ermentation . I t i s t he v olatile o il i n t he o leoresin w hich g ives t he w ine i ts f lavour . White ( in C astle, 1 978) a nd S hackley ( 1982 ) a re s ceptical t hat t he r esinous m aterials t hat t hey i dentified a re r esidues

4 43

o f r esinous w ine, w hilst A ddeo e t a l ( 1979 ) a ppear c ertain t hat t he r esins t hey s tudied f rom i st c entury B C a mphoras f rom O plonti a re j ust t hat . C learly t he y ellow d eposits i nterpreted b y J ongkees ( 1955 ) a s p recipitated w ine r esidues a re n ot t hat b ut a re r emains o f a n i nternal s ealant n ot s ubject t o h eating i n a ntiquity . L ucas ( quoted i n C ockle, 1 981 ) o bserved t hat w ine s tored o r t ransported i n a mphoras l ined w ith r esin w ould a cquire a s light r esinated t aste . T his i nterpretation h owever a ssumes t hat s ome v olatile o il r emained i n t he r esin w hen t he w ine w as d ecanted i nto t he v essel . T his s tudy h as d emonstrated t hat R oman t ransport a mphoras w ere c ommonly l ined w ith r esinous m aterials d erived f rom c onifers , m ost p robably p ine . Any d eviations f rom t his i dentification m ay o ffer i nteresting p ossibilities w ith r espect t o p rovenance a nd/or c ontents . T he p hysical n ature o f t he l inings m ay v ary f rom p owdery y ellow d eposits t o t hick, b lack a ngular m aterials . D ehydroabietic a cid i s u sually t he m ain c omponent, a lthough o ne e xtract f rom a D ressel 2 -4 ' black s and ' a mphora f rom U sk i s e nriched i n 7 -oxodehydroabietic a cid . T he p rimary f unction o f t he l inings s eems t o b e t he p rotection o f t he c ontents t hrough t he p rovision o f a n i mpervious l ayer o ver t he e ntire i nternal s urface o f t he a mphora, a lthough a s econdary f unction, i .e . t he f lavouring o f w ine , c annot b e f ully d iscounted . I t i s p ossible t hat t he y ellow p owdered l inings , n ever s ubject t o i ntense h eat , r etained a v olatile c omponent t hat m ay h ave c ontributed t o r esinating w ine c arried i n t hese a mphoras . T he a ssociation o f r esins, t ars a nd p itches w ith a rchaeological c eramics m ay r elate t o a r ange o f a lternative f unctions n ot m entioned h ere, a nd a nalysis o f n atural p roducts m ay h elp t o e lucidate v essel u sage o n aw ider s cale . A cknowledgments T he a uthors a re g rateful t o t he Museum o f L ondon, C anterbury A rchaeological T rust , N ewport C ounty Museum a nd t he G lamorgan-Gwent A rchaeological T rust f or p ermission t o t ake s amples , a nd t o i ndividuals w ho a ssisted i n t heir a cquisition , B eth R ichardson , A ndrew S avage , D ave Z inkiewiez, B ob T rett a nd E dith E vans . We w ould a lso l ike t o t hank P rofessor W .H.Manning f or permission t o s tudy t he Usk a mphora a ssemblage a nd P aul S ealey , E wan C ampbell a nd A ndreas D anopoulos f or u seful d iscussion. The a uthors would also l ike t o t hank D r J .A .Ballantine a nd t he S ERC Mass Spectrometry S ervice, S wansea, f or r unning t he G C-MS s amples . B eryl B arnes t yped t he m anuscript w ith s peed a nd e fficiency . W hilst R ichard E vershed k indly c orrected a n e arlier d raft o f t his p aper, a ny e rrors r emain o ur o wn. R EFERENCES A ddeo F ., B arlotti L ., B offa G ., D iLuccia A ., Malorni A ., & R icci° G . ( 1979 ) C onstituenti a cidi d i u na o leoresina d i c onifere r invenuta i n anfore vinarie d urante gli s cavi a rchaeologici d i Oplonti A nn.Fac.Sci.Agrar.Uni.Studi.Napoli, P ortici 1 3 1 44-8 A rnold D .E . ( 1985 ) U niversity P ress A rthur P . 9 39-58

( 1986)

C eramic T heory a nd C ultural P rocess

R oman a mphoras f rom C anterbury

4 44

C ambridge

B ritannia

1 7

B alsan L . ( 1951 ) L 'industrie d e l a r esine d ans l es C ausses e t s on e xtension d ans l 'empire R oman G allia 9 5 3-5 B arnes M .A . & B arnes W .C . ( 1983) d iterpenes i n l acustrine s ediments 2 89-98

O xic a nd a noxic d iagenesis o f A dvances O rganic G eochem . 1 981

B enoit F . G allia 1 2

( 1954) p .47

Amphores e t c 6ramique d e l ' eave d e Marseille

B leck R .D . 2 04-8

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9

B oyer R . ( 1986 ) C onserve d 'olives d ans d eux a mphores t rouv6es d ans l es f ouilles d e l a B ourse, f rMarseille G allia 4 4(2 ) 2 29-33 B randt J . ( 1960 ) D as U rnengräberfeld v on P reetz i n H olstein 2 b is 4 J ahrhundert n ach C hristi G eburt. O ff a-Bucher 1 6, N eumunster C astle S .A . 3 83-92

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1 975

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B ritannia

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a n ew p apyrus

C oils D ., E tienne R ., L equement R ., L iou B ., & Mayet F . ( 1977) L ' eave P ort Vendres I I e t l e C ommerce d e l a B etique ä 116 poque d e C laude A rchaeonautia 1 C ondamin J . S tF ormenti F . ( 1978) D etection d u c ontenu d 'amphores a ntiques ( huiles v in ): e tude m ethodologique R evue d 'Archaeometrie 2 4 3-58 C ondamin J ., F ormenti F ., Metais M .O ., M ichel M . &B lond P . ( 1976) T he a pplication o f g as c hromatography t o t he t racing o f o il i n a ncient a mphorae A rchaeometry 1 8(2 ) 1 95-201 Evershed R .P ., J erman K . &E glinton G . p itch f rom t he M ary R ose N ature 3 14 F iori P . & J oncheray J -P d e F ouille s ur repave S ubaquatique 4 5 9-70

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P ine w ood o rigin f or

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F ormenti F ., H esnard A . & T chernia A . ( 1978) N ore s ur l e c ontenu d 'une a mphore Lamboglia 2 d e l '6pave d e la Madrague d e Giens A rcheonautica 2 9 5-110 G ibbins D .J .L . &P arker A .J . ( 1986) T he R oman w reck o f c . A D 2 00 a t P lemmiro, n ear S iracusa ( Sicily ): i nterim r eport i nt .J .Nautical A rchaeol. U nderwater E xploration 1 5(4) 2 67-304 H eron C . & P ollard A .M. ( in p rep . ) F at a nd o il d egradation i n a rchaeological c ontexts. A r ev iew .

4 45

p reservation

a nd

J oncheray J -P . ( 1973) ( campagnes 1 970-1971 )

C ontribution 1 l ' tude d e re pave D ramont D C ahiers d 'Archeologie S ubaquatique 2 9 -48

J oncheray J -P . ( 1977 ) M editerranean h ull t ypes c ompared . 2 . W reck F f rom C ape D ramont ( Var), F rance I nt .J .Nautical A rchaeol.Underwater E xploration 6 (1 ) 3 -7 J ones R .E . ( 1986 ) G reek a nd C ypriot P ottery : a r eview o f s cientific s tudies B ritish S chool a t A thens, F itch L aboratory O cc.Paper 1 Jongkees J .H . ( 1955) G allia 1 3 8 8-9 L abrousse M . 4 54-500

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i nterieür

d es

a mphores

C irconscription d e M idi-Pyrenges

r omaines

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3 2

L ange W . ( 1983) D ie U ntersuchung e ines m ittellerlichen H olzteers a us d em F und d er B remen K ogge b erliner B eit .Archaeometrie 8 2 899 8 L eglay M . 5 15-47 L ucas A. L ondon

( 1973 )

( 1948 )

C irconscription d e R ilne-Alpes

G allia

A ncient E gyptian M aterials a nd I ndustries

Mannning W .H . ( 1981) U sk . T he U niversity o f Wales P ress, C ardiff

F ortress

E xcavations

3 1

3 rd e d .

1 968-71

Meiggs R . ( 1982 ) T rees a nd T imber i n t he A ncient M editerranean W orld C larendon P ress, O xford M ills J .S . &W hite R . ( 1977 ) N atural r esins o f a rt a nd a rchaeology . Their s ources, c hemistry a nd i dentification S tud .Conservation 2 2 1 2-31 Mills J .S . & W hite R . ( 1982) O rganic m ass s pectrometry o f a rt m aterials: w ork i n p rogress N at.Gallery T ech.Bull. 6 3 -18 Mills J .S . & W hite R . ( 1987) O b jects B utterworths, L ondon N eedham S . & E vans J . ( 1987 ) r esidues f rom R unneymede B ridge

T he O rganic C hemistry o f

Museum

H oney a nd d ripping: N eolithic f ood O xford J .Archaeol. 6 (1 ) 2 1-8

O ddy W .A . & B ateman J . ( 1973 ) Analysis o f a mphora l inings I n M .J .Blackman (ed) M arine A rchaeology C olston P apers , v ol 2 3 B ristol p .381 P arker A .J . ( 1973 ) T he e vidence p rovided b y u nderwater a rchaeology f or R oman t rade i n t he W estern M editerranean i bid 3 61-81 P assi S ., R othschild-Boros M .C ., F asella P ., N azzaro-Porro M . & Whitehouse P . ( 1981 ) A n a pplication o f h igh p erformance l iquid c hromatography t o t he a nalysis o f l ipids i n a rchaeological s amples J .Lipid R esearch 2 2 7 78-84

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P eacock D .P .S . ( 1977 ) R oman a mphorae : t ypology , f abric a nd o rigins . I n G .Vallet ( ed ) M 6thodes C lassique e t M 4thodes F ormelles d ans l 'Etude d es A mphores C ollection d e l 'Ecole F rancaise d e R ome, 3 2, 2 61-78 P hilp R .P . ( 19 i 35 ) E lsevier, A msterdam R ajewski Z . A rchäologie

F ossil F uel B iomarkers :

( 1970) 4 4 6-53

P ech

u nd

t eer

b ei

a pplications a nd s pectra

d en

S lawen

Z eit .

f ür

R obinson N ., Evershed R .P ., H iggs W .J ., J erman K . & E glinton G . ( 1987 ) P roof o f t he p ine w ood o rigin f or p itch f rom T udor Mary R ose ) a nd E truscan s hipwrecks : a pplication o f a nalytical o rganic c hemistry i n a rchaeology A nalyst 1 12 6 37-44 R othschildBoros M .C . I n G .Barker & R .Hodges 1 02 7 9-89

( 1981 ) T he d etermination o f a mphora c ontents . ( eds ) A rchaeology a nd I talian S ociety 2 B AR I S

R ottländer R .C .A . ( 1986) C hemical i nvestigations o f p otsherds o f t he H euneberg, U pper D anube . I n J .S .OLin & M .J .Blackman ( eds ) P roc . 2 4th I nter.Archaeometry S ymposium 4 03-6 S ealey P .R . S heepen B AR

( 1 98 5 )

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O lives f rom R oman S pain - a

S hackley M . ( 1982 ) G as c hromatographic i dentification o f a r esinous d eposit f rom a 6 th c entury s torage j ar a nd i ts p ossible i dentification J .Archaeol.Sc. 9 3 05-6 S imoneit B .R .T . ( 1977) deep-sea sediments G eochim .Cosmochim .Acta

D iterpenoid c ompounds a nd o ther l ipids i n and their geochemical s ignificance 4 1 4 63-76

S imoneit B .R .T ., G rimalt J .0 ., Wang T .G ., C ox R .E ., H atcher P .G . N issenbaum A . ( 1986) C yclic t erpenoids o f c ontemporary r esinous plant d etritus a nd o f .f ossil woods, a mber a nd c oals A d .Organic G eochem . 1 985 1 0 8 77-89 W illiams D .F.

( 1985)

P etrology

I n S ealey 1 53-66

W illiams D .F . & P eacock D .P .S . ( 1983 ) T he i mportation o f o live o il i nto R oman B ritain . I n J .Blazquez & R emesal J . ( eds ) P rod . Y c om . d e A ceite e n L an A ntiquedad I I C ongresso M adrid 2 63-80 Z emer A .

( 1978)

S torage J ars a nd A ncient S ea T rade

4 47

H aifa

V EGECULTURE I N S OLOMON I SLANDS P REHISTORY F ROM P OTTERY R ESIDUES

H .E.Hill, D ept. o f H uman E nvironment, I nstitute o f A rchaeology , 3 1-4, G ordon S quare, L ondon W C1. a nd J .Evans, D ept. o f P hysical S ciences, N orth E ast L ondon P olytechnic, S tratford, L ondon E 15.

P ottery r esidues o n s herds f rom S anta C ruz a nd R eef I slands i n t he S outheast S olomons h ave b een a nalysed u sing c hemical m ethods t o e stablish t he p resence o f a ny p lant t races r emaining f rom s torage o r c ooking p rocesses . T his i s p art o f a c ontinuing i nvestigation i nto f inding u seful i nformation a bout t he p lants i n u se i n P acific p rehistory , a nd t hese p articular s ources o f p ottery w ere c hosen b ecause t he S olomon I slands a re a f airly c rucial a rea i n e stablishing t he m ovement o f L apita p eople i nto t he a rea o f F iji, T onga a nd S amoa o f W est P olynesia. T he a im h as b een t o f ind a s imple, r eproducible a nd c onsistently u seful a rchaeological method f or detecting t he p resence o f c haracteristic o rganic m aterials i n o r o n p ot s herds, a nd t o t est i ts u sefulness i n a pplication t o a rchaeological s amples . T o b e o f r eal v alue t he m ethod n eeds t o b e c apable o f r epetition b y o ther i nterested a rchaeologists , a nd n ot r equire e xpensive o r e laborate e quipment . T his w ould a llow i ndependent a nalysis b y o ther r esearchers, a nd a lso m eans t hat d ata c an b e o btained t hat m ight c onfirm r esults o btained b y a v ariety o f o ther, p ossibly m ore e xpensive , m ethods i n a ssociated f ields o f r esearch . A nalytical m ethod T here b eing n o i nfra-red s tandards a vailable f or t he m ain P acific c ultigens , s everal y ears w ork h as g one i nto p roducing s tandards f or a s election o f t he m ain c ultigens f rom t he a rea . T he s ix c ultigens s elected f or s tudy w ere : b anana ( Musa a ustralimusa ), s weet p otato ( Ipomoea b atatas ), r ice ( Oryza s ativa ), s ago ( Metroxylon s agu ), t aro ( Colocasia s p . ) a nd y am ( Dioscorea s p . ). T hese p articular s pecimens w ere c hosen a s i t w as f elt t hat t hey w ere r epresentative o f t he t ypes o f f ood p roduced, w hich vary a cross t he P acific, a nd would a lso b e u seful i ndicators o f m an 's s ettlement o f t he P acific . T o p roduce t he s tandards a t l east h alf a d ozen m odern s amples o f e ach p lant w ere n eeded . E ach s ample w as t hen e xtracted i n as oxhlet a pparatus . F our d ifferent s olvents w ere u sed o n e ach s ample, n amely h eptane, c hloroform , 2 -propanol a nd d istilled w ater. T his g roup o f s olvents w as u sed f or s everal r easons . F irst t hese s olvents s electively

4 49

e xtract m ost s ubstances . F or e xample, h eptane t ends t o e xtract a ny p olar l ipids , t riglycerides a nd w axes p resent ; c hloroform s eparates o ut a ny r esins, d rying o ils a nd w ood t ars ; p ropanol s eparates p hospho l ipids, s ugars, a mino a cids a nd p roteins ; a nd w ater s eparates p olar l ipids, s alts, s ugars a nd c arbohydrates ( Hill & E vans, 1 987 p .91 ). S econdly t hey a ll g ive e xtracts t hat a re p articularly u seful f or s ubsequent i nvestigations . A t hird a dvantage f rom t he a rchaeological s tandpoint i s t hat a ll f our c hemicals a re r elatively c heap . T he n on-aaueous e xtracts w ere e xamined b y at win b eam i nfra-red s pectrometer . T he s ample e xtract w as e vaporated o nto a s mall p otassium b romide ( KPr ) d isk ; t his d isk b eing n eutral t o i nfra-red l ight . A t win b eam s ystem a llows a c omparison b etween a r eference p otassium b romide d isk o n t o w hich s ome o f t he s olvent u sed f or t hat p articular e xtraction h as b een e vaporated a nd a s ample d isk w hich c ontains t he s olvent p lus w hatever h ad b een e xtracted . T he r esult i s t hat t he s pectrometer o nly i dentifies t he d ifference b etween t he t wo d isks a nd, a s t he o nly d ifference b etween t hem i s t he p resence o f t he s ample e xtract , a ny d ifferences r ecorded m ust b e p roduced b y t he e xtract . T his a ssumes t hat t here i s n o c ontamination , i f t he K Pr u sed t o p roduce t he d isks o r t he s olvent h ave b een c ontaminated i n a ny w ay t hen a t win b eam s pectometer e nsures t hat a ny c ontamination i s c ompensated f or . T he s ample e xtraction w as t hen s canned a nd d isplayed o n t he m onitor o f ad ata s tation w ith a d isk d rive a nd t he s pectra w ere s aved a nd p lotted o ut o n a c hart . D uring t he i nitial i nvestigations t he r esults f or t he t hree d ifferent e xtractions o n o ne p lant w ere c ompared , a nd a s t here w ere n o c onsistent v ariations i n w avelength o ccurrences b etween h eptane , c hloroform a nd p ropanol e xtracts t he w ork t hen c oncentrated o n o btaining a f ull r ange o f h eptane e xtracts p rocessed o ver t he 4 5 p lant s amples. T he f ourth e xtract , p roduced w ith w ater, w ould o bviously d issolve a K Br d isk a nd s o t hese e xtracts w ere k ept f or o ther a nalyses s uch a s t hose f or s ugar. T he s ame c hemical t echniques u sed f or p roducing t he s tandards w ere u sed t o a nalyse r esidues o n a ncient p ottery a nd, t hereby , p ossibly i dentify t he p lants b eing u sed . F or t he s tandard m aterials, s imilarities w ere f ound a t s pecific w avelengths w ith e ach s ample o f t he s ame p lant d espite m any b eing o f d ifferent v arieties a nd f rom d ifferent g eographical r egions. D ifferences w ere s een a t s pecific w avelengths b etween e ach o f t he d ifferent p lants a nalysed s o f ar ( banana, s weet p otato, r ice, s ago, t aro a nd y am ). T here w ere d istinctive d ifferences b etween t he v arious p lants e ither i n t he s ize o f t he a rea u nder t he p eaks o r t he a ctual w avelength p eaks . A c omplete c hart o f t he h eptane I P w avelength o ccurrences f or e ach o f t he 4 5 p lant s amples i nvestigated i s g iven i n f igure 1 . A lthough i t v aries a l ittle f rom s pecies t o s pecies , r ather c lear d ifferentiation i s f ound b etween e ach o f t hese s ix p lants . T he d ifferences a re s ummarised i n t he P lant F ingerprint C hart i n f igure 2 . O ne o bvious a dvantage o f t his a pproach t o t he s tudy o f p lant r esidues i s t hat i t i s o biective, i .e t he i dentification a nd d ifferentiation i s b y c hemical c haracteristics . T he o nly s ublective e lement b eing t he i nterpretation o f t he d ata . H owever, t he b asic s pectra a re a vailable f or o thers t o e xamine, a nd r einterpret i f n ecessary , a nd a s t he a nalytical w ork i n g eneral i s l argely e auipmentb ased a nd o bjective i t c an b e e asily r epeated . T he a im o f t his w ork h as

4 50

E xtr. P lant

B a nana

Sweet Potato

F igure 1 .

F igure 2 .

1

Yam

a a a 1 I

I «

T aro

* 1 a a a 1 a

M i l

Sago

5 R V 0 0 0 0 3 -0 -0 0 -0 A i t i d I / / 1 d 0 1 n n t , 1 1 1 1 1 1 1 1 4 1 1 d d d d d d d , d d I x I a g g a a a a a a I I a 1 1 1 1 1 1 I u 1 x I a I f x x I f I I a R x N a a x R x 3 R 1 I I R I I I R I I I I R I B I I f R I L B R i f N E B I I 1 1 I 5 I 5 1 1 s s x i B s x I I s a * x T 3 a I T I i x a a T 1 1 T i f x x T a T I x T 1 T I E i 1 1 a Y I B Y a I N Y I I a v x 1 E l . 1 1 4

R ice

B 1HB 1 3 2HS B 3HB B 4HC B SHB B EHC B 7HC B 3HC K IND K 2HF 1 K 3HB K 4HR K SHR K SHR R 1HR R 2HR R 3HR R 4HF 1 R SHR R SHC R SHF 1 R PHf l C PHB C RHR 5 RH2 S 2HR 5 3HB 5 4HF 1 5 SHR S EHR T INS T 2HR T 3HR T 4HR T SHR T EHR T 7HR T E IHR Y 1H8 Y 2HB V 3HR V 4HR Y SHR V EHR V 7HR

0 0 B i n n d d 1 I x I I i i x 1 a a i B u a R R R R R R R R I R a E I B a a 1

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x

0 0 0 • ö 0 0 B O — 1 0" U 1 1 0 A l l O g g d p i d I F 1 1 1 1 t I t I A N N N e l d t d r i d d d d d d d d d r i i i E . I 1 i t g E a a I B g g E a i g a a e I a a B I E t I a a 5 1 K 1 1 1 1 I I I K B U 1 I K B I 3 1 K B 1 1 E K t 1 I N 1 K 1 E 1 I R R B B 1 1 1 Ri f I I a I 1 B B B R E 1 1 N I R B 1 1 O E II E R I 1 1 1 1 I R I I R I 1 I f I I I E I t R I 3 1 1 1 1 1 2 1 I I I N E 1 1 E 1 R I II I I 1 I 1 1 1 I I 1 I 1 x x x i l l N 1 1 1 I I f 1 I x a a 1 1 1 1 1 I I 1 I I I 1 I f 1 I I 1 1 1 1 I x a x 1 1 1 1 I I I 1 1 1 l i t i I I I I 1 1 1 1 I I I I I i 1 1 I I x x I a I I I I I I E 1 1 1 I I I E E g g I 3 I I 1 a x u x *

5 T V 0— d O d d d d a

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i

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R ice

( Strong )

1 720 1 710

S ago R ice

( Strong )

1 6 60 1 600

Y a r n T aro

1 510

S weet P otato

1 370

R ice

1 260

B anana

110

S ago

100

T aro

1 060

Y a r n

1 020

B anana

970

Y a r n

900

T aro

I R p lant f ingerprint c hart.

451

1

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° 8 0 1 r o n

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1 740

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b een t o e stablish t he b asic t echniques d escribed a nd t hen t o a pply t hem t o t he s tudy o f r epresentative w ell-dated p ottery s amples ( and t heir p ossible f ood r esidues ) f rom a w ide r ange o f i sland s ites a cross t he P acific . I n t his w ay , t he m ethod c an c ontribute o bjectively a nd i ndependently t o t he k nowledge b eing b uilt u p i n m any f ields a bout t he m ovement o f p lants a nd p eoples f rom A sia i nto a nd t hroughout t he P acific. I n o rder t o e stablish w hether u ltra v iolet s pectroscopy a m could b e u sed a s a m eans o f s econdary s upport f or a ny d ifferentiation f ound a t t he I R l evel, e xtracts f rom 2 9 o f t he o riginal 4 5 p lant s amples w ere a nalysed w ith UV . A lthough t he r esults f rom t his s eries o f t ests a re n ot y et c ompleted, a nd d espite t here b eing l ess c onsistency i n w avelength o ccurrences t han w as f ound w ith I R , t here s till a ppears t o b e s ome p otentially u seful g roupings , a s i llustrated i n f igure 3 . I t i s w orth n oting a s w ell t hat t he U V w avelengths w ere p lotted i n s teps o f 2 , a nd s o w hen d ealing w ith a p eak t hat i s w ider t han 2 w avelengths i t m ight h ave b een i dentified a s b eing o n e ither s ide o f t he t rue p eak l ocation . S everal w avelength r eadings c ame v ery c lose t ogether, s uch a s 2 55/259 , a nd i f t he p recise l ocation o f t he " shoulder" h as b een m isread t hen t he p ossible g roupings a s t hey a ppear s o f ar m ay a ctually b e c loser i n r eality . W ork i s c ontinuing o n t he r emaining p lant s amples s o t hat a d irect c omparison c an b e m ade b etween t he e ffectiveness o f UV a gainst t he r esults o f t he I R a nalysis i llustrated i n f igure 1 .

1 I « N 1 N Ba nana

Sweet Potato

R ice

Sago

T aro

Ya m

8 1 B 2 8 3 8 4 B S B E 8 7 B B

t ,

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P

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5 5

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F igure 3 . U V w avelength o ccurrences f or 2 9 p lant s amples

4 52

5

5

T he n ext s tage i n t he t his p rogramme w as t o a pply t hese t echni c : rues t o a rchaeological s amples t o i dentify t he f ood p lants u sed a nd t hus, t hrough a n a ccumulation o f d ated o ccurrences f or p articular p lants , t o g auge p ossible m igration r outes f rom A sia i nto t he P acific . A m ajor a dvantage o f t his a pproach i s t hat i t c ould i ndicate h uman p opulation m ovements , o r p lant u ses i n p rehistory , i ndependent o f o ther f orms o f r esearch o r o f c urrent h ypotheses. T he a rchaeological a rtefacts f rom w hich t he s amples f or s tudy w ere e xtracted h appened , i n t his c ase , t o b e c eramics a nd s oil s amples b ut t he a nalytical m ethod c ould b e u sed o n e xtracts f rom a w hole r ange o f d ifferent m aterials . T o t est t he a bility o f i nfra-red t o s creen a rchaeological s amples f or i nteresting o rganic r esidues , s herds a nd s oil s amples f rom s everal P acific s ites h ave b een a nalysed . A nalysis h as r ecently b een l argely c ompleted f or s amples f rom t wo i sland s ites i n t he s outheast S olomon I slands, n orth o f t he N ew H ebrides - N endo o n S anta C ruz I sland a nd N gaua o n t he R eef I slands ( Appendix 1 ) . T he r esults o f t he I R a nalysis o f t he s amples a ppears i n f igure 4 . UV s pectroscopy w as a lso c arried o ut o n t hese s amples, a nd t he w avelength o ccurrences a re s hown o n f igure 5 .

0 0 0 R J R Sherd h N t, R S1 R S2 R S3 R S4 ( 3 1 21 R R2 R E3 R R' S

t - 0 - 0- 0- 1 0 0 0 0 1 0 0 0 0 0 0 0 i d i N u s d e g d O I R N r i l l t R t f R R A I M N 1 \ 1 1 1 1 1 1 1 1 1 3 l i a l l t

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2 28

2 32

2 56

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1

I

3 32

S

S S

P

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S

S

AR1 A . R2

S

P

AR3

P

P

P

3 36

P

P

A S3

AR4

2 60

P

5 - Shoulder, P - Peak

F igure 5 . U V w avelengths f or t he S olomons s amples.

4 53

S

0

E 1

1

P

P

A S2

2 58

0

1 1 1 I

1 1

I

I

0 1

1

F igure 4 . I R w avelengths f or S olomons s amples

2 26

0

1

1

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A rchaeological b ackground T he S olomons i s ap articularly c rucial a rea f or s tudies o f t he m ovement o f p eoples a nd p lants t hrough Melanesia a nd i nto P olynesia . I n f act D .E .Yen, a w ell-known N ew Z ealand a rchaeobotanist , c oncluded t hat t he a gricultural s ystems o f t he S olomon I slands i ndicate t hat t he a rchipelago w as a c orridor f or t he t ransfer o f c ultigens a nd t echnologies t o t he C entral P acific." ( Yen, 1 976a p .74 ). T here i s n ow a s ubstantial b ody o f a rchaeological e vidence w hich c an b e c orrelated w ith t he l inguistic d ata t o a rgue t hat a ncestors o f t he P olynesians c ame f rom t he N ew H ebrides i n E astern M elanesia o ver 3 000 y ears a go a nd s ettled i n t he a rea o f F iji, T onga a nd Samoa, o ver 1 200 k ilometres a way . I n t his i solation t hey b ecame t he f ounding p opulations . I n c rossing t he a ndesite l ine t hey f ound l imited p lant , a nimal a nd g eological r esources , a nd t he c ulture a nd l anguage a dapted o ver a t housand y ears t o b ecome w hat w e w ould n ow c all P olynesian . T his movement f rom E astern Melanesia t o t he a rea o f F iji, T onga a nd S amoa a lmost c ertainly p assed t hrough t he S olomons ( Greem , 1 974 p .254). T o u nderstand t he t ype o f p eople w ho r eached P olynesia, a nd t he c ultural a nd p lant b aggage t hey m ay h ave c arried w ith t hem , a c loser l ook i s n eeded a t t heir r esources i n t he S olomon a rea . A n u nresolved d iscussion i s s till i n p rogress o n t he l ikely f ood r esources a nd h orticultural p ractices . P art o f t his i nvestigation w as a imed a t o btaining i nformation a bout t heir f ood r esources f rom r esidues o n p ottery , i n t he h ope o f e stablishing w hat m ay h ave b een t aken w ith t hem i n t he w ay o f p lants, o r w hat d eveloped s oon a fter s ettlement. T he a ncient c ultural c omplex f rom w hich t he i nitial P olynesian c ulture o f T onga a nd S amoa e volved i s c haracterised b y a d istinctive t ype o f p ottery c alled L apita , a fter a s ite f ound o ver 6 0 y ears a go o n t he w est c oast o f N ew C aledonia . L apita s ites d ated t o b etween 3 250 a nd 2 450 y ears a go a re w idespread t hroughout t he M elanesian i slands e ast o f N ew G uinea . T he c eramics f rom t he e arliest s ites i n e ach i sland g roup a re s o s imilar t hat a c ommon o rigin i s s uggested, a nd a r apid s ettlement o f t he s ites o ne a fter t he o ther o ver o nly a f ew c enturies s eems t o h ave o ccurred . T he s ites t end t o b e a ssociated w ith r aised b each l evels . R esults o f p etrographic a nalysis o f t he o bsidian a nd c hert o bjects f ound h ave s uggested t hat t hese m aterials w ere m oved o ver c onsiderable d istances . C learly t he s ame a bility t o e ngage i n e xtensive o cean t ravel w ould h ave b een r equired t o e ffect a ny r apid d istribution o f t hese L apita s ettlements o ver 4 000 k ilometres o f t his o cean . T he s tructural a nd s tratigraphic r ecord o f t he N gaua s ite o n t he R eef I slands ( SERF2 , Appendix 1 ) i ndicates t hat i t w as o ccupied f or s ome y ears , a nd g rew i n s ize d uring t hat o ccupation . D uring t his p eriod t he h eavy g athering o f t ridacna a nd t rochus s hells r esulted i n a r educed p opulation o f t hese s hellfish . N umerous b ones w ere a lso f ound o f t urtle , p ig b ones , t usks , t eeth a nd c hicken b ones . T he f ood v alue o f t he m arine f auna h owever w ould h ardly h ave b een s ufficient t o s upport a s mall p opulation f or a f ew w eeks , l et a lone a l arger p opulation o ver a n e xtended p eriod . T he p igs a nd c hickens, e arth o vens , p its , h ouses , a nd t he a dzes, s hell s crapers a nd o ther t ools a ll i ndirectly i mply s ettlements w ith a ccess t o t ropical r oots , t ree c rops a nd a gricultural p roducts e ven t hough t his c annot b e d emonstrated d irectly . T he c hange

4 54

i n t he L apita c eramics o f t he S anta C ruz-Reef I slands r egion o ver a p eriod o f 6 00 y ears ( 1000 y ears i f t he r adio-carbon d ates a re c orrected f or n ew h alf l ife v alues a nd s ecular e ffects ) i s l ess d ramatic t han i n T onga a nd F iji. U nlike s equences i n F iji a nd T onga, t he d ecoration s hows l ittle d ecline . I t i s b elieved t hat t his w as d ue t o s ome v essels b eing c ontinuously i mported f rom o ther L apita c ommunities i n t he w est over t he w hole o f t he p eriod . C hanges i n t he w estern L apita c eramic s eries w here t here w as c ontinued c ontact w ith o ther L apita c ommunities w ould s eem t o b e q uite d ifferent f rom t hat i n e astern L apita c eramic s eries w here g roups e volved i n i solation ( Green , 1 974 p .255 ). T here i s a c ase f or t he d evelopment o f t his L apita c ulture w ithin t he B ismark a rchipelago ( Flouae, T alasea a nd A mbitle ) b y 4 000 B .P ., a nd i ts s ubsequent d ispersal t hroughout I sland Melanesia . T he e arliest r eliable d ates f or L apita o utside t he P ismarks a re a ll l ater t han 3 500 B .P . N ew e vidence f rom P . 1 7 .Kirch i n 1 981 a llowed t he s outheast S olomons p ottery c omplexes t o b e p laced f irmly w ithin t he L apita t radition . " Far f rom L apita b eing a b asically i ntrusive S outheast Asian c ultural c omplex , i ts f orm a nd m uch o f i ts c ontext m ay h ave d eveloped i n t he n orthwest M elanesian a rea . O ver m uch o f I sland M elanesia, L apita c ould w ell b e t he f ounding c ultural c omplex, a s i t i s i n F iji a nd Western P olynesia . O ur p resent p icture o f L apita s ettlement p atterns a nd s ite d ensity m ay b e s everely s kewed b ecause o f p ost-depositional l andscape c hange o n t he l arger i slands . S ubsequent c ultural t raditions , a ceramic i n t he s outheast S olomons a nd l inked w ith Mangaasi-style c eramics i n m uch o f t he r est o f I sland M elanesia , c ould h ave d eveloped o ut o f L apita a nd t herefore n ot b e i ntrusive . T hus a n a rgument f or c ultural c ontinuity c an b e m ade i n I sland Melanesia a s i t i s f or w estern P olynesia . T his p rovides u s w ith a s impler f ramework o f S outhwest P acific p rehistory , b ut I w ould c laim , an o l ess i nteresting o ne ." ( Spriggs, 1 984 p .222 ) Y en n oted t hat t his a rea w as t he c entre o f d istribution o f L apita s ites a nd o f c onsiderable i mportance i n c onsidering h uman d ispersals i n P olynesian p rehistory . H e a lso d rew a ttention t o t he f act t hat t he e stablished d omesticates s uch a s t aro , y am , b readfruit e tc ., a re s hared t hroughout Melanesia a nd P olynesia, a nd a re r egarded a s t he a ccompaniments o f t he s pread o f h uman p opulations i n t he P acific ( Yen, 1 982 p .288). T his s ummary o f t he c ontroversy o ver m igration r outes , p lants a nd c ultivation m ethods s hould p rovide s ome i dea o f t he s cale o f t he p roblem . H owever, t here i s n ow a n i ncreasing r ange o f s cientific t echniques t hat m ay h elp a rchaeological u nderstanding o f Melanesian a nd P olynesian p rehistory . As S priggs c ommented " . .. w hile i t i s t rue t hat g rain c rops s uch a s r ice a re e asier t o detect i n t he a rchaeological r ecord t han a re t he r emains o f t uberous c rops, t he s earch f or t he l atter i s b y n o m eans a s h opeless a c ause a s h as b een a ssumed b y v arious a rchaeologists . Much m ore r esearch c ould b e u ndertaken i n i dentifying p lant r emains - p ollen, p hytoliths a nd m acroscopic e vidence." ( Spriggs, 1 982 p .7).

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R esults I n o rder t o e xtend t he p otential r ange o f a nalyses , I F ' , UV a nd G LC ( Gas L iquid C hromatography ) h ave a ll b een u sed t o b oth i dentify p ossible d ifferences b etween t he r eference p lants, a nd a lso t heir p ossible p resence i n r esidues o n s herds . T he r esults o f t hese a nalyses, a nd t heir s ignificance f ollow . F or i nformation a bout t he a rchaeological s amples e xamined, s ee A ppendix 1 . A S1 - T he i nfra-red s pectra f or t his s ample i ndicated t he p ossible p resence o f s weet p otato . T here i s s ome p ossibility t hat t he UV f requencies f or t his s ample, s hown i n f igure 5 , m ight a lso b e i ndicating t he p resence o f t he s weet p otato , b ut m ore c haracterisation work n eeds t o b e d one. T he G LC a nalysis f or t his s ample p roduced l inoleic, l inolenic a nd o leic a cids, b ut a l ikely p lant o rigin f or t hese i s n ot k nown . A S2 - N either I R n or UV p rovided a ny i ndications o f p ossible p lant r esidues o n t his s ample. A S3 - T he i nfra-red s pectra s howed a s trong i ndication o f t aro, a nd t he UV r esults m ight a lso i ndicate t his p lant . Aw eak i ndication o f l inoleic a nd o leic a cids w as p roduced b y G LC a nd t his m ight s uggest t he p resence o f s eed f at . A S4 - I P a nd U V a nalysis p rovided n o d ata , b ut G LC i ndicated p almitic a nd o leic a cids . T his w as d escribed a s a ' soil s ample ' b ut t he e xcavator n oted t hat " i t m ay b e m ore m aterial a nd p owder o ff s herds a nd s tone r ather t han a p roper s oil s ample" ( Green , 1 986 ). A R1 - I R a nd U V p rovided n o c lear d ata f or t his s ample , b ut G LC s howed p almitic , p almitoleic a nd o leic a cids w hich s uggests r esidues o f a f ish o r f ish p roduct o rigin . A R2 - A s I R a nd U V p rovided n o d ata , t he p resence o f p almitic a nd o leic a cids s hown b y G LC a nalysis m ay s uggest p ossible s oil c ontamination o r d egraded p roducts. A R3 - I nfra-red s uggested t he p ossible p resence o f s weet p otato, t aro a nd y am . At t his e arly s tage w ith UV c haracterisation, i t i s n ot c ertain b ut t here m ay b e p ossible c onfirmation o f t he I R r esults i n t he s pectra p roduced . A R4 - T his w as a nother s oil s ample, a nd I R, UV a nd G LC p roduced n o r esults . R esidues f ound i n p ottery t herefore a re u nlikely t o b e t he r esult o f s oil c ontamination. A ll e ight s amples s howed s hades o f y ellow i n t he e xtracts r anging f rom s light t o v ery b right , a nd t his c olouration h as y et t o b e e xplained . A s ummary o f t he b asic r esults i s g iven i n f igure 6 . T he c onclusion t hat t here w as a p ossible u se o f s ago , t aro o r y am a round 4 000 y ears a go w ould n ot p resent a ny p roblems , b ut t he i dea t hat s weet p otato w as b eing e xploited would . T he s weet p otato ( Ipomoea b atatas ) i s n ow w idely b elieved t o b e o f S outh A merican o rigin a nd i s n ot t houaht t o h ave e ntered p arts o f P olynesia f rom t he e ast u ntil

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r elatively r ecently a nd t o h ave b een i ntroduced i nto M elanesia i n t he w est b y t he P ortuguese 1 400 y ears a go .

A S1 A S2 A S3 1 S4

3 250 - 3 150 B .P . ( SZ8-Lot 9 7 ) -S weet P otato ( S1 -8-Lot 2 17 ) -N o d ata ( SZ8-Lot 2 01 ) -T aro & s eed f at? ( So i l S amp le ) -N o d ata 3 050

A R1 AR2 AR3 AR4

( RF-2-Lot 1 27 ) ( RF-2-Lot 3 15 ) ( RF-2-Lot 2 85 ) ( So i l S amp le )

B .P . -F ish o r f ish p roducts -N o d ata -S weet p otato , T aro , Y am -N o d ata •

F igure 6 .

R esults o f S olomons I R a nalyses

A s Y en s ays " All t he c rops o f S anta C ruz w ere g rown i n a s ystem o f s widden f ields o f y ams , D ioscorea s pp ., o n s lopes a nd t aro , C olocasia e sculenta ( L . ) S chott ., o n t he f lat l ow lying a reas, w ith p ermanent s tands o f t rees p roducing f ruits , n uts , f ibres e tc . a nd t he p erennial a roid ( Cyrtosperma c hamissonis ( Schott ) Merrill. The s weet p otato, I pomoea b atatas ( 1 ) L am ., w as u nknown ." ( Yen, 1 976b p .204). H owever Y en, a n a cknowledged e xpert o n t he s weet p otato a nd P acific plants g enerally, h as a cknowledged t hat even a t t he g eographical e xtremities o f i ts c overage , H awaii, E aster I sland , F iji, N ew G uinea, N ew Z ealand a nd P eru, t he s weet p otato h as p roduced s eedling v arieties . T here i s t herefore t he p ossibility , n o m atter h ow r emote, t hat t his p lant e ntered p arts o f t he P acific t hrough s eed t ravel, a nd t his c ould possibly e xplain u nexpected o r e arly o ccurrences. C learly m ore a nalysis i s n eeded t o p roduce c onfirmation o f p ossible s ources, a nd t o i ncrease t he r ange o f plant s tandards r equired t o a ssist i n t he n arrowing d own o f t hese s ources . W ork i s p roceeding w ith GLC on t he s amples o f t he s ix plants t o s ee i f t here i s a d ifferential p attern p roduced b y t he f atty a cids p resent i n e ach p lant . S o f ar t he r esults h ave n ot p roduced c onsistent p atterns. R EFERENCES G reen R .C . ( 1974) S ites w ith L apita p ottery : M ankind 1 9(4 ) 2 53-9 G reen R .C.

( 1986)

i mporting a nd v oyaging

P ersonal c ommunication.

H ill H .E. & E vans J . ( 1987 ) T he i dentification o f p lants u sed i n p rehistory f rom o rganic r esidues . I n W .R . Ambrose & J .M .J . Mummery ( eds ) A rchaeometry : F urther Australasian S tudies T he A ustralian Ntional U niversity , C anberra 9 0-6

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S priggs M . ( 1982 ) T aro c ropping s ystems i n t he S outheast A sianP acific R egion : a rchaeological e vidence A rchaeology i n O ceania XVII 7 -15 S priggs M . ( 1984 ) 1 9(4 ) 2 02-23

T he L apita c ultural

c omplex

J .Pacific H istory

Y en D .E . ( 1976a ) A gricultural s ystems a nd p rehistory i n t he S olomon I slands . I n R .C .Green & M .M.Cresswell ( eds ) S outheast S olomon I slands C ultural H istory R oyal S ociety o f N ew Z ealand , W ellington 6 17 4 Y en D .E . ( 1976b ) i bid 2 03-224

I nland s ettlement o n S anta C ruz I sland

( Nendo )

Y en D .E . ( 1982 ) T he h istory o f c ultivated p lants . I n R .J .May & H .Nelson ( eds ) M elanesia : B eyond D iversity R esearch S chool o f P acific S tudies , A ustralian N ational U niversity , C anberra 2 81-96

APPENDIX 1

S OLOMONS S AMPLES. D ate a nd s ite/location f rom w hich t hey w ere o btained

N endo, S anta C ruz I sland A S1 A S2 A S3 A S4

L ot 9 7 - S q .03 64 L ot 2 17 - S q .VV-50 L ot 2 01 - S q.HH 61 S oil ! - S q .PP 52 ( possibly m aterial a nd

N gaua, R eef I slands A R1 AR2 A R3 A R4

( SESZ 8 )

L ot 1 27 L ot 3 15 L ot 2 85 S oil !

-

2 nd l evel - 1 5-30 3 rd l evel - 3 0-45 4 th l evel - 4 5-60 4 th l evel - 4 5-60 p owder o ff s herds

( SERF2 )

S q.A-27 S q .U -35/6 S q.TS-40 S q .Y-56

-

s amples.

D ate 3 250-3150 B P . c ms - b rown s oil c ms - g rey/brown rey s and c ms - g c ms - g rey s and tones ) a nd s

s amples. D ate 3 050 B P.

m ostly g rey L ayer 2 - I st 1 0 c ms - g L ayer 2 rey - I st 1 0 c ms - g rey L ayer 2 I st l evel g rey s and

G rateful a cknowledgments t o P rofessor R .C .Green, C hair o f P rehistory, D ept. o f A nthropology, U niversity o f A uckland, N ew Z ealand.

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P HYTOLITBS: ANIMAL, VEGETABLE AND MINERAL?

A lix P owers D ept. o f A rchaeology a nd P rehistory , U niversity o f S heffield, S heffield S 10 2 TN

A bstract T his p aper d escribes t he p otential u ses o f p hytolith a nalysis f or p alaeo-ecological a nd p alaeo-economic r econstruction i n h ighly c alcareous e nvironments, s uch a s t he d une a nd m achair o f n orth w est S cotland , w here t he s urvival o f o ther o rganic m icrofossils i s e xtremely p oor. I t s tresses t he n eed f or t he e xamination o f a ll p ossible i nfluences o n t he c omposition o f t he f inal p hytolith s uites r ecovered f rom a rchaeological a nd n on-archaeological s ediments . I t i ndicates h ow d ifferences i n p hytolith a ssemblages h ave p rovided t he p otential f or l ocation o f b uried s ites i n d rifting d une s ystems . A lso , t hat p hytolith a nalysis m ay a ssist i n t he d ifferentiation o f s ources o f o rganic m aterials c ommonly r ecovered f rom a rchaeological d eposits , a nd t his m ay h elp t o e lucidate l and u tilisation a nd g razing p atterns . I ntroduction I n t he 1 950s a nd 1 960s, l ong b efore t he a dvent o f I ndiana J ones ( the m an r esponsible f or t he p ublic i mage o f t he a rchaeologist a s t he l eather-hatted, w hip-carrying r escuer o f d amsels i n d istress! ), t he a rchetypal a rchaeologist w as t hought t o b e t he e xpansive, m ilitary t ype, c omplete w ith m oustache . T his c aricature w as p rimarily a r esult o f t he p opularity o f a t elevision q uiz i n w hich ' expert ' g uests ( including o ne Mortimer Wheeler) w ere i nvited t o a ttempt i dentifications o f m ystery o bjects, o bjects a bout w hich t he i nitial q uestion p osed w as a lways " Animal, v egetable o r m ineral?" Much t he s ame q uestion i s a sked o f t he m aterial a nd a rtefacts r ecovered f rom a rchaeological s ites a nd , a t a s uperficial l evel, t his i s e ntirely t he c orrect a pproach . H owever, a rchaeology i s b y n ature a multi-disciplinary s ubject a nd i ts s tudy a h ighly e clectic a ffair. P hytolith a nalysis i s n o e xception . I n o rder t o s tudy p hytoliths o ne must c onsider t heir s ource a nd t he p rocesses b y w hich t hey a re d eposited i n t he s ediment ( leaving a side f or t he m oment t he q uestion o f p ost-depositional d iagenesis, a s ubject r eviewed b y R ovner ( 1986 )). T o b e s trictly a ccurate, t he t itle o f t his p aper i s s omewhat o f a m isnomer a nd s hould a ctually r ead " Phytoliths : m ineral, v egetable a nd a nimal" . B ut , a s t his r ather s poils ' the p lot ', I h ave c hosen t o b e d eliberately i mperspicacious a nd h ave f aith t hat m y r eaders w ill b e t he r everse . T he a im o f t his p aper i s t o p rovide a n i ntroduction t o p hytolith a nalysis a nd i ts p otential u ses i n a rchaeological s tudies f or p alaeo-ecological a nd p alaeo-economic r econstruction , i ncluding a c ase s tudy f rom n orth w est B ritain . A lso, i t s hows w hy i t i s i mportant i n p hytolith a nalysis t o s tudy a ll t he p ossible i nfluences o n t he f inal

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" suite" o f p hytoliths r ecovered f rom a rchaeological s amples . T hese i nclude t he b ehaviour o f t he m ineral i tself , t he p lants i n w hich p hytoliths f orm a nd t he a nimals ( including h umans ) w hich c onsume t he p lants . I n o ther w ords , t o p rove t he f olly o f t he r iddle t hat s tates t hat t he s ub jects h ave t o b e a nimal, v egetable o r m ineral . T he m ineral a nd t he v egetable . . . O pal p hytoliths a re l iterally " plant s tones" ( from t he G reek p hyton a nd l ithos ), a t itle f irst c oined i n 1 866 b y t he R ussian s oil a nalyst R uprecht . F ormed f rom s ilica - a m ineral m odern m an i s m ost c ommonly a cquainted w ith i n t he g uise o f g lass o r g emstone o pal - w hich o ccurs n aturally i n g round w ater, p hytoliths c an f orm i n a ll p arts o f ap lant b ut t heir d eposition i s n ot u niversal i n t erms o f t issues , s pecies a nd e ven a ges o f p lants a ffected . S ilicification i s , h owever, c ommon i n t he i nflorescence a nd l eaves ( Parry & S mithson , 1 957 ; 1 964 ; 1 966 ; S angster e t a l, 1 983 ). T he s ilica a dopts t he m orphology o f t he p lant c ell i n w hich i t i s d eposited a nd, t herefore, p hytoliths i n a variety o f s hapes ( 'morphotypes ') a re f ormed w hose a verage s ize i s a round 1 0 t o 7 0 m icrons , a pproximately t he s ame a s p ollen g rains ( Powers e t a l, 1 986 ). G roups o r " suites" o f p hytolith m icrofossils a re s tudies b ecause, u nlike p ollen, p hytoliths a re r arely s pecies s pecific . O nly v ery o ccasionally c an a d istinctive p hytolith m orphotype b e a ttributed t o a s ingle p lant s pecies, f or e xample t he c ross-shaped m aize p hytolith ( Pearsall, 1 978; P iperno, 1 984; P iperno & C lary , 1 984). T here i s, h owever, n o B ritish e quivalent t o t he m aize c ross . I nstead o f s earching f or i ndividually c haracteristic p hytoliths t he a pproach u sed h ere h as b een t o c onsider t he C omponents o f t he s uites a nd t o c ompare , b etween s amples , t he f requencies o f t he d ifferent m orphotypes . A b ody o f d ata i s p roduced b ased o n l ogged c ounts f or e ach o f t he m orphotypes w ithin e ach s ample . T he a im b eing t o i dentify ( if p ossible ) s ources o f o rganic i nput t o a n a rchaeological s ite i n t erms o f t he p hytolith s uites r ecovered . T he a pproach i s m ore c oncerned w ith t he g enerality o f e cological p lant g roupings a nd t he i dentification o f " artificial" c ollections o f p lant m aterial c aused b y h uman u tilisation t hat w ith t he s pecifics o f p lant i dentification. Most o f t he a rchaeological a nd b otanical s tudies s tudies o f p hytoliths h ave c oncentrated o n o ne f amily o f p lants , t he G ramineae o r g rasses , b ecause o f t heir i mportance a s d omesticated c ereals ( see P earsall 1 978 ; 1 982 ; 1 983 ; P iperno , 1 984 ; 1 985 , P iperno & C lary , 1 984 ; R osen , 1 987 ; R ovner, 1 983 ; 1 987 ). T hey a re , h owever, k nown t o o ccur i n aw ide r ange o f p lants i ncluding t he s hrubs , a nd t emperate a nd e xotic t rees ( Amos, 1 952 ; P iperno, 1 985 ), a lthough t he c omplete r ange o f p hytolith-producing s pecies i s n ot y et k nown . P hytoliths f orm i n p lants f or a v ariety o f r easons . M uch s ilica d eposition i s a r esult o f n atural g rowth a nd m aturation r equirements . A lso, s ilica m ay b e u sed o n t he s urface o f l eaves a nd s tems a s a s trengthening a gent f or d elicate s tructures s uch a s c ereal a wns o r h airs a nd s pines ( Hodson e t a l, 1 982 ; M etcalfe , 1 960 ; B lackman & P arry , 1 968 ). A p lant w ith w hich w e a re a ll f amiliar b ecause o f i ts p ropensity t o c ause a n i rritating r ash , i s t he s tinging n ettle - U rtica d iocia L . T he s pines w hich c ause t he a ggravation c onsist l argely o f f ragile

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s ilica w hich, w hen i t b reaks , p rovides t he n eedle s harp e dges w hich s o e asily p ierce h uman s kin ( Iler, 1 979; M artin & J uniper, 1 970 ). A dditionally , s ilicification o f s ub-surface c ells m ay o ccur i n r esponse t o p hysiological r eauirements, t o p rovide m echanical s upport f or e xample, o r a s ar esult o f e xternal s tress , s uch a s m icrobial o r i nsect a ttack ( Parry & S mithson, 1 958a ), o r w ater d eprivation ( Jones & H andreck , 1 967 ; P ovner, 1 983 ). T hus, t he p hytolith c ontent o f a ny d ependent u pon t wo f actors

a nd

i ndividual

p lant w ill

b e

1 ) t he i nherent g enetic a daptation o f t he p lant t o p articular e nvironments a nd c onditions ( "genetic" s ilicification ) 2 ) t he r esponse t o l ocalised " stress e vents", e .g w ater l oss o r i nsect a ttack ( "stress-induced" s ilicification ).

P lants w ithin i sland c ommunities w ill b e s ubject t o b oth g enetic a nd s tress-induced s ilicification t o v arying d egrees , d ependent o n l ocal c onditions . T herefore, s pecies c ommon t o m ore t han o ne t ype o f e cological z one m ay p roduce d ifferent p hytolith a ssemblages d ue t o t heir a ccommodation o f p ermanent/long t erm e nvironmental s tress o r s hort t erm s tress e vents . O f m ore s ignificance t han t his , h owever, a re t he v ariations i n d istribution o f p lant s pecies w hich h ave l ed t o t he f ormation o f d iscrete f loral u nits , w here d ifferent p lant c ommunities m ay p roduce d istinctive p hytolith s uites d ue t o v ariations i n t he p lant s pecies t hey c ontain a nd t he a daptation o f t hose s pecies t o e nvironmental c onditions. T he i dentification o f s eparate e cological z ones w ith d istinctive f loral u nits m ay p rove t o b e a v ery u seful t ool f or t he a rchaeologist . D istinct e cological z ones f orm a s ar esult o f t he a bility o f n ative p lant s pecies t o a ccommodate e nvironmental s tresses t hat a ct a s " limiting f actors" t o t he s pread o f o ther l ess w ell-adapted s pecies . P lants f ound o n c oastal s and d unes a re, f or e xample, a dapted t o c ope w ith v ery a ggressive e vapotranspirational c onditions c aused b y r educed g round w ater a vailability , t he p resence o f l arge a mounts o f o smotically a ctive s alts a nd h igher t han n ormal l evels o f r eflected i rradiation . I n o rder t o p revent e xcess w ater l oss i n t hese c onditions , t he p lants , i n a ddition t o p ossessing a typical m etabolisms , h ave v ery n arrow l eaves i n o rder t o p resent t he s mallest p ossible s urface a rea f or t ranspiration, a nd o ften h ave a t hick c uticle w hich a lso a cts t o p rotect t he p lant f rom s alt-burn w hich c auses d iscolouration o f l eaf e dges a nd s tunted g rowth ( Grime , 1 979 ). P lants u nable t o a dopt t hese s urvival s trategies w ill n ot w ithstand t hese h arsh l ocations a nd w ill b e " relegated" t o m ore c onducive e nvironments s uch a s i nland p asture . I t m ay b e p ossible t o u se p hytoliths f rom e cologically d istinct f loral u nits t o d etect v ariations i n g eographical u tilisation b y a ncient m an i n a reas s uch a s i slands w hich h ave m ajor e cological v ariations o ver r elatively s mall g eographical d istances . T he v egetable a nd t he a nimal . . . U pon p lant d eath, t he p hytoliths a re d eposited e ither d irectly o r i ndirectly i nto s ediments . r lants w hich m eet t heir d emise b y w ay o f t he t eeth o f l arge g razing u ngulates o r t he ' dinner p late ' o f a ncient m an ( rather t han a p ainless f ading a way ) f inally e nter t he s ediments b y w ay

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o f f aecal o r v isceral r emains ( Baker e t a l, 1 961; L ewis, 1 979 ). T he c omposition o f t he p hytolith s uites r ecovered f rom f aecal r emains w ill b e d ependent u pon t he t ype o f p lants c onsumed, w hich w ill v ary a ccording t o s easonal a vailability a nd g razing/collecting p reference , a nd u pon t he p arts o f t he p lant e aten, w hich i s a lso d ependent o n s pecies g razing/eating h abits . W hatever p lants a re " selected" ( be t he c hoice b e t hrough a c onscious h uman m anagement a nd/or c ollection o f p lants o r a n i nstinctive u ngulate g razing h abit ) t he " selection " w ill a ffect t he c omposition o f t he p hytolith s uites r ecovered f rom s ediments ( ignoring f or t he m oment t he q uestion o f d ifferential p reservation ). T herefore, p hytoliths r ecovered f rom a rchaeological s amples m ust b e c onsidered i n t he l ight o f p ossible v ariations i n t he p hytolith c ontent o f t he p lants a s a r esult o f e nvironmental s tress , s pecies s election; t he t reatment o f t he b otanical r esources a nd b urial h istory . O nce d eposited w ithin s ediments , p hytoliths a re h ighly r esistant t o d ecay a nd d ecomposition b y b iological a nd c hemical a gents, a nd h ave b een r ecovered f rom a w ide r ange o f s ediment t ypes, f rom a cid p eats t hrough t o c alcareous s ands w ith t he p H o f u p t o 9 .8 ( Lewis, 1 979; P ease, 1 967 ; P owers & G ilbertson, 1 987a ; R ovner, 1 983 ). T he h ighly r esistant n ature o f t hese p lant f ossils m akes t hem a n i deal c andidate f or p alaeo-ecological a nd p alaeo-geographical r econstruction , a nd f or t he i nvestigation o f a rchaeological s ites . S everal o f t he p articular a dvantages t hat p hytolith s tudies m ight h ave o ver m ore t raditional m icro- o r m acro-palaeontological a pproaches f ollow f rom t he f act t hat t hey a re c omposed o f s ilica, a s ubstance w hich i s r elatively s table b oth c hemically a nd p hysically ( Rovner , 1 983 ). I n c onsequence , i t m ay b e h ypothesised i nitially t hat p hytoliths, a s c ompared w ith o ther g roups s uch a s p ollen a nd s pores , w ill b e p referentially p reserved a nd h ence m ore a bundant i n c alcareous e nvironments s uch a s d une a nd m achair s ediments a s a r esult o f t heir c omparative r esistance t o m icrobial a ttack a nd d ecomposition , o xidation , l eaching a nd a ttrition ( Rovner, 1 983 ). l ' he q uestions I t w as p recisely b ecause p hytoliths w ere p otentially r ecoverable a nd i nterpretable f rom h ighly o xidising e nvironments t hat p rompted t he i nitial r esearch s ummarised h ere . F inanced b y t he S cottish D evelopment D epartment 's H istoric B uildings a nd Monuments D irectorate, t he s tudy e ntailed a nalysis o f a rchaeological s ediments f rom p rehistoric s ites w hich w ere u nder t hreat f rom t he c oastal e lemental e rosion o n t he m achair ( calcareous d une p asture ) a t B aleshare o n N orth U ist a nd H ornish P oint o n S outh U ist i n t he O uter H ebrides ( Powers & G ilbertson , 1 987a ) ( figure 1 ). T hese s ites w ere e xcavated b y t he H BM 's C entral E xcavation U nit , d irected b y J ohn B arber . I nvestigations o f s amples f rom m achair a t t he L inks o f N otland o n W estray i n t he O rkneys, A insdale N ational N ature R eserve o n M erseyside , a nd f ive s ites o n t he I sles o f U ist ( figure 1 ) p rovided c om p arative m aterial f rom w indblown s ands , v egetated s urface a nd s ubsurface d eposits . T he e xcavator o f t he U ist s ites , M r . J ohn B arber, o riginally p osed an umber o f q uestions t o w hich i t w as h oped p hytolith a nalysis w ould p rovide s ome u seful a nswers ( Powers &Gilbertson, 1 986; 1 987a ). T he q uestion o f m ost s ignificance h ere w as t he o ne c oncerning t he

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i dentification o f t he e xact o rigins o f t he r ich o rganic l ayers f ound w ithin t he a rchaeological m iddens . D ue t o t he v ery c omplex n ature o f t he s ites u nder e xcavation, a ll t he a rchaeological s amples w ere a ssigned t o " blocks" w ith t itles s uch a s ' windblown s and ', ' cultivated d eposit ' a nd ' midden ' d esignated b y t he e xcavator ( Barber, 1 988). I t w as t he r ich m idden d eposits t hat w ere o f t he m ost i nterest , a lthough a n umber o f o ther t ypes o f s ample w ere a nalysed. P hytolith s tudies o f s ediments d erived f rom s and d une e nvironments h ad n ot p reviously b een p erformed . T he s amples w ere t herefore p rocessed

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