Tools in Your Life

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PUBLIC LIBRARY COUNTY, IND. FORT WAYNE AND ALLEN ALLEN COUNTY EXTENSION DEPT.

ANTHONY 8338

.

Tools

in

Your

Life

J

Books by Irving Adler

TOOLS IN YOUR LIFE FIRE IN YOUR LIFE

TIME

IN

YOUR LIFE

THE SECRET OF LIGHT DISCOVER THE STARS (co-author)

IRVING ADLER

Tools

in

Your

Illustrated by

Life

Ruth Adler

The John Day Company

New

York

Copyright

©

1956 by Irving and Ruth Adler

must not be reproduced in any form without permission. Published by The John Day Company, 62 West 45th Street, New York 36, N. Y., and on the same day in Canada by Longmans, Green ir Company, Toronto. All riphts reserved. This book, or parts thereof,

Library of Congress Catalog Card Number: 56-5974

MANUFACTURED

IN

THE UNITED STATES OF AMERICA

^ 3cHoa

1*

C367560 Contents

I.

II.

Man,

f/i^

Tool-Maker

From Hunting

to

Farming

9

30

III.

Bronze and Iron

55

IV.

Power and Machines

79

V.

T00/5 an(i T/i^ir Uses

99

VI.

VII.

Invisible Tools T/ie TooZ^ 0/

Index

Today and Tomorrow

110 119 127

Tools

in

Your

Life

CHAPTER

Man^

the

I

Tool-Maker Eye

False Teeth and a Glass

BEAVERS

cut

down

trees

by biting

at the

wood

with their long, sharp front teeth. Man's front teeth are not as long and sharp as a beaver's, and are no good for biting

wood

at

all.

In spite of that,

man

than beavers can, and he does well at cutting

The saw is

wood by

faster, too.

man's power to bite and

bigger trees

Man

does so

made of hard steel. that he uses to make up for the

in his jaws.

replace his natural teeth.

A hawk

it

down

using a saw

a set of false teeth

weakness of the teeth

can cut

These

false teeth don't

They extend them, and add

to

cut.

has very sharp eyes that can spot his prey at a

great distance. Man's eyes are not as sharp as a hawk's. In spite of that,

farther

man

can see farther than a hawk can.

by using a telescope

metal tube. The telescope

is

made

a ^ass eye.

place of the eyes in man's head. to their

sees

It

doesn't take the

extends them, and adds

power.

The saw and

man

It

He

of glass lenses set in a

the telescope are examples of the tools

uses to help

him

in his

body

that

add

sions of his

work. They are

artificial

exten-

to his strength.

9

A Dwarf Becomes

a Giant

man had to rely on his body alone, he would be a dwarf among the animals, puny, naked, and defenseless. He is weak compared to an elephant that can push down a tree with its head. He is slow compared to a leopard that can run at a speed of seventy miles an hour. He can't hunt or If

fight as well as a

wolf that has sharp-pointed canine teeth.

He can't endure the cold as well as a bear that has a warm coat of fur. But man does not rely on his body alone. He uses and implements that serve can't push down a tree with a bulldozer.

He

thick

tools

as extensions of his body.

He

but he can do it with can't run seventy miles an hour, but he can his head,

on a railroad train. He can't kill a large animal with his teeth, but he can with a rifle. He can't protect himself from severe cold with his skin, but he can with clothing, houses, and stoves. Because he uses tools, man is travel

much

10

faster

not puny, naked, and defenseless. His tools giant

among animals— faster,

stronger,

make him

a

and better protected

than any other animal.

Doing the Impossible merely help man do better what he could do with his body alone. He can scoop up some soft earth with his hand, but he can scoop up more with a steam shovel. He can lift a weight with his hand, but he can lift a heavier weight with a crane. He can strike a blow with his fist, but he can strike a harder blow with a hammer. But there are other tools that help man do things that he cannot do at all with his body alone. Unaided, man cannot fly, because he has no wings. Unaided, man cannot live in the sea, because he has no gills with which to breathe under water. But the airplane has given man "wings" with which to fly. The diving suit has given him "gills" with which to breathe under water. Man's tools do not merely extend the parts of the body that he has. They also give him parts, like wings and gills, that he doesn't have at all. In this way they

Some

make

it

tools

possible for

him

to

do more

things.

They turn the

impossible into the possible.

Other Tool-Users

Man

is

not the only animal that uses tools. Tools are

sometimes used by other animals as different as a baboon, a wasp, a bird, and an otter. The baboon is a monkey that lives on the ground. When it finds a scorpion that it wants to eat, it will sometimes kill it with a pebble. The pebble serves as the baboon's hammer.

11

The Wasp's Hammer Ammophila, the burrowing wasp,

When first

a female

Ammophila

is

digs a hole in the ground.

also uses a

hammer.

ready to lay her eggs, she

Then she

and

looks for a cater-

She puts the caterpillar into the hole and lays an egg on it. She does this several times until the hole is filled with caterpillars, each one carrying an egg. Then she covers the hole with earth. Sometimes she picks up a pebble in her mouth, and uses it to pound the earth over the hole until it is just as hard and smooth as the surrounding ground. In this way she makes a safely hidden nest for the larvae that hatch from her eggs. When the larvae break out of the eggs they begin pillar, stings

it

to paralyze

it,

carries

it

to the hole.

eating the paralyzed caterpillars in the hole.

The

A

Finch's

Crowbar

bird that uses a tool

is

Cactospiza, a finch that lives in

the Galapagos Islands off the coast of Ecuador. Cactospiza

12

eats insects that it

it

digs out of the bark of trees. Sometimes

uses a small twig or a cactus spine as a crowbar to pry an

insect out of a crack in the bark.

The

Otter's Anvil

Southern sea otters

live off the coast of California.

They

dive to the floor of the sea to gather the shellfish that they like to eat.

An

otter that has a shellfish brings

it

to the sur-

and rests it on his chest while he floats on his back. Then he digs the meat out of the shell with his teeth. Sometimes he finds a small shellfish that he likes especially, but which has a very hard shell. When he brings this shellfish to the surface, he also brings up a stone from the sea floor. While he floats on his back he puts the stone on his chest. Then, holding the shell in both of his forepaws, he takes a face

13

J wide swing from behind his head, and smashes the shell on his stone anvil. Once the shell has been smashed he has no trouble getting at the meat inside.

Man Makes

His Tools

While the baboon, the wasp, the finch, and the sea otter also use tools, man is far ahead of them as a tool user.

They use larly.

tools only

But there

is

sometimes, but

man

uses tools regu-

another difference between them that

is

even more important. The tools used by the baboon, the wasp, the finch, and the sea otter are a pebble, a twig or a cactus spine, and a stone. These are things that you can find in nature. A pebble can be found on the ground. A twig or spine can be broken from a tree or bush.

A

stone

can be found under the water. All you have to do is pick them up, and they are ready to use. But man uses tools that

14

you cannot find in nature. You do not simply find electric saws on the ground or under water. Steam shovels do not grow on trees. These things are not found. They have to be made. Man has these useful tools because he makes them himself. Because man is the only animal that makes tools, Benjamin Franklin, America's first great scientist, described

man

as a "tool-making animal."

Different

Ways

of Living

There are thousands of different kinds of animals scattered far and wide all over the earth. Some live near the equator where it is hot. Some live near the poles where it is cold. Some live out in the open where there is light. Some live in caves or under the ground, where it is dark. Some live on the plains and some live in the trees. Some live in the air,

while others live in the sea.

under different conditions do things in different ways. For example, they have different ways of moving. Birds live in the air, and move from place to place by flying. Fish live in the water and move about by swimming. Horses live on the ground and move by walking or running. They couldn't exchange ways of moving, because you can't fly in the water or swim on the ground. An animal's way of moving fits the place and conditions under which it lives. Animals also have different habits of eating. Most birds that live inland feed on insects. Many birds that live near the water feed on fish. Some animals, like rabbits, eat only plants. Other animals, like foxes, eat meat. Some animals have a mixed diet, eating both plants and meat. Their feeding habits, like their ways of moving, fit the conditions under which they live. Animals that

live

15

Bodies That Fit

The

things that animals do

fit

the conditions under

which they hve, and their bodies fit the things that they do. A bird, a horse, and a fish all have four limbs. A fish's four limbs are fins that are fit for swimming. A horse's limbs are legs, with hooves that fit them for running on the plains. A bird has two legs it uses for walking or hopping, but the other two limbs are wings that are fit for flying.

A are

and a fox both have teeth. The rabbit's teeth biting and chewing plants like carrots, cabbage,

rabbit for

fit

and grass. The fox's teeth include long pointed canines that he can use for tearing the flesh of his prey. Man's Ways

Man

has his

on only two

own

special

ways

of doing things.

legs, instead of four the

way

He

walks

dog or a horse hands for making a

does. He stands up straight and uses his and using tools. He eats both plants and meat. He doesn't live by himself, but lives and works in groups. These have been man's ways of doing things for perhaps a million years.

He

ditions

does things

this

way because

under which he and

of the special con-

his ancestors lived.

Ancestors in the Trees

Man

is

a cousin of the gorilla and the chimpanzee. His

ancestors were apelike animals that lived in the trees. Be-

cause they lived in the trees they didn't walk on

They stood on

all

four

and used their forelegs for grasping branches and swinging from tree to tree. This is how man came to be an animal that walks on only two legs and stands up straight. legs.

their hind legs,

16 .)

Forced Out of the Trees

About a

million years ago there

the climate of the earth.

The big

was a great change

in

sheets of ice that surround

grow and spread out. the continents became so cold that trees

the north and south poles began to

Large parts of

grow there any more. This forced man's ancestors out of the trees. They now had to live on the ground, where food was scarce and danger was great. On the ground they continued to stand on their hind legs, the way they did in the trees. But their forelegs were no longer kept busy couldn't

grasping branches to swing from tree to legs

were now free and could be used

New

Foods and

New

tree.

Their fore-

in other ways.

Habits

Because food was scarce during the Ice Age, man's anhad to change their food habits. They used to eat fruits and seeds and insects. Now they had to begin eating meat. But their teeth were not the teeth of meat-eaters. They did not have long pointed canine teeth with which they could kill their prey and tear its meat. Since they couldn't count on their teeth, they made use of their forelegs, which were now free. Instead of grasping a branch, cestors

the foreleg could

now

grasp a stick to use as a club, or a

broken stone to use as an axe. The club or the axe made up for the weakness of their teeth. In this way their forelegs became hands that could make and use tools and do work. Man's tool-making was the result of the new conditions of life brought on by the Ice Age. It marked the beginning of

Age of Man. One man alone was the woolly mammoth,

the

weak

hunt large animals like or to protect himself from the new dangers that surrounded him. So men banded together for too

to

17

this way man's habit of Hving groups or societies also grew out of the conditions brought on by the Ice Age.

hunting and protection. In in

The

Age came

an end and was followed by a more Ice Ages came and went. The fourth Ice Age ended only about 10,000 first

period of

Ice

warm

years ago.

to

climate. But then three

When

the last ice sheets retreated to the north

and south poles, tool-making, hunting, and living in groups were already regular features of man's way of life.

The Body

of a Tool-Maker

The bodies

of animals

has a body that

is fit

fit

swimming. Man has a body that activity, making and using tools.

for

Man

A

bird

that

is fit

the things that they do.

for flying; a fish has a is fit

body

for his

own

special

because he has hands free for work instead of forelegs that he must walk on. His hands can do things that require much strength and little skill, like digging a ditch. They can also do things that require is fit

for tool-making

strength but much skill, liking fixing a watch. While he works, man's hands are guided by his eyes. Each of his two eyes sees a separate picture, and together they allow him to see depth, so he can judge distances, and control the movements of his hands. Man also has a flexible tongue and mouth with which he can speak. Because men can speak, they can understand each other and work together. But behind the hands, the eyes, and the tongue is another part of his body that is the most important of all, the brain. Man has the most highly developed brain of all animals. little

His brain controls the movements of his hands. His brain

keeps his eyes and his hands working together. His brain controls his speech. Because of his brain he can learn

18

how

to use old tools.

his brain

he can think up new

His brain makes plans, and then guides the rest of

tools.

the

Because of

body

in carrying

The Puzzle

them

out.

of Living Things

People have often wondered about the variety of animals and their fitness for the conditions under which they live and for the things that they do. "Why are there so

many

different kinds of animals?" they thought.

and earthworms, fishes and and men?" They also noticed how the

"Why

are

mosqui-

there elephants

birds,

toes,

larger animals

have special organs, parts of their bodies that divide up the work the body must do. They have legs for running, eyes for seeing, and ears for hearing. Each organ is specially fitted for the

work

it

does.

special organs?" they

questions, scientists

"How

did the animals get these

wondered. To try

made

to

answer these

a careful study of

all

living

They studied the animals of today by visiting the where they live in many parts of the world. They studied the animals of the past by examining fossils, the preserved remains of past life that are found buried in the ground. They studied animals that are struggling to live under natural conditions, and others, like cattle, dogs, and pigeons, that are protected and fed and bred by man. Through all these studies they gathered many facts. Finally, about one hundred years ago, the great English scientist Charles Darwin put the facts together and was able to answer the questions with his theory of evolution. things.

places

How

Living Things Change

According to the theory of evolution, the animals of today are descended from diflFerent kinds of animals that 19

began on the earth over a bilHon years ago. The earliest animals were probably small shapeless things like the amoeba, a tiny animal that looks like a drop of water. But, as the centuries went by, they evolved, lived in the past. Life

or changed, into the

many complicated

living forms of to-

became more and more fit for the special conditions under which they live, and their organs became more and more fit for the special jobs they day. As they changed they

do.

To

explain this evolution,

Darwin made use

portant facts about living things. First, there

when

is

of three im-

the fact that

animals have children, the children are like their

Dogs give birth to puppies, and the puppies grow up to be dogs. Cats give birth to kittens, and the kittens grow up to be cats. So, while each animal must die, each

parents.

kind of animal can live on, because the children take the place of their parents.

The second

fact

is

that,

although animals have children

like themselves, the children aren't all exactly alike.

may be

fast

Some

and others slow. Some may be strong and

others weak.

The

third fact

is

that in nature

all

animals have to

They are surrounded by dangers on all sides. Disease, bad weather, and other animals may bring sudden death. They have to hunt for their food. They often have to fight or run away to avoid being eaten by others. Frogs live by eating insects. Snakes live by eating frogs. So some animals must die that others may live. Because of all these difficulties and dangers, only some struggle hard to remain alive.

of the animals that are born live long

enough

to

have

chil-

dren of their own. Putting the three facts together gave Darwin a picture

20

of

how

evolution takes place. Because the animals of each

have the same chance of living a long life. Where they have to fight, the strongest fighters will live, and the weakest will die. Where they have to run away from danger, the fastest runners will live, and the slowest will die. The struggle to live picks out for survival those who have some advantage over the kind are not exactly

others, those

who

living. It picks

alike,

are

they don't

more

fit

all

to face the difficulties of

who have some who are less fit. As a result, it is those who live long enough to have children.

out for destruction those

disadvantage, those

who

more

are

fit

And, because children are usually like their parents, those who live pass on their advantages, their greater fitness, to their children.

Then

the

same process of

selection takes

place again as their children begin the struggle to this

way each new

generation becomes slightly more

the conditions under which eration

is

live.

it

lives.

The change

in

fit

In for

one gen-

very small, but after millions of generations the

change can be very great. live under the same conditions for a long time, they gradually develop and perfect the organs that are suited to those conditions. Because different animals live under different conditions, they have developed different kinds of bodies. That's why fish have fins, and birds have wings, while horses have legs instead. total

Where animals

The

Fit

Become

Hundreds

Unfit

of millions of years ago there

were great rep-

roamed the earth. The climate was warm, and many plants grew on the low swampy land. Plant-eating dinosaurs ate the plants, and meat-eating dinosaurs ate the plant-eaters. The dinosaurs flourished because tiles

called dinosaurs that

21

they had developed bodies that were just right for Hfe in the hot wet cHmate of that time. But then the chmate

changed. The land rose higher, and the

and

drier. In the

swamps died

out.

new

air

became

climate, the old plant

life

cooler of the

Because their food became scarce, the

plant-eating dinosaurs died out. This deprived the meat-

eating dinosaurs of their food, so they died out too. Be-

cause the dinosaurs were so

fit

for life in the old climate,

they turned out to be unfit for the

climate.

Many Changes

Fit for

The example good

new

of the dinosaurs

shows that

it

is

not too

be fit for only one set of conditions. Conditions on the earth have been changing all the time. Continents have risen out of the sea. Mountains have been formed and then to

have been worn down many times. Glaciers have grown and then melted again. Besides these changes, which are slow and take thousands of years, there are other changes that are faster and happen more often. The seasons change from month to month, and the weather changes from day to day. We have hot days and cold days, rainy days and dry days. At the same time day follows night, and night follows day. Because of fitness

is

fitness for

all

these changes, a better kind of

changing conditions. To have

this

kind

must have a way of noticing the changes, and of changing its behavior to match every new condition. It must know when to hunt and when to hide, when to fight and when to run away. An animal also has the best chance to survive if it can learn, so that it will stop of fitness an animal

doing dangerous things, while

and

better.

22

The

it

does useful things better

part of the animal's

body

that

makes

this

possible

is

the nervous system, and especially the brain.

That's why,

changed with brains, until

Man

world changed, and living things animals appeared with better and better

the

as it,

man came

along with the best brain of

all.

most fit for life under changing conditions because makes it possible for him to think, to speak, and make and work with tools. is

his brain

to

A New Man

Kind of Evolution first

emerged

as the tool-making animal

about a

marked the close of one chapter in the story of evolution, and the beginning of a new one. Tool-making has changed the way in which evo-

million years ago. His appearance

lution takes place.

Other animals,

must depend almost

They

entirely

in their struggle for life,

on the organs of

their bodies.

and run and the best organs generation. So, little by little,

see with their eyes, bite with their teeth,

with their

legs.

Animals

live

survive from generation to

evolution has produced

and

many

die,

kinds of animals with

many

kinds of organs fitted for special jobs like seeing, biting,

and running. But man does not rely on his organs alone. He makes and uses tools which are extensions of these organs.

He

sees with the help of eyeglasses, microscopes,

and radar. He "bites" with the help of axes, saws, knives, and chisels. He "runs" with the help of wagons, automobiles, and locomotives. Men live and die, and the best tools are passed on from generation to generation. So, little by little, there has been an evolution of tools, producing many kinds of tools, each more and more fit for the special job it does. The history of man is built around

telescopes,

the history of his tools.

23

Evolution of the Hand-Axe

The way

tools have changed is shown by what happened one of man's first tools, the hand-axe. The first hand-axes were probably just broken stones that men found and used as they were. Later the hand-axes were made. Men discovered they could shape the axe by chipping pieces from a stone. The stone that they found to be most useful was flint, although others were also used. The hand-axe was a many-purpose tool. Its sharp end was used as an axe for chopping wood. It could also be used as a knife for cutting meat, and as a scraper for removing hair and flesh from skins. But each of these jobs could be done better by tools specially shaped for them. So gradually tools of many shapes and uses began to be made. Among the later tools we find short and heavy ones for

to

24

chopping; long, straight, and thin ones for cutting; and

curved ones, used hke spoke-shavers, for shaping wood. Then men made an important discovery. They found they could strike a harder blow with an axe tied to a handle

than with an axe merely grasped in the palm of the hand.

The handle was a simple machine that turned a small force exerted by the hand into a great force delivered by the axe. It made men stronger than they are by nature. Handles were attached to other cutting tools too. They were attached to adzes that were useful for hollowing out logs of

wood,

to

covered

even

make bowls and even

how

to plant seeds to

canoes. After

grow

their

own

men

dis-

crops, they

teeth in wooden handles to make down the grain. time when farming first began, about men also discovered a new way of shap-

set little stone

sickles for cutting

At about the 7,000 years ago, ing their tools.

They began

to grind the edges of their

25

became when they metal, that made

stone tools, instead of chipping them. Grinding

more important about

a thousand years later

found a way of getting a new material, began

better tools than stone. First bronze of stone.

Then

to take the place

iron took the place of bronze. Metal tools

can be given even more shapes than stone tools, so more and more special cutting tools were developed. Improved chisels, gouges, and saws made complicated woodwork possible.

Today

special mixtures of metals, called alloys,

can be given a hard cutting edge, so

we have

tools for

cutting metals as well as tools for cutting wood.

Putting handles on their tools gave men a way of doing hard work with less effort. But they still had to use their muscles to supply the force behind the tools. Later they found a way of doing even harder work without using their muscles at all. They harnessed forces of nature and put them to work to supply the power to operate the tools. So now, in addition to hand saws, we have electric saws run

by

electric motors. In addition to

hand

sickles,

we have

reapers pulled across the fields by Diesel-engine tractors.

We

have gone a long way from the many-purpose handaxe chipped out of a piece of flint.

From Digging

Stick to

Steam Shovel

was the digging stick. It too first it was merely a pointed stick, found and used the way it was. Later it was a stick that was cut and purposely given a point with the help of a hand-axe. Then slight changes gave it many shapes for many special purposes. Making the stick curved turned it into a plow. Making the end flat instead of Another of man's

has undergone

pointed turned

26

first

many

it

tools

changes. At

into a shovel. Attaching several pointed

one handle turned

sticks to later

replaced

wood

at the

it

Metal

into a spading fork.

wood

digging end, while

con-

Then power was harnessed to was used to operate cutting tools

tinued to serve for handles.

digging tools the

way

it

and hammers. The steam shovel of today

is

the descendant

of the simple digging stick of the past.

Evolution Picks

Up

Speed

Tools are extensions of the body, but they are not part of the body.

They

longer by picking

are detachable.

up

a

A man

can make his arm

hammer. He can shorten

it

again by

hammer down. Because it is detachable, he can hammer away and replace it with a better one. So,

putting the

throw a

while his arm does not change, the

size,

use of his

hammer may change many

has

arm he was born

is

the

with.

the shape, and the

times.

The

The arm

tools that

a

mHn

he has are

tools he has learned about, or that he invented himself, and that he and other people have made. For these reasons, tools change much faster than organs of the body. The men and women of today have the same kinds of bodies as the men and women of one hundred years ago, or even one thousand years ago. But they have more and better tools

than their ancestors did. Tools

make

it

easier for

man

do

to

his work.

But part of

work is inventing new tools. So tools make it easier to make new tools. The more tools we have, and the better they are, the faster we can make more and better tools. For his

this reason, the evolution of tools

from century to century. million years, fishing,

when men

and gathering

speed after

men

It

goes on faster and faster

advanced slowly

for

about a

by hunting, and herbs. It picked up plant crops and breed ani-

got their food only

roots, fruits,

learned

how

to

27

mals, about 7,000 years ago.

It

moved ahead

faster

with

the growth of handicrafts in the great cities of ancient

Babylonia, Egypt, India, China, Greece, and Rome.

It

broke

Europe a thousand years ago. Now it is galloping on as commerce and industry spread factories all over the world and turn the world itself into one great into a trot in

complicated workshop.

More and More

Fit for Less

and Less

There are tiny animals today that resemble the first animals that lived about a billion years ago. The amoeba is one of them. It lives in fresh-water ponds, and is too small to be seen without a microscope. The body of an amoeba looks like an irregular drop of water. It moves by pushing part of its body forward as a false foot, and then flowing into the foot. Any part of it can become a "foot." It eats by flowing around its food and surrounding it. So any part of it can become a "mouth" or a "stomach." It breathes by drawing in oxygen from the surrounding water, so any part of it serves as "gills." It is sensitive to light and to sound. So any part of the body can be an "eye" or an "ear." The body of an amoeba is a jack-of-all-trades and master of none. The animals that developed in later stages of evolution are quite different. As the millions of years rolled by, the animals developed specialized organs, each one doing a specialized job, and especially fit for the job it does. An eye is sensitive to light, and serves only for seeing. An ear is sensitive to sound, and serves only for hearing. Because the organs are specialized, each one does its own job better. But because an organ is more fit for its special job, it is unfit for other jobs. An eye can see, but cannot hear. An ear can hear, but cannot see. So the development 28

of specialized organs has

made each

part of the

body more

and more fit to do less and less. As their organs became specialized, animals became specialized too. A penguin has wings that are specialized for swimming. So a penguin can swim but cannot fly. A sparrow has wings that are specialized for flying. So a sparrow can fly but cannot swim. Evolution produced kinds of animals that were more and more fit for less and less.

More and More The

Fit for

the

first tools, like

all-trades.

More and More

The hand-axe,

first

ting or scraping.

A

pound

We now

have special

tools

for chopping, different ones for cut-

specialized tool does

as well as cut,

its

own

job better,

While a hand-axe was able a sledge hammer can pound but

but cannot do other jobs at to

jacks-of-

was used for hamand scraping. As tools evolved,

they too became specialized.

hammering, others

were

for example,

mering, chopping, cutting, for

living things,

all.

cannot cut, and a scalpel can cut but cannot pound. In this respect the evolution of tools It

and more fit But man's

and

do

less

like the evolution of

has produced tools that are more

the organs of animals. to

is

less.

tools are different

from the organs of animals.

They are not parts of his body. They are detachable. He can take them up and put them down. One day a man may fly in an airplane. The next day he may navigate under the sea in a submarine. So while the tool is specialized, man is not. As tools have changed, becoming more and more fit for special jobs, they have increased the number of jobs that man can do. So, while separate tools have become more and more more and more

fit

to

fit

to

do less and less, mankind has grown do more and more. 29

CHAPTER

From Hunting

to

II

Farming

Journey into the Past

WE know what kinds of tools were used in Europe 500 years ago because the people who lived

at that

time

described them in books that they wrote. But writing was

invented by the Sumerians in Mesopotamia about

first

6,000 years ago. So written records help us look back no

more than 6,000 years into the past. But before people knew how to write they were already making pictures. Paintings found on the walls of caves

France take us back as far as 20,000 years. Some of these paintings are of hunting scenes and

We can some

show very

in

clearly the

weapons

of the hunters.

see farther back, as far as 50,000 years, because

were already burydead. Because they thought that the dead would

of the cave-dwellers of that time

ing their

continue to live in another world, they put their tools into the graves also.

Some

of these graves with the tools in

But we have also found tools that are much older than 50,000 years. These older tools are dug out of the ground too. But they were not buried by men. They were buried by nature, under the mud and gravel dropped by streams, or under the dust and sand blown by the wind. That is how we know that crude stone tools were used by Peking Man in China about

them have been discovered by

30

scientists.

500,000 years ago, and by an even older ape-man in South Africa perhaps a million years ago.

who

lived

ground we find remains of man's dead have a way of seeing the past alive. There are parts of the world where people still live the way our

By digging

past.

But we

in the

also

ancestors did 20,000 years ago. of South Africa, the

and the Eskimos

Semangs

of

By

visiting the

Malaya

in Southeast Asia,

in the far north, scientists

to see the past in the present.

By

have been able

seeing the tools of these

tribes of hunters, they get a better idea of tools

were

like

Bushmen

what the old

and how they were used.

Food-Gatherers

Up how

to

about 7,000 years ago, people had not yet learned

grow crops or raise livestock. They were foodgatherers. Nature grew the food for them without their help. All they had to do was take it. But it was not as easy as it sounds. Most plants are not good for food. Some are to

even poisonous. And animals don't sit around waiting to be taken. They either run away or fight back. Some of the larger animals could as easily eat a man as be eaten. So food-gathering was a difficult full-time job. People had to search for the that they

fruits, nuts, berries, seeds, leaves,

would

use.

They had

and

roots

to

hunt the animals that

kill

animals, and prepare

they would eat.

To help them

dig for roots,

food and clothing, these early hunters invented

many

tools.

Most of them were made of wood, stone, or bone. Wood and bone that lie in the ground for a long time decay and crumble into dust. So very few of the old wood and bone tools have been found. Only the stone tools have survived in large

numbers. That's

why

this early

period of

human 31

life is

called the Stone Age.

were food-gatherers, part, after

Some

is

The

called the

farming began,

is

when men Old Stone Age. The later

first

part of

called the

New

it,

Stone Age.

Old Stone Age were deThe digging stick was used for digging roots out of the ground. The hand-axe was used for cutting, chopping, and scraping. Then specialized stone of the

first

scribed in Chapter

tools of the

I.

and scrapers were made. In the final stages of the Old Stone Age they were attached to handles of wood and bone. tools like knives, axes,

Man

Extends His Reach

When

Stone Age

animals did not ran

sit

men went

hunting they found that the

quietly waiting to be killed.

They

usually

away long before the hunters were near enough to them with their axes. So the hunters had to find ways

strike

32

The spear extending man's reach. It was

of reaching the animals across a great distance.

was one

made

of the

of a long

first

tools for

wooden

pole, with a sharp point at

The point may have been cut from the wood

one end.

itself,

or

was

a piece of chipped stone attached to the wood. For hunting

and birds the Eskimos use a spear with many points on it, like a fork, to increase the chance of making a hit. To be able to throw a spear with greater force, some peoples used a spear-thrower like the one shown in the drawing. The bow was man's first invention for concentrating energy. When a bow is bent, all the energy used in bending it is stored in the springiness of the bow. When the bow is fish

(f