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Copyright 1953 by Ducnewald Printing Corporation. 
Lithographed in the United States of America. 




By Mary Elfing 





You could do everything that the machines 
in this book do. For some of the jobs, of course, 
you d have to get friends to help you. But people 
have always been able to work and build wonderful 
things, using just their muscles. And they can do a very 
great deal more when they use their brains, too. They 
can invent machines to make work thousands of times 
easier and faster. 

The big machine in the picture is a shovel that's 
used for digging an enormous hole. In one bite, its 
scoop can tear out a chunk of earth more than twice 
as tall as a man. Its long arm, called the boom, lifts the 
load as high as the top of a seven story building, then 
swings around and drops it almost a city block away. 
There are only a few shovels like this in the world. 
They were especially made to work where beds of coal 
lie close to the surface of the earth, covered by a layer 
of soil. The shovels clear away the soil so that other 
machines can dig out the coal. 


When a giant shovel has cleared off one spot, its 
crawlers begin to turn, and it creeps slowly ahead. But 
it can't travel on roads. It's far too big and heavy and 
tall — so big, in fact, that it came to the mine in sepa- 
rate pieces. Forty-five freight cars were needed to haul 
all the parts for just one machine from the factory to 
the mine. Then experts put the parts together right 
where the shovel was to start digging. 

And dig it does. In one minute its scoop can bite 
out as much dirt as 3,600 men could dig just using 
their muscles to lift ordinary hand shovels! 

The giant shovel is one of the biggest machines 
ever made, but there's another that can lift even bulkier 
things. It is an overhead crane that works in a shipyard. 

Often the crane hoists big boilers out of ships so 
that repair men can work on them. It is so huge that 
it carries another crane on its back. The piggy-back 
crane — that's its real name — reaches down and lifts 
things off the deck of the ship, too. 

Hammering is another kind of muscle work that 

machines can do quickly and easily. Suppose the water 
pipes under your street need mending. Repair men 
have to tear up the pavement in order to reach the 
pipes. So they bring in jack hammers to do the pound- 
ing. Strong blasts of air run the hammers, and, in no 
time, the pavement is broken up. 

Crushed rock was used for making the paved street 
in the first place. It came from a big machine called a 
rock crusher, which breaks up chunks of stone into 
small pieces. Strong jaws inside the crusher chew 
at the stone until they have made it into bits that are 
just the right size. 


An even bigger 
pounding machine is 
the pile driver. It can 
hammer a great thick 
log down into the 
ground almost as easily 
as a man can hammer a 
nail through a board. 
One kind of pile driver 
does its pounding job 
with a steam piston. 
Another kind lifts a 
heavy weight and lets 
it bang down on top of 
the log, called a pile. 
The one in the picture 


works in a harbor. It drives piles deep into the earth 
that lies under water. A whole group of piles make 
the foundation for a pier in the harbor, for ships to 
tie up alongside. 

Harbors and rivers must be kept safe for ships. If 
mud and sand pile up in a thick layer on the bottom, 
ships may get stuck. So dredges go to work clearing the 
mud and sand away. Often a clean-up job takes a long 
time. The men who run the machinery live on board 
the dredge, just as sailors live on a ship. 

Some dredges have scoops that dig under water. 
Others, like the one in the picture, use giant suction 
pumps. The mud or sand they suck up is called spoil. 


If there's hard-caked mud on the bottom, cutter 
heads break it up. Then it's ready to be pumped out 
through huge steel pipes that stretch away from the 
dredge like a great snake and pour the spoil out on land. 

Of course, a dredge must stay in one place while 
it is working. So it carries along two huge spikes called 
spuds. These move straight up and down at the stern 
of the dredge. When they ram into the earth under- 
water, they keep the dredge from drifting. 

A spud is so heavy that it pokes its own hole in the 
muddy bottom of a river or harbor. But making holes 
on dry land is a different problem. For instance, you 
can't just poke a telephone pole into the hard ground. 


or pound it in easily with a pile 
driver, either. So, in many 
places, a machine bores holes 
for telephone poles, just the 
way a carpenter bores a hole 
with a brace and bit. Then the 
machine's long arms reach out, 
lift a pole into the air and plug 
it down neatly into place. 

Long ago our ancestors dis- 
covered how to use simple tools 
— such as hammers, shovels, 
crowbars and rollers. These 
things seem very ordinary to us, 
but they were really wonderful 
discoveries. The clever men 
who invented them were pro- 
viding ideas, one by one, which 
scientists and engineers used 
much later. Our great machines 
are combinations of many, 
many things that men discov- 
ered from using simple tools. 


The giant shovel digs; the overhead crane lifts; the 
pile driver pounds. All machines multiply the power 
that's in the muscles of men — or of animals. The 
pushingest animal is an elephant. In some places in the 
world, elephants are trained to clear land by putting 
their foreheads against a tree and heaving until the tree 
topples over. 

A tree-dozer can out-push an elephant. The one in 
the picture has a special forehead built in front. With 
a slow, steady shove, it clears the way for roads or 
opens up fields for farms. 

Farmers used to dig their fields by hand. Then they 
hitched horses to plows. Now a tractor does the work, 
but we still measure its strength in horsepower. 



Dan is a farmer. He knows how to use almost any 
kind of farm machine, and he has lots of them. The 
most important is his tractor, for it is busy all year 
round. Sometimes it pushes. Sometimes it pulls. Or it 
may stand still and lend its power to other machinery. 

When the frost is out of the soil in the spring, Dan 
backs his tractor into the tool shed and bolts on a plow. 
This one is a two-gang plow — it can make two fur- 
rows in the earth at the same time. Dan touches a lever. 
The blades of the plow lift up so they can't dig into the 
farmyard and the road, and Dan chugs off to the field. 
Another touch on the lever sends the blades down. In 
a few minutes, Dan has made the first furrows across 
the field. 

Now he has to turn. He lifts the plow and steps on 
the left brake pedal. While the big left wheel stands 
still, the right one keeps going and turns the tractor, 
ready to start the next furrows. When Dan wants to 
stop, he steps on both the left and right brake pedals 
at once. 

After plowing comes harrowing. The tractor pulls 
a different implement for this job — a whole row of 
saucer-shaped metal discs that chew up the soil and 
spread it out evenly. Now Dan is ready to plant corn. 



The corn planter does five jobs in one trip down 
the field. It makes trenches for two rows of corn. It 
drops corn seeds into the trenches. It drops fertilizer 
alongside to give food to the young plants. It covers 
the seeds. And it leaves a mark all along the field to 
show exactly where the tractor should go to plant the 
next row of seeds. Dan follows the mark very carefully. 
All the rows must be exactly the same distance apart, 
because the tractor will have to go through the field 
again to cut out the weeds after the corn starts to grow. 
If the rows are badly spaced, the tractor wheels will 
squash some of the plants. 


when Dan was a little boy, he used to help his 
father hoe the corn by hand, getting rid of weeds and 
loosening the soil. Now he has an implement called a 
cultivator which does the job. 

After the corn is well up, Dan pulls the cultivator 
through the field, driving carefully, with the wheels 
between the rows. Small blades on the cultivator cut 
through the weeds and break the soil into loose chunks. 
The pictures show several kinds of cultivator blades. 

All summer long the corn grows tall. Dan waits till 
the ears are dry before he harvests them, ready for his 
cows and chickens to eat in winter. 

Dan's farm is small, so he can't afford to buy a big 
corn-picking machine. But his neighbor Al has one that 
he rents out, and one morning Dan drives it to his 



cornfield. His tractor seems lost inside the picking 
machine. Gatherers that look like the pointed snouts of 
huge mice creep along in front of the tractor close to 
the ground. One by one the stalks of corn go into the 
machine, which snaps the ears off. Then revolving claws 
and rubber paddles rip off the husks, and an elevator 
carries the clean ears back to a wagon which the tractor 
pulls along. In a very short time, Dan's whole field is 

Corn isn't the only thing that grows on Dan's farm. 
He raises tomatoes for the market, too. At planting 
time, he needs two helpers who ride on little seats very 
close to the ground behind the tractor. They put the 
tender little tomato plants one by one into a trench 
which the planting machine digs, and then a special 
wheel covers the roots with earth. 

Dan has some wheat fields, too. In the spring, after 
the ground is harrowed, a wide planting machine sows 
many rows of wheat at a time. And it drops out ferti- 
lizer to feed the plants on the same trip. 

Many farmers use their tractors for harvesting 
wheat, but Dan doesn't. Instead, he rents a shiny red 

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reaper which he calls a "package job," because it moves 
itself along and does the whole harvesting at once. It 
cuts the wheat, shakes the grain loose from the stalk 
and separates it from the husks. If there are weeds grow- 
ing in the wheat, the machine separates the weed seeds 
from the wheat kernels and spills them into different 

Dan sits high in the air at the front of the machine. 
He says he has a ''box seat.'' Behind him on a bench sits 


a helper who ties the bags as they fill up and puts new 
bags in place. Dan says it won't be long before some- 
body invents a machine that will reap the wheat, grind 
the flour and bake bread right there in the field! 

All of Dan's machines are wonderful inventions, but 
they can be dangerous, too, if people are careless. To 
give himself and his helpers warning, he has painted 
bright stripes and markers around open places where 
fingers might get caught in moving parts. 

Dan has a flock of fine white Leghorn chickens. He 
takes care of them by machinery, for eggs are a crop, 
too. The hens live in cages with wire floors, so that they 
keep very clean. All their droppings go through the 
wire to a platform below. With a special scoop, run by 
his tractor, Dan cleans the manure from the platform 
and puts it in a pile to be used as fertilizer on the fields. 

Every day the chickens have their meals brought to 
them on a moving belt. The eggs they lay drop through 
their nests onto another belt that carries them away. 
Finally a machine sorts the eggs according to size, ready 
for packing. 

Some farmers raise chickens for the market. Of 
course, the feathers must be taken off after the chickens 
have been killed. There are machines for this, too. One 


kind has mechanical fingers that pluck the feathers as 
chickens go past on a moving belt. 

Dan's neighbor Al has a big dairy farm, with lots of 
cows to milk every day, and land enough to grow their 
feed. Besides his corn picker, Al has other special ma- 
chines. One of them cuts corn while it is still green, 
chops it up fine and loads it into a truck. The truck has 
a sort of cage over it to keep the corn from spilling out. 
Next, Al turns his tractor into a stationary engine which 



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runs a blowing machine. A wide belt from a pulley on 
the tractor turns the blower, which shoots the chopped- 
up corn to the top of a storage tower called a silo. The 
green stuff ferments in the silo and turns into wonder- 
ful food for the cows. 

AFs fields are so big that he needs larger plows than 
the one Dan uses. He hires an airplane to spread dust 
that kills plant-eating insects. 

Al plants his hayfields with a seeding machine that 
he pulls behind the tractor. Grass seed is so tiny that it 
can't be planted deep. Al's seeder sprinkles just the right 
amount of seed on the soil, and then squeezes a thin 
covering of earth on top. He says the machine "tucks 
each seed to bed.'' 

After the mowing machine has cut the hay, Al pulls 
his automatic baler across the field. The baler scoops 
the hay up, then presses it into a box-shaped bundle, 




slices it off neat and square, and ties it 
with strong twine. One by one the 
bales drop out on the field, ready for 
a truck to pick them up. 

Some farmers rake their hay into 
long heaps called windrows before they 
bale it. The machine that does this job 
has many teeth that whirl round and 
push the hay sidewise into the wind- 
rows. The whole field has a rolling look, 
like ocean waves. 

The hay must be dry before it goes 
into the barn. If it isn't, it may get 
moldy. And green hay may even be 
dangerous. It can actually make heat 
enough to start a fire. 

To be sure his hay keeps well, Al 


has a blower that circulates air around the barn and 
dries the bales completely. 

Some farmers use machines that tie the hay into 
round bales. Others don't bale it at all. They use stack- 
ers to pile it into tall stacks where it is kept till the cows 
are ready to eat it. 

The stacker fits onto the tractor. When it was first 
invented, farmers thought it was a sort of luxury, be- 





cause it was used so seldom. Then they discovered that 
they could put it to work on other jobs, too. If a plat- 
form of boards is fitted across the forks of the stacker, 
it turns into an elevator that a man can stand on. Then 
he can paint the barn or pick apples from high branches 
without having to climb up and down ladders. 

It would take a lot of work to milk all of Al's cows. 
So he uses milking machines. When a man milks a cow, 
he squeezes with his fingers. Instead of fingers, the milk- 
ing machine has four soft rubber funnels that fit over 
the cow's teats. A pump squeezes the funnels, presses 
the milk out and sends it through hoses to the milk can. 

A farmer has only two hands. His milking machine 
has four funnels with hoses. So it can work much faster, 
and he can have several machines going at once. 

You'd never guess it, but a cow is a nervous, fussy 
animal. She lets down her milk easily if the same per- 


son or the same machine squeezes on her teats with the 
same rhythm every day, but any kind of change or 
hurry upsets her. Then she's hard to milk. And so Al's 
machine is built with a very accurate timer which makes 
the funnels squeeze exactly forty-eight times a minute. 

A good farmer tries to make life calm and comfort- 
able for his cows. Even the names for some things in 
Al's barn have a comfortable sound. The place where 
the cows wait to be milked is called the loafing pen. 
The room where they stand for milking is kept per- 
fectly clean, and it's called the milking parlor. 

Before the machine is attached, the cows' udders 
and teats must be washed clean. Al has fixed an upside- 
down shower bath for his cows. He built a concrete pen 
with sprays coming up through the floor. The showers 
clean^the cows and make them feel so calm that he 
never has any trouble milking them. 

The fanciest milking parlor of all has a machine in 
it called a Rotolactor. It is really a quiet, slow merry-go- 
round. Cows amble up a ramp and step into stalls on 
the gently moving platform. A man attaches milking 
machines to them, one after the other. By the time each 
cow has been carried halfway around the big circle, her 
milk has been pumped out into a glass tank that sits on 
a rack above her. A man takes off the rubber cups, a 

gate opens in front of the cow, and she steps off onto 
another ramp that goes from the center of the merry- 
go-round, underneath it and out to the barnyard. Twen- 
ty-five cows at a time can be milked on the Rotolactor. 

Automatic gadgets empty the milk from the glass 
tanks, wash them, sterilize them and get them ready for 
the next round. All the time men are busy keeping the 
stalls clean and tending to the machinery. Most dairies 
milk the cows twice a day, but the Rotolactor milks 
three times. 

The Rotolactor was invented for one particular 
kind of huge dairy. But farmers everywhere like to have 
good machinery to do special jobs. 

For hilly country, there's a plow that has one of its 
blades higher than the other so it can work on a slope. 
There are chisel plows that dig up hard soil by clawing 
at it with strong steel fingers. 

One farmer in Texas decided to make his tractor 
do the plowing all by itself, after he had driven it once 
around the field to give it a start. He invented a guide 



wheel that went ahead of the tractor in the furrow he 
had made. Now the guide led the tractor around in a 
spiral that got narrower and narrower until at last it 
stopped in the center of the plowed field. Another 

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Texan, with a bigger field and more machines, had a 
larger idea. He set three tractors loose without drivers, 
one behind the other. Away they went, round and 
round. If one traveled too fast and caught up with the 




one ahead, they stopped. The only work he had to do 
was go out and start them up again! 

There have even been experiments in guiding plows 
by remote control radio, the way airplanes can be 
guided. The farmer just sits under a tree and pushes 
buttons in a control box. 

Cotton is a crop that has always taken an enormous 
amount of work. Even after cultivating machines were 
invented, men had to go through the fields twice every 
year and hoe out weeds around the plants by hand. 
One farmer rigged up a contraption that made hoeing 

easier. He hitched an air compressor to his tractor and 
ran hoses from the compressor to four special hoes. 
Then the escaping air jiggled the hoes in the men's 
hands and saved the work of swinging them up and 

Nowadays some of the big cotton farmers have an 
easier way of solving the problem. They just keep the 
weeds from growing in the first place. As the planting 
machine drops the cotton seeds, it spreads weed killer 
along each side of the row. This killer is a particular 
kind of chemical that keeps the weeds from sprouting, 
but it does not hurt the cotton. The only weeds that 
grow in the field come up between rows where it's easy 
for a cultivator to scratch them under. 

At cotton picking time, machines now do the work 



in many places. Cotton is ready to pick when the little 
round heads of white fluff called bolls break open. Not 
all the bolls on one plant burst at the same time. A man 
who picks by hand can tell by looking which ones are 
ready. Of course the machine doesn't have eyes, but its 
tiny barbed steel fingers catch up only the opened 
bolls. The fingers are fixed on a turning drum. They 
pluck the cotton from the plant, carry it around to be 
pulled off and blown through a big pipe into a large 
basket behind the driver. 

People have been trying for at least a hundred 
years to invent a perfect cotton picker, and they 
haven't succeeded yet. The machines still can't do as 
careful a job as skilled men and women can do by hand. 

Nobody could possibly do by hand all of the spray- 
ing that protects farmers' crops. Mechanical sprayers 
come in many shapes and sizes. The most usual sort for 
big fields travels along behind a tractor, shooting chem- 
icals out from nozzles in a pipe that is twenty or thirty 
or even sixty feet wide. 

Some of the special sprayers are queer looking 
machines. One of them has six squirmy arms, bent in 
different directions so that they get the chemicals un- 
derneath leaves and on top as well. The kind that sprays 


fruit trees pumps chemicals out of twelve pipes at once. 
It works so hard and fast that farmers call it a cyclone. 
Then there is a sprayer that can be used for several 
different kinds of job. One day the farmer hitches it 
up to a tank near cattle pens. As the cattle walk down 
a narrow path between two fences, he sprays them 
with a chemical that kills bothersome insects. Next day, 
he may want to paint his fence. So he rigs the machine 
up differently and shoots paint onto the boards. 



All of this sounds as if everything that a farmer could 
need must have been invented by now. The fact is that 
there are new inventions coming along all the time, and 
farmers themselves make many of them. Every day in 
the week some farmer is likely to think up something 
he needs, then go to work making it. Here is a sample: 

Many farmers spe- 
cialize in raising a kind 
of corn called hybrid 
corn. In order to make 
it grow properly, they 
must pick the tassels 
off the tops of some of 
the corn plants. Each 
tassel has to be picked 
by hand, and it's a slow 
job in a big field. So 






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one farmer rigged up a machine that gives four tassel- 
pickers a comfortable ride all at the same time, and it 
gets the job done much more than four times as fast 
as before. 

It would take a whole book just to list the other 
machines that help different kinds of farmers. But here 
are some that are fun to know about: 

One clever contraption attached to a tractor grabs 
hold of nut trees and gives them a hard shaking. The 
nuts fall on the ground, ready for a kind of giant 
vacuum sweeper to come and suck them into a truck. 


Crops that grow underneath the earth need their 
own sort of harvesting machine. There are potato dig- 
gers and many others. The sugar beet digger works in 
a particularly clever way. Machine fingers feel for the 
beet tops. They set off a knife which cuts the tops off 
while other fingers lift the beet out and put it on an 
elevator which removes the clods of dirt as it travels. 
Once in a while the machine makes a mistake and de- 
livers a stone, or a chunk of mud at the end of the ele- 
vator. Men do nothing but throw the junk away and 
let the beets slide into the truck that travels alongside. 

A farmer always has to keep an eye on what his 
implements are doing, unless he has a helper who rides 
along on machines like this big reaper. When the trac- 





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tor pulls a cultivator or a planter, the driver must turn 
his head often to see how the work is going. For a long 
time, farmers complained that this was a pain in the 
neck, and they really meant that their necks hurt from 
turning so much. Some of them actually went back to 
using horses, because they could either walk or sit be- 
hind horse-drawn machines. So the farm machine 
makers had to change as many of the machines as they 
could, placing them beside the tractor or out in front 
where the driver can watch what is going on. 

Tractors themselves come in many sizes and shapes. 
Some are built very high off the ground so they can 
pass over tall crops without hurting the plants. Some 
have four wheels that can be pushed close together for 
work in one field and pulled wide apart for work in 
another. Some have three wheels. 

Mostly, farmers buy tractors the way people buy 
automobiles. They pick a model they happen to like 
and then argue that it's the best in the world. Of course, 
a little light ''cub'' tractor is easier to handle than a big 
one, but it can't do the hard work of a heavy model 
with huge rear wheels and tires. And here's something 
about the tires — farmers often fill them with water in- 
stead of air to give them more weight when they grip 
the ground. In winter, these farmers must put anti- 


freeze not only in the radiator 
but in the tires as well! 

On enormous farms where 
very heavy work must be done, 
there are often crawler tractors 
to do it. Instead of tires they 
have caterpillar treads that give 
a better grip on the ground. 
Then they can pull a whole 
string of plows the way you see 
them in the picture, staggered 
out behind. 

This kind of tractor was 
first named caterpillar by only 
one manufacturer. But people 
liked the idea, and they began 
to call all crawlers caterpillars. 

A caterpillar is powerful 
enough to push a snow plow, 
too. Or it can bulldoze out a 
hole for a watering pond or a 
cellar for a new building. 




Charlie is the man who can tell you about driving 
a caterpillar tractor. He works in a city, helping to put 
up big buildings, and he knows how to use other con- 
struction machines, too. In fact, Charlie grew up with 
machines, for his father and his uncles and his grand- 
father were construction workers. It often happens that 
families pass along their knowledge of building from 
the older to the younger men, and they are very proud 
of their skills. Charlie uses the caterpillar tractor with a 
bulldozer blade to push heaps of earth and rock into 
a pile, ready for the shovel to load on a truck. 

People often call the shovel a ''steam shovel/' but 
that's not its right name. You hardly ever see a real 
steam shovel any more. Years ago the big digging ma- 
chines were driven by regular steam engines. Before 
they could start to work on a job, the men had to build 
a fire in the boiler and wait until they had enough steam 
pressure to make the shovel go. Of course, this wasted 
a lot of time. So, when very strong gasoline and Diesel 
engines came along, builders began using them for their 
shovels instead of steam engines. 

Many shovels and other construction machines ride 
to work on long gooseneck trailers. They travel faster 
that way than they could on their own crawlers. And, 
in cities, the caterpillar treads might damage the pave- 
ment. To load and unload a shovel, the operator sets a 
short ramp of heavy planks against the trailer. Then the 
shovel creeps up and down on its own crawlers. 

The kind of shovel that's used on a job depends 
upon the work that must be done. If a basement has to 


be dug through hard rocky earth, Charlie may operate 
a crowd shovel, which crawls down into the hole. The 
shovel has a heavy dipper with teeth along the rim. 
When it digs, it crowds its teeth down into the ground. 
Charlie, sitting inside the cab, called the house, swings 
the dipper outward and up, then dumps the load into 
a truck. 

Another shovel digs in the opposite way. It's called 
a pull shovel. The teeth dig down and toward the 
driver. It can work from a bank and doesn't have to go 
down inside the hole at all. 

Sometimes Charlie uses a crane to get loose earth 
out of a hole. The crane has a long boom with wheels 
at the tip. Cables run over the wheels. Charlie fastens 
a kind of bucket called a clamshell to the cables. With 
its mouth open, the clamshell drops down over a heap 
of rocks and earth. Then Charlie starts machinery that 
pulls up on the cable. The jaws of the clamshell squeeze 
together and come up with a load of earth. Now Char- 



lie swings the whole crane around till the clamshell is 
hanging above a truck. He pulls a cable that opens the 
bucket, and the earth and stone tumble out. 

After the basement for a building has been dug, 
Charlie uses the crane for other jobs. Men hook the 
cables to heavy steel beams, and Charlie lifts them into 

No matter what he is doing, he has a lot to watch 
out for. He must know which of four brake pedals to 


use at any moment and which of four hand levers to 
pull. One lever works the turntable which swings the 
whole house around. One moves the boom up and 
down. The other two control the cables. 

At the same time, Charlie must watch what's going 

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on outside. A man stands on the job giving signals. 
Thumbs up mean 'Take the boom up.'' Thumbs down 
mean 'Tower the boom.'' When the signal man points 
up with his first finger, it means ''Raise the cable." If he 
wiggles the finger, it means "faster." When Charlie is 
lifting a beam and has to hold it for a while in the air, he 
says he "takes a strain and dogs it off." Dogging is his 
word for setting the brake on the cable. 

Things are always likely to fall around a construc- 
tion job, so the men who work on the ground have steel 
caps in their shoes to protect their toes. They wear steel 
helmets on their heads, too! 

As the building goes up, Charlie's crane lifts loads 
higher and higher. After a while he has to put a jib on 
the boom. This is an extension that makes it longer. 
When the building goes too high for his crane to reach, 
Charlie works another crane. It sits on top of the build- 
ing's framework and reaches down from there. 

After Charlie lifts a big steel girder into position, 
other men bolt it in place then fasten it tight with 


rivets. A man called a heater gets the rivets red-hot in 
a fire. Using tongs, he tosses them one at a time to the 
catcher who reaches for them — not with a mitt but 
with a kind of cup. The catcher pokes a rivet in a hole, 
and two other men fasten it tight. One of them, the 
bucker, holds the rivet in position with a bar, and the 
rivet man pounds the other end flat with a rivet gun. 
(The gun works like a jack hammer, and it makes an 
awful racket.) 

When you're down in the street, it's hard to realize 
that there may be a heavy wind blowing across the bare 
girders of a tall new building. High in the air, men have 
to keep their balance on narrow places and walk with 
sure feet. There are families who specialize in work far 
above the solid ground. Boys learn from their fathers 
how to walk safely without being afraid — although 
almost everyone is frightened at first. And, of course, 
everyone is careful. In New York a group of Mohawk 
Indians have worked on many high buildings where 
men like Charlie did the beginning work. 


Once in a while Charlie helps to wreck an old 
building before putting up a new one. First, a crew of 
men go in and take away everything that can be used 
again or sold for junk. With specially made crowbars, 
they pry away floors and door frames. They take out 
furnaces and plumbing fixtures. 
Then Charlie gets to work with 
his crane. At the end of a cable 
he fastens a heavy steel ball, 
called a skull cracker. Then, 


swinging the boom, he bashes the skull cracker into the 
wall of the old building. Over and over, the ball strikes 
the mortar and bricks. Cracks spread, and big chunks 
of the wall start tumbling to the ground. In a little while 
Charlie and his machine have made a heap of rubble 
out of a house that it took dozens of men to put up. 

Once Charlie worked on a road-building job. There 
he used a crane and a shovel and many other machines 
besides. This particular road had to cross a big swamp 
near the ocean. So the first problem was to fill up the 
swamp with something solid. In order to get enough 
earth and rock for the fill, men would have had to tear 


down a whole mountain. Instead they called in suction 
dredge machinery for the job. The huge pumps sucked 
sand from the bottom of the sea and poured it through 
pipes onto the swampy ground. When the water drained 
away, millions of tons of fine white sand were kft. 

Charlie helped level the sand off with a bulldozer. 
Then he moved on to a place where a hilly spot had 
to be leveled. There he drove a carrying scraper, a 
machine with a scoop between its front wheels and 
its rear wheels. The sharp scoop scraped up a load of 
earth, and Charlie drove off to dump it in a low spot. 
When he got there, a pusher blade at the back of 


the scoop pushed the earth out. Round and round he 
went, without having to stop for loading or unloading. 

Other men used a different machine like the one 
in the picture. This earth mover carried more in one 
load than the motor scraper, and it was better for haul- 
ing earth longer distances. For very short hauls, Charlie 
drove a fast little tractor. At least it looked small com- 
pared to the giant machines. It pushed a scoop in front 
of it like a shovel, then lifted a load, turned swiftly and 
dumped the earth where it was needed a few yards 

Charlie's road was going to be a special highway for 
speedy traffic. In order to make it as safe as possible, 
the crossroads had to be lifted up over the new high- 
way. Crews of men built these overpasses. First they 
used the huge earth-moving machines to make little 
hills on each side of the highway. Then they built 
bridges of concrete and steel between the hills. 

At one place, there were two houses on the exact 
spot where the hill for an overpass had to be made. 
Instead of tearing the houses down, moving men just 
carried them away with the furniture still inside. First 
they raised the houses off the ground with jacks. Next 
a tractor backed a wide, low trailer up close to each 
house. Using special machinery and rollers, the men 


eased the whole building onto the trailers. That same 
night, the houses were set down on new foundations, 
and the people went right on living in them. 

At one place, a big ledge of rock was in the way of 
the new road. Men called powder monkeys blasted the 
ledge to smithereens with explosive. Then Charlie came 
in with his caterpillar tractor and a rock rake. Unlike 
a garden rake, which you pull, Charlie's rock rake 
scratched up rocks and pushed them ahead of it. He 
shoved all the loose chunks of stone away, but several 
big ones were too far underground for the rake to pry 
them loose. So Charlie put a ripper on behind his 

The ripper had strong prongs that could dig down 
deep and get a good hold on a boulder. The frame that 
held the prongs was hollow. For very heavy work, 
Charlie filled the hollow frame with sand to give it a 
lot of weight so the prongs wouldn't slip. To pry out 
the very largest boulders, Charlie sometimes got an- 
other driver to hitch his caterpillar onto the ripper. 
Then the two tractors, chugging together, did the job. 

After the bulldozers and scrapers and rakes had 
built a rough bed for the highway, Charlie helped to 
smooth it down and get it all ready for finishing. He 
used a long six-wheel motor grader for the job. 

The motor grader had its Diesel engine in the rear. 


above the four wheels that did the pushing. The guid- 
ing wheels were way off at the front, and in between 
was the scraping blade, placed where Charlie could 
watch it. 

Charlie could set the blade at almost any angle, just 
as a barber can tilt a long-bladed razor. And Charlie was 
proud of the way he had left the road almost as smooth 
as a barber leaves a man's face. 

Charlie could play tricks with the motor grader's 
front wheels, too. Besides steering them in the ordinary 
way, he often made them lean over toward the right or 
the left. To look at them, you'd think they were 
broken, but they were only tilting to do a special job. 
They were actually in a tug-of-war with the blade and 


the earth it was pushing. The weight of the earth against 
the blade pulled the grader toward one side. But the 
leaning of the wheels pulled in the opposite direction. 
So the two pulls balanced each other. Charlie could 
guide the grader in a straight line without having a 
wrestling match with his steering wheel. 

Charlie leaned his wheels when the grader went 
around a bend in the road, too. They helped the long 
machine to turn easily. If he had to back into a ditch, 


he didn't worry. The great wheels adjusted themselves 
to the sloping earth. All six wheels stayed on the 

WSmSmU^gPf^SSS^x i uj~v,. ■ .,a-in--ju- 

ground, and the machine never got hung up the way a 
four-wheeled automobile would. 

When the earth had been smoothed down, it was 
time to put the hard surface on. Trucks brought in 
crushed rock to make a solid bed. Concrete mixers cov- 
ered the rock with concrete. And asphalt spreaders put 
a coat of asphalt on top. 

Wherever the asphalt wasn't spread evenly, men 
with rakes finished the job by hand. Then came the 
tandem roller to pack it down and make the surface 

A Diesel engine moved the roller's great weight 
quickly back and forth over the asphalt. In no time the 
road was as smooth as a table top. If the driver wanted 


to, he could turn his seat sideways. Then he could eas- 
ily see whether he was guiding the roller straight for- 
ward and straight back. 

Many people call road rollers ''steam rollers.'' That's 
because the first ones really were driven by steam en- 
gines. Men have a lot less fuss and bother with a mod- 
ern Diesel-engined tandem. There's no need to start the 
fire or shovel coal to keep steam up. You can still see 
some steam rollers at work, though, because they are 
strong machines that last a long time. But when one 
wears out, it is replaced with a modern roller. 

After the roller finished smoothing all the asphalt 
down, Charlie's road was ready for traffic, but the job 
still wasn't quite done. All along the highway the ma- 
chines had left bare banks of earth. These had to be 
protected from the weather — just the way a house is 
protected with a coat of paint. The best coat for the 


earth is grass of one kind or another. So Charlie turned 
gardener. In some places he used the motor grader 
again to prepare the soil so that seed could be planted. 
With the blade of his grader hung away out at the side 
and pointed up in the air, he smoothed off the steep 
banks. Running along the edge of the road, he filled in 
the soft shoulders. 

Then a seed-planter sowed the grass. And finally 
Charlie used the strangest machine of all. It chugged 
and puffed and spit out great mouthfuls of hay, which 
fell over the newly-planted grass! The hay protected 
the grass seed and kept it moist until its roots were 
growing strongly in the soil. 

The road was finished now, but some of the ma- 
chines still had work ahead of them. In fact, road work 
is never ended. 



All summer long, tractors pull mowing machines 
beside the highways, cutting the grass. Brush and small 
trees must be kept cleared away so that drivers can see 
ahead. In winter, the motor graders and the snow 
plows can keep the road clear. But in places where 
heavy snow piles up into drifts, caterpillar tractors often 
push special snow plows that eat through the drifts 
with powerful whirling blades. With one motion these 
plows dig out the snow and throw it off to one side of 
the road. 

The caterpillar treads work better in snow than 
wheels with tires. So the ''cats'' are used all winter long 
in the Far North. There they even pull whole trailer 
trains on runners. The one in the picture is hauling 

t i 

gi ^g^.:< 


Muskeg schooners, which are really trailer houses on 
sleds. Muskeg is an Indian word for swamp. The cats 
pull the schooners over frozen, snow-covered swamps. 

You may wonder why anyone wants to use a trailer 
home in the roadless wastes of the Far North. The fact 
is that men work there the year round, prospecting for 
oil. When they think they have located oil there or 
anywhere else, well-drilling machinery goes to work. 

Everybody knows that oil wells and derricks go 
together. The tall derrick towers are needed to hoist 
drilling equipment in and out of the hole. 

When men start to drill a well, they fasten a cutting 
tool, called a bit, to a piece of pipe which hangs upright 


in the derrick. Machinery turns the whole thing round 
and round, so that the bit grinds down into the earth. 
When one length of pipe, called a joint, has almost dis- 
appeared into the hole, men screw another joint onto 
the top of it. Now the engine turns the double-length 
pipe, and the bit digs down deeper. 

Men, working on the floor and high up in the der- 
rick, hoist more and more joints into position and screw 
them together as the bit goes on down. After a while, 
the bit gets dull. A new one must be put on. So, strong 
cables that run over wheels at the top of the derrick 
begin lifting the whole string of pipe out. Joint by joint, 
they unscrew the pipe and stack it out of the way. 
When the last joint comes up, men change the bit. 
Then back the pipe goes, joint after joint, into the hole. 

Wells must often be drilled more than two miles 
deep before the bit breaks through into an underground 
reservoir of oil. That means that the string of drilling 
pipe must be two miles long. The machines that help 
to handle it are very strong, but on many rigs, men 
have to use their own muscles a great deal, too. 

For deep drilling, the most modern rigs have a lot 
of fine new machinery. Automatic tongs take a tight 
grip on the drilling pipe when it is being unscrewed. 
Men used to work the tongs by hand. Mechanical hands 


now keep the bottom joints from dropping back into 
the hole, and arms high up in the derrick do the job of 
stacking the pipe. 

The skillful men who work with the pipes and the 
machinery call themselves roughnecks. The driller is the 
one who actually controls the drilling pipe. He never 
says he is digging a well. He says he is ''making hole.'' 

Almost all deep wells are now drilled by the turning 
pipe and bit, which are called a rotary rig. But some- 
times you can see an old-fashioned cable rig at work. 
It makes hole with a bit that pounds its way down into 
earth and rock. A cable raises the bit, and then lets it 
fall down with a bang that chips away a hole. On both 


kinds of rig, the hole is cleaned out with water. The 
water turns the rock dust into mud, which is then 
pumped out. 

The cable rig idea is about two thousand years old! 
That long ago Chinese drillers made water wells, salt 
wells and even oil wells. The picture shows what one of 
these ancient rigs was like. 

Look first of all at the long board attached to the 
rope that goes up over a roller and down into the well. 
Then look at the platform behind the board. Men 
jumped from this platform down onto the board. That 
jerked on the rope and pulled the drilling bit up in the 
well hole. When a man jumped off the board, the bit 
fell down and chipped away some rock. Round and 
round a whole crew of men raced, jumping onto the 
board and climbing back onto the platform as fast as 
they could. Still it took a long time to drill a well — 
sometimes as long as ten years. 

Now look at the big wheel turned by a bull at the 
right. This wheel lifted the pipe made of hollow bam- 


boo that you see at the left. The pipe was actually a 
bailer. Every once in a while the men poured water into 
the hole, let the bailer down and hauled up mud. Then 
the bit could go on drilling. Oil workers today still call 
the wheel which winds up cable ''the bull wheel.'' 

When a well brings in oil, a new group of men and 
machines go to work. They lay a pipeline, through 
which the oil can be pumped to factories called re- 
fineries. Some pipelines are hundreds of miles long. 

After surveyors have decided just where the line 
should go, bulldozers clear away brush, push over trees, 
heave big boulders to one side, making a wide pathway 
across country. In many places, the pathway is good 
enough for trucks to follow. They bring in lengths of 
pipe and lay them down end to end. Where the going 
is rough, a caterpillar tractor carries the pipe, one length 
at a time, hanging from a side-boom. 

Now welding crews go to work fastening the ends 
of the pipe-lengths together. When they have finished, 
the ''hot-dope gang" comes along. They are men who 
cover the pipe with a wrapping and then with a hot 
asphalt mixture to protect the metal. 

Meantime, a wonderful machine called a trencher 
has been at work. This is a cat attached to a rig which 


looks very much like an old-fashioned water wheel. 
Each bucket on the wheel has steel teeth. The cat turns 
the wheel and pulls it forward. The buckets scoop up 
earth, and spill it out onto a belt that dumps it in a 
heap at one side. The trencher plugs ahead, uphill and 
down, digging a ditch just the right width and depth. 

Following behind the trencher, cats with booms 
hoist up the snaky pipeline and ease it over into the 
trench. Finally, bulldozers backfill the trench. That is, 
they cover the pipe with the dirt that the trencher left 
alongside. On one job, the men had to work at top 
speed in the desert and in rocky, mountainous country. 
They were all so glad they'd finally succeeded in get- 
ting the pipeline built that they put on a celebration. 
Whooping and hollering, they tossed their sweat- 
stained hats into the trench in front of the bulldozer as 
it backfilled the last few feet of earth. 

Even after that there was one more tool that had 
work to do before oil could be pumped through their 
pipeline. It is a peculiar gadget that looks like a bunch 
of cowboy spurs hooked up with pieces of tin can and 
some old plates. The weird contraption is called the 
go-devil, and it has the job of traveling, perhaps hun- 
dreds of miles, inside the pipe, pushing out anything 


that could clog the line. Water pumped into the line 
behind the go-devil forces it through the pipe. 

In one line, the go-devil brought out chunks of 
wood, pieces of rock — and several rabbits, skunks and 
rattlesnakes that had decided the pipe would make 
good headquarters! Now the powerful pumps could go 
to work shoving oil through the line. 

Oil pumps today are much better and stronger than 
the first pumps ever built, but they are direct descend- 
ants of the ones that were invented for use in English 
coal mines long ago. In fact, those early pumps were the 
great-granddaddies of all modern machines. 

Wl 8S3S9ll4ltfMj^Bvf 


Coal miners in England had dug so far beneath the 
surface of the earth that the shafts and tunnels were in 
danger of filling up with water. Neither manpower nor 
the power of horses hitched to pumps could do the 
tremendous job of keeping the mines dry. Something 
much stronger was needed. In order to find a new kind 
of power, inventors began experimenting with steam. 
The first workable steam engines were made to pump 
out coal mines more than two hundred years ago. 

After a while steam engines began to pull trains over 
rails and drive ships through the water. They ran 
threshing machines on farms. Then inventors used their 
new knowledge about power to make other kinds of 
engines driven by gasoline or electricity or oil. 

At last some of this new machinery began to work 
its way back into the mines. Power driven elevators 
carried the men up and down shafts to their work. But 


the miners still did all the coal digging and loading by 

Today many miners use power-driven drills for dig- 
ging. Mechanical loaders pick up the loose coal and put 
it into small cars on the tracks in the tunnel. A little 
electric locomotive pulls the cars away to the elevator 
which hoists them up above ground. 

The most remarkable digger of all is the one you'll 
see on the next page. It rolls along a track deep under- 
ground until it comes to the place where its operator 
wants to cut coal. He pushes a control, and the ma- 
chine's long neck reaches up. The cutting head, at the 
end of the neck, starts biting into the coal. The head 
does its work much faster and easier than men with 
hand tools ever could. 

Outside the mine, machines sort the coal according 
to size and load it into railroad cars. 



Unloading machinery empties the cars in many 
places, too. There's one coal yard where a woman, push- 
ing buttons, controls machines that do everything — 
unload cars, store the coal according to its size in tall 
bins, and load the trucks that will deliver it to cus- 
tomers. This is how the yard works: 

Each railroad car empties its coal in a stream onto a 
moving belt. The belt carries the coal to a machine 
called a giraffe, which works like an escalator. The 
giraffe lifts the coal into a tall hopper. 

The woman who runs the coal yard sits in an office 
with a big window, where she can look out and see 
everything that's going on. When a truck has backed 
up to a hopper, ready to load, she pushes a button. Coal 
drops down out of the hopper onto another giraffe 
which lifts it into the body of the truck. As soon as the 
truck is filled, push goes a button and the loading stops. 



Moving belt machines work at other jobs, too. They 
load sand into trucks and cargo into ships. 

On some piers, huge vacuum cleaners empty ships 
full of sugar or wheat. At ports on the Great Lakes, 
machines reach down into ore-carrying ships and un- 
load them with great speed. At the end of each of these 
unloaders hangs a clamshell bucket. Just above the 
bucket is a little room where a man sits and watches 
what goes on. He signals to the operator, telling him 
just where to drop the bucket so it can pick up a mouth- 
ful of ore. The ship can be unloaded by two men who 
do nothing but signal to each other and push levers. 
But usually there are several machines working at the 
same time so that the job goes as quickly as possible. 

When iron ore has been turned into steel bars or 
wheels or gears, another kind of lifter can handle them. 
This one does its work with a huge electro-magnet that 
holds heavy weights when electricity is running through 
it. The operator drops the magnet onto the load of iron 
or steel that he wants to lift. Then he turns on the elec- 
tricity which makes the magnet and the piece of metal 
stick together. The operator moves the load wherever 
it is supposed to go. Then he turns off the electricity. 
The magnet lets loose and is ready for another job. 



Machines dug and loaded and delivered the coal 
that keeps your house warm. Machines helped cut the 
lumber that went into building your house, too. 

Far out in the woods, power-driven saws sliced 
quickly through the trunks of great trees. Caterpillar 
tractors hauled the logs out along rough forest trails. 

Perhaps the cats, using booms, lifted the logs onto 
extra-long trailers behind trucks and started them on 
the way to the sawmill. Or the cats may have snaked 
the logs to a river so they could float downstream to a 


No matter how the logs reached the sawmill, they 
were put at last onto belts which pushed them against 
huge whirling saws. A whole set of saws, all whining 
and screaming at once, turned the thick log into boards. 
Other machines planed the boards to make them 
smooth and then cut them to exactly the right sizes. 
Finally lift-trucks picked up 
great piles of board at once, 
whizzed them away and hoisted 
them elevator-fashion into high 




The operators of most machines sit where they can 
see what they are doing, or where they can get signals 
from helpers. But there is one that does things in a new 
way. Its operator just watches television in his cab. He 
never sees the parts of his machine at work. Instead, he 


looks at the television screen. A television camera on 
the roof of the building photographs what is going on 
below. This is what the eye of the camera sees: One 
machine that gathers up pieces of scrap metaf and 
dumps them into a squeezer; the squeezer that presses 
the scraps into neat bundles; a conveyor that loads the 
bundles into a railroad car. 

The operator watches the moving picture. Then he 
pushes levers that control the loaders and other levers 
that send a car on its way when it is full. The only thing 
he can't do is switch on a regular TV program and 
watch a show while he works! 

The time may come when people who operate 
other kinds of machines will find television helpful in 
many ways. Meantime, scientists who know how tele- 
vision works also know how to make the most wonder- 
ful machines of all. Instead of saving muscle-power, 
these machines save brain-power. They solve very com- 
plicated mathematical problems at lightning speed. In 


fact, they are called ''thinking machines/' They add, 
subtract, multiply, divide and do figuring that many 
college professors can't even do. 

Partly for fun, and partly to discover new things, 
the thinking-machine experts have also invented me- 
chanical animals. They've made turtles that can walk all 
around a room without bumping into anything. They've 
made a little wire-whiskered mechanical mouse that can 
actually sniff about until it finds something it is sup- 
posed to find — just the way a real mouse sniffs out a 
piece of cheese. The machine-mouse even ''remembers" 
where it went, and it runs straight to its cheese the next 

The machines you've read about in this book are 
mostly outdoor machines, operated by one man or a 
small crew of men. These are only a few of the mar- 
vellous inventions that you can find at work every day. 
Of course, there are hundreds and thousands of others 
in factories, making cloth, shaping automobile parts, 
printing books, doing the important work the world 
needs done. But, no matter how marvellous and com- 
plicated they are, they will never be as wonderful as the 
men who have invented them and built them and used 
them. When we talk about machines, we're really talk- 
ing. about people. 



Some machines resemble animals in 
the way they look or the things they 
do, and so they have animal names. Be- 
sides the caterpillar with its crawler 
treads and the crane with its long neck, 
here are some others: 
ALLIGATOR GRAB — a tool used to 
pick up things that get dropped 
into oil well holes. 
CAMEL-BACK CRANE — this one has 

a hump in its boom. 
FISHTAIL BIT — a drilling tool which 

is shaped like a fish's tail. 
KANGAROO PLOW — a plow equip- 
ped with strong springs so it can 
hop over rocks or tree stumps, in- 
stead of getting caught on them. 
road roller with spikes that pack 
earth down, the way a flock of 
sheep does. 
WORM LOADER — a long screw that 
twists round and round to push its 
load along. 


airplane duster, 26 

asphalt spreader, 65 

bailer, 34 

baler, automatic, 26-27 

beet digger, 42 

bit, 69 

blower, 28 

boom, 9, 49, 51,55, 74, 

"box seat," 22 
bucker, 53 
bulldozer, 45, 55, 51, 

6\, 67, 7 A, 77 
bull wheel, 73, 74 
cable rig, 72 
catcher, 53 
caterpillar, 45, 46, 60, 

67, 68, 74, 77, 85 
cats, 68 

cement mixer, 65 
chicken picker, 24-25 
Chinese drillers, 73-74 
chisel plow, 32 
clamshell, 49, 84 
coal digger, 81 
coal loaders, 81 
coal mining, 9, 78-83 
corn cutter, 25 
corn picking machine, 

corn planter, 19 
cotton picker, 37-38 
cotton planter, 37 
crane, 10,49-52,54,85 
crawler tractor, 45 

crawlers, 10, 48, 49 
crowd shovel, 49 
"cub" tractor, 44 
cultivator, 21 
cutter heads, 15 
cutting head, 81 
cyclone, 39 
derrick, 69 
Diesel engine, 47 
dipper, 49 
"dogging," 52 
dredges, 14-15 
driller, 72 

driverless plow, 32-35 
earth mover, 58 
egg machinery, 24 
egg sorter, 24 
electro-magnet, 84 
escalators, 83-84 
farm machines, 18-45 
giraffe, 83 
go-devil, 77-78 
gooseneck trailer, 48 
grader, 61-64 
grass planter, 26 
harrow, 18 
hay baler, 26-27 
hay blower, 67 
hay rake, 27 
hay stacker, 28-29 
heater, 53 
hoe, compressed air, 

"hot-dope gang," 74 
house, 49 

house moving, 58 
jackhammers, 12 
jib, 52 
joint, 70 
lumbering machinery, 

magnet crane, 84 
"making hole," 72 
manure scoop, 24 
mechanical mouse, 89 
milking machine, 29-32 
mining, machinery 

motor grader, 

61-64, 67 
motor scraper, 57 
mowing machine, 26 
Muskeg schooner, 69 
nut harvester, 41 
oil wells, 69-74 
ore unloaders, 84 
overhead crane, 10 
"package job," 22 
piggy-back crane, 10 
pile driver, 1 3 
pipelines, 74-78 
plow, 17, 18, 32, 33, 

34, 35 
post-hole 5igger, 16 
potato digger, 42 
powder monkey, 60 
power shovel, 47-48 
pull-shovel, 49 
pumps, 78-80 
reaper, 22, 42 

ri£j, 70 
ripper, b\ 
rivet gun, 53 
rivet man, 53 
road building 

machines, 55-68 
rock crusher, 12 
rock rake, 60 
rotary rig, 72 
rotolactor, 30-32 
roughnecks, 72 
scraper, 61 
seed planter, 67 
shovel, 9, 47-48, 49 
signals, 52, 84, 88 
silage blower, 26 

skull cracker, 54 
snow plow, 45, 67 
spraying machines, 

spud, 15 
squeezer, 89 
steam engines, 80 
steam roller, 66 
steam shovel, 47-48 
suction dredge, 57 
tandem roller, 65 
tassel picker, 40-41 
television, 88, 89 
"thinking machines,' 

tomato planter, 22 
tongs, 70 

tractor, 17, 18, 44, 45, 

trailer houses, 69 
tree-dozer, 17 
tree-shaker, 41 
trencher, 74-77 
turntable, 5 1 
turtle, 89 

two-gang plow, 18 
vacuum unloaders, 84 
welding crew, 74 
well drilling, 69-74 
wheat planting 

machine, 22 
windrower, 27 
wrecker, 54 

The author and the artist wish to thank the following for their help in making this book 
possible: Miss Elsie Eaves, Manager, Business News Department, l:.ncUnccrincl 7\'ews-Kt'cc>rd ,■ 
Margaret Gossett; Mr. Harold Spitzer,- Jbc Lamp, published by the Standard Oil Company 
(New Jersey); the Caterpillar Corp.; the General Motors Corp., the New Jersey Bel! Tele- 
phone Co.; the Florida Land Clearing Equipment Co.; the Walker-Gordon Laboratory Co.; 
the many manufacturers of digging, road-building and other specialized machines; a bumper 
crop of tractor and farm implement makers; and farmer friends who proudly showed their 
equipment in action. 



i .