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 ofthe 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 hauling earth longer distances. For very short hauls, Charlie drove a fast little tractor. At least it looked small compared 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 away.
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 highway. 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 tractor.
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 another 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 guiding 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 andthe 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 theground, 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 covered 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 smooth.
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 wantedto, he could turn his seat sideways. Then he could easily see whether he was guiding the roller straight forward and straight back.
Many people call road rollers “steam rollers.” That’s because the first ones really were driven by steam engines. Men have a lot less fuss and bother with a modern 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 machines 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 theearth 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 machines 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 haulingMuskeg 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 uprightin 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 disappeared 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 derrick, 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 sometimes 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 bothkinds 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 bamboothat 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 refineries. 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 getting 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 hundreds of miles, inside the pipe, pushing out anythingthat 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 descendants 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.
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. Butthe miners still did all the coal digging and loading by hand.
Today many miners use power-driven drills for digging. 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 underground until it comes to the place where its operator wants to cut coal. He pushes a control, and the machine’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, pushing 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 customers. 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 unload 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 mouthful 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 electricity 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 sawmill.
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 stacks.
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, helooks 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 metal 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 television works also know how to make the most wonderful machines of all. Instead of saving muscle-power, these machines save brain-power. They solve very complicated mathematical problems at lightning speed. Infact, 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 mechanical 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 supposed 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 time.
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 marvellous 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 complicated 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 talking about people.
Some machines resemble animals in the way they look or the things they do, and so they have animal names. Besides 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 equipped with strong springs so it can hop over rocks or tree stumps, instead of getting caught on them.
SHEEP’S FOOT TAMPER—a heavy 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.
a,b,c,d,e,f,g,h,j,l,m,n,o,p,r,s,t,v,w.
airplane duster,26asphalt spreader,65bailer,34baler, automatic,26-27beet digger,42bit,69blower,28boom,9,49,51,55,74,85“box seat,”22bucker,53bulldozer,45,55,57,61,67,74,77bull wheel,73,74cable rig,72catcher,53caterpillar,45,46,60,67,68,74,77,85cats,68cement mixer,65chicken picker,24-25Chinese drillers,73-74chisel plow,32clamshell,49,84coal digger,81coal loaders,81coal mining,9,78-83corn cutter,25corn picking machine,21corn planter,19cotton picker,37-38cotton planter,37crane,10,49-52,54,85crawler tractor,45crawlers,10,48,49crowd shovel,49“cub” tractor,44cultivator,21cutter heads,15cutting head,81cyclone,39derrick,69Diesel engine,47dipper,49“dogging,”52dredges,14-15driller,72driverless plow,32-35earth mover,58egg machinery,24egg sorter,24electro-magnet,84escalators,83-84farm machines,18-45giraffe,83go-devil,77-78gooseneck trailer,48grader,61-64grass planter,26harrow,18hay baler,26-27hay blower,67hay rake,27hay stacker,28-29heater,53hoe, compressed air,36,37“hot-dope gang,”74house,49house moving,58jackhammers,12jib,52joint,70lumbering machinery,85-86magnet crane,84“making hole,”72manure scoop,24mechanical mouse,89milking machine,29-32mining, machinery78-83motor grader,61-64,67motor scraper,57mowing machine,26Muskeg schooner,69nut harvester,41oil wells,69-74ore unloaders,84overhead crane,10“package job,”22piggy-back crane,10pile driver,13pipelines,74-78plow,17,18,32,33,34,35post-hole digger,16potato digger,42powder monkey,60power shovel,47-48pull-shovel,49pumps,78-80reaper,22,42rig,70ripper,61rivet gun,53rivet man,53road building machines,55-68rock crusher,12rock rake,60rotary rig,72rotolactor,30-32roughnecks,72scraper,61seed planter,67shovel,9,47-48,49signals,52,84,88silage blower,26skull cracker,54snow plow,45,67spraying machines,38-39spud,15squeezer,89steam engines,80steam roller,66steam shovel,47-48suction dredge,57tandem roller,65tassel picker,40-41television,88,89“thinking machines,”89tomato planter,22tongs,70tractor,17,18,44,45,58,61trailer houses,69tree-dozer,17tree-shaker,41trencher,74-77turntable,51turtle,89two-gang plow,18vacuum unloaders,84welding crew,74well drilling,69-74wheat planting machine,22windrower,27wrecker,54