199. The Wizard of the Electrical World. Thomas A. Edison was born in 1847 at Milan, Ohio. His father's people were Dutch and his mother's were Scotch. When he was seven years of age his parents removed to Port Huron, Michigan.

Edison owed his early training to his mother's care. At the age of twelve he was reading such books as Gibbon's Decline and Fall of the Roman Empire, Hume's History of England, Newton's Principia, and Ure's Dictionary of Science. The last-named book was too full of mathematics for him.

That Edison was a great reader is proved by his resolution to read all the books in the Detroit Free Library! He did finish "fifteen feet of volumes" before any one knew what he was doing.

In 1862 General Grant fought the terrible battle of Pittsburg Landing. Everybody wanted to hear the news. Edison bought a thousand newspapers, boarded a train, and the engineer allowed him a few minutes at each station to sell papers.

As the first station came in sight, Edison looked ahead and saw a wild crowd of men. He grabbed an armful of papers, rushed out, and sold forty before the train left. At the next station the platform was crowded with a yelling mob. He raised the price to ten cents, but sold one hundred fifty.

Finally he reached Port Huron. The station was a mile from town. Edison seized his papers. He met the crowd coming just as he reached a church where a prayer meeting was being held. The prayer meeting broke up, and though he raised his price to twenty-five cents he "took in a young fortune."

Edison began very early to make experiments in electricity. After rigging up a line at home, hitching the wire to the legs of a cat, and rubbing the cat's back vigorously, he saw the failure of his first experiment—the cat would not stand!

At Mt. Clemens, one day, young Edison saw a child playing on the railroad with its back to an on-coming freight train. He dashed at the child, and both tumbled to the ground at the roadside. For this act of bravery the telegraph operator gave him lessons in telegraphy.

200. Begins to Study Electricity. He studied ten days, then disappeared. He returned with a complete set of telegraphic instruments made by his own hand! After his trade was learned he began a period of wandering as a telegraph operator. For many boys still in their teens this would have been a time of destruction, but Edison neither drank nor smoked. He wandered from Adrian to Fort Wayne, Indianapolis, Cincinnati, Memphis, and Boston, stopping for shorter or longer periods at each place.

By the time he was twenty-two he had invented and partly finished his plan of sending two dispatches along the same wire at the same time. This was equal to doubling the number of wires in use.

Edison was a poor boy and was two or three hundred dollars in debt. He went from Boston to New York. The speculators in Wall Street were wild with excitement, for the electric machinery had broken down. Nobody could make it work. Edison pushed his way to the front, saw the difficulty, and at once removed it.

All were loud in their praise of Edison. On the next day he was engaged to take charge of all the electric machinery at three hundred dollars per month.

After a time he joined a company and gave his time to working out inventions. The company finally sent a number of men to ask Edison how much he would take for his inventions. He had already decided to say five thousand dollars. But when the men came he said that he did not know. He was dumfounded when they offered him forty thousand dollars!

201. Edison's Inventions. In 1873 Edison established his first laboratory or workshop in Newark, New Jersey. Here he gathered more than three hundred men to turn out the inventions pertaining to electricity which his busy brain suggested. They were all as enthusiastic over the inventions as Edison himself. No fixed hours of labor in this shop! When the day's work was done the men often begged to be allowed to return to the shop to complete their work.

Many telegraph and telephone inventions were made in this laboratory. There were forty-five inventions all told. They brought in so much money that Edison decided they must have a better place to work. He built at Menlo Park, New Jersey, twenty-four miles from New York City, the finest laboratory then in the world. On instruments alone he spent $100,000. In the great laboratory at Menlo Park Edison gathered one of the finest scientific libraries that money could buy. This library was for the men in the factory—to help them in their inventions and to give them pleasure.

The microphone is one of Edison's inventions. Its purpose is to increase sound while sending it over the wire. The passing of a delicate camel's-hair brush is magnified so as to seem like the roar of a mighty wind in a forest of giant pines.

Next came the megaphone, an instrument to bring far-away sounds to one's hearing. By means of this instrument, persons talking a long distance apart are able to hear each other with ease.

The phonograph, which can reproduce the human voice and other sounds almost perfectly, was invented by Edison in 1876.

Sounds reach the ear by means of air waves which the sounding body sets in motion. In Edison's first phonograph these waves struck a bit of taut parchment, and were marked by a needle on a tinfoil disc. But tinfoil does not hold its shape well. In 1888 Edison patented a better phonograph in which the record was made on a wax disc.

Phonograph records are now made with one hundred grooves to an inch. Each groove is not more than four one-thousandths of an inch deep. A lever tipped with sapphire cuts the grooves. Its tiny marks have been photographed—one way of seeing a sound!

The phonograph is used everywhere for amusement. It preserves the voices of great singers for the future. With it songs and bits of folklore can be collected in languages that are now dying out.

Edison has put into practical use many principles discovered by other men. He does not claim to be the discoverer of the electric light. He did much, however, to make it useful to people in lighting their houses, and also in lighting great cities.

In the winter of 1880, in Menlo Park, Edison gave to the public an exhibition of his electric light. Visitors came from all parts of the country to see this wonderful show. Seven hundred lights were put up in the streets, and inside the buildings. Edison had produced a much better light than any that had been used before.

202. A Great New Industry. Edison also had a part in another invention for which Americans can claim most of the credit—moving pictures.

A dispute about horseracing did most for the discovery of moving pictures. The question was whether a horse ever had all four feet off the ground at once. To settle it, Edward Muybridge, an employee of the government, was called in. He stretched cords, fastened to the shutters of a row of cameras, across a racetrack. As the horse ran past, it took its own pictures. Later Muybridge made a camera which would take pictures very quickly, but he could not show his pictures well.

Edison in 1892 invented a camera which used long strips of celluloid film. These pictures were looked at through a slot by one person at a time.

Another government worker, C. Francis Jenkins, invented the first complete moving picture machine in 1894.

At first people were slow to welcome the new kind of play. Now it is claimed that our fifth largest industry is moving pictures. Probably as many tickets are sold here each year as there are people in the world.

In the war each army had its own moving picture camera men. They took pictures of ships torpedoed, of airplane battles, and of the fighting among the icy peaks of the Alps, often at great danger to their own lives. Great events of world history like the signing of the armistice can now be recorded for future times. Such pictures teach us things that cannot easily be learned from books.

Many schools have a machine of their own, and use moving pictures as a part of their regular class work. The subject is first outlined, then the pictures are shown, and afterwards the pupils write about what they have learned.

Some schools have films of their own. Others find it easy to get them. Our government sends out educational films on silo building, dairying, airplane manufacture, and many government activities. Business firms have films to loan on shoes, soap, automobiles, and other things they make. Regular film companies have pictures of animal life, the natural wonders of our country, current events, foreign countries, and other subjects suitable for school use, such as the teaching of cube root by moving picture cartoons.

Outside of schools moving pictures can be used for educational purposes in social service and Americanization work. One state, North Carolina, has trucks carrying moving picture machines for many of its counties. Programs of educational and amusing pictures can be given regularly in small towns with these machines.

203. Christopher L. Sholes and the Typewriter. The typewriter cannot be called the invention of any one man. Many inventors, half of them Americans, worked on the problem, for even a simple machine has many parts.

Machines by which the blind could print or type raised letters were first made. A little difficulty may hold back a great invention. A typewriter was not built until long afterward because inventors did not know how to ink type.

In the Scientific American more than fifty years ago was printed an article on a new invention which was rather grandly called the "literary piano." Christopher Latham Sholes, a Wisconsin editor read the article. He was convinced that he could make a better typewriter than this himself.

He set to work, and his first typewriter was patented in 1868. It was indeed something like a piano. It had long ivory and ebony keys, but it also had a third set of peg-shaped keys like those we now use. It carried its type on levers arranged in a circle. It had a spacer, and a way to move the paper along as it was typed, as well as inked ribbon, which he borrowed from an earlier inventor.

Sholes' was the first successful practical typewriter made. Now nearly twenty million dollars' worth are produced in this country each year.

204. The Dictaphone in Business Offices. An interesting outgrowth of Edison's phonograph is the dictaphone, used in dictating business letters. It consists of two machines much alike. On the first are put smooth cylinders of wax. The person dictating speaks through a tube. Then the dictaphone operator puts the cylinders on her machine, places light tubes in her ears, and takes down the dictation on her typewriter as she hears it.

Both machines are run by electric motors, and that of the operator can be stopped with the foot. The wax cylinders may be pared and used again and again.

The dictaphone means a great saving of time and labor, for dictating can be done anywhere at any moment.

205. The Earliest Automobiles. The first kind of automobile men tried to build was a "steam carriage." A Frenchman in 1755 invented a steam road wagon meant to draw a field gun. But his invention could not be steered, and was soon wrecked by running into a wall.

In England one hundred years ago a few of these "steamers" were run as stage coaches. They were noisy, clumsy "steamers" and always likely to explode. They were not popular, and a law was passed that a man must always walk ahead of them carrying a red flag. They were only allowed to go only four miles an hour. Of course this meant they could not be used at all.

Oliver Evans of Philadelphia built the first steam automobile in the United States in 1804, to carry a steam flatboat he had made down to the river. Evans and other inventors after him for nearly one hundred years worked on self-driven carriages, but could interest no one in their plans. Watts, the great English inventor of the steam engine, stopped a friend who had all but invented an automobile. It was useless, he said; roads would not allow such rapid travel. Watts could discover steam power, but it never occurred to him that good roads could be easily built. The use of rubber tires in 1887 stopped the jolting that had been such a difficulty.

In 1892 Charles Duryea built the first gasoline automobile in America. He tried to get money to continue his work. He told a business man, "You and I will live to see more automobiles than horses on the street." The man thought him crazy, and refused to help him. Now horses are becoming rare in large cities.

206. America, the Land of Automobiles. In 1891 the first electric vehicle in this country was made. The first gasoline car was sold March 24, 1898. Now, twenty years later, this country is manufacturing nearly half a million cars annually. Other countries are backward by comparison. Four-fifths of all the automobiles in the world are owned in the United States.

Motor trucks can carry many tons, and are now very largely used for hauling, especially in cities. At the end of the war our government had seventy thousand trucks in use overseas.

One time when the German army threatened Paris it was only the unbroken stream of motor trucks moving along a great French road carrying men and supplies to the front that saved the city. In memory of its service the French call this road the "Sacred Way."

207. Early Attempts to Fly. To sail through the air as birds do is an ambition that has dazzled men since ancient times. The Greek myths tell us of Phaeton who drove the horses of the sun, and of Icarus who flew too near the sun with his wings of feathers and wax.

To learn how to fly men studied the wings of huge birds living millions of years ago, made careful mathematical reckonings about them, and then made themselves wings of feathers or skin. But with these wings they could only glide to earth from high towers or cliffs. One useful thing they learned from this study. They found that the wing of a bird is bent as you bend a long piece of paper if you hold it by opposite corners and start to twist it. This is called the principle of the screw, and is now used in making the propeller blades of airplanes.

208. The First Airplanes. Early airplanes, airplane models and "gliders" were made in the queerest, most outlandish shapes imaginable. They had from one to five or more planes, arranged at almost every possible angle. Some looked like a row of box kites, some like dragons, and some like a collection of old fashioned windmill wheels all fastened together.

It was only a little while ago that men were working with these strange models, for it was only about ten years before the World War that a successful airplane flight was first made.

The invention of the balloon came late in the history of flying. Two sons of a French paper manufacturer probably made the first balloon. They filled a large bag with hot air from a bonfire, and found that it rose and sailed away.

Early balloons were carried through the air by wind currents, and could not be guided. Their passengers were often blown out to sea and drowned.

A German, Count Zeppelin, invented a balloon called a dirigible, because it could be directed through the air. The Germans named these large cigar-shaped balloons "zeppelins," after their inventor.

Dirigibles are now built more than two blocks long, about the length of the largest battleships. They can lift heavy loads, but are very expensive and very easily broken, and require huge sheds or houses to shelter them.

An airship properly means a dirigible, while an airplane is a heavier-than-air machine. The first successful flight of any length in an airplane that could be directed was made by Wilbur Wright in 1903, at Kitty Hawk, North Carolina. It was also the first time an airplane had been driven by a gasoline engine.

209. The Wright Brothers. Wilbur Wright was one of two brothers who had long been working on the problem of a flying machine. He was born in 1867, and his brother Orville in 1871. Their father was a bishop whose excellent library took the place of a university education for his boys. Wilbur and Orville studied especially works on physics, mathematics, and engineering. They earned their living by making and repairing bicycles. But they spent much time experimenting with different kinds of gliders. They also studied the action of the atmosphere. AËrostatics, or the science of the air, is a very difficult and important part of flying.

Before Wilbur Wright's success in 1903 progress of various kinds had been made. Fairly long flights with gliders had been made in different countries. Two Americans, Langley and Hiram Maxim, had worked out models driven by steam. Langley's had flown half a mile over the Potomac, and Maxim's, though not allowed to fly freely, was strong enough to carry a man.

The Wright brothers were wise in employing a gasoline motor. A steam engine, with its large boilers, was of course much heavier. They had a rudder in the tail of their machine, but they also invented a new method of steering. By "warping" or bending the planes, a monoplane, with its one set of wings could keep its balance as well as a biplane, which has two.

After Wilbur Wright's first flight in 1903 several Frenchmen made successful flights. But in 1908 Wilbur Wright went to France and broke the records of all the French flyers by the unparalleled feat of remaining in the air for more than two hours.

Now the airplane can do all kinds of fantastic tricks. Aviators "loop the loop" dozens of times, and move in any direction through the air at will. They can rise in the air thirty-six thousand feet, and can fly at the rate of three miles a minute. In 1907 Orville Wright made the first record flight of an hour. All this has been accomplished in scarcely more than a dozen years since then. Flying developed especially rapidly during the World War. Airplanes were used to spy out the enemy's defenses, to direct gunfire, to drop bombs, to shoot down soldiers, and to hunt submarines. The daring and brilliant fighting of airmen in the World War makes a story more breathless than that of any novel. Incidents like landing with burning planes or with planes partly stripped of their canvas were not uncommon for these fighters of the air.

One type of airplane was used for fighting and another heavier type for bombing. Air bombing is now so accurate that in the future it may be useless to build super-dreadnaughts and large battleships.

210. Peace Time Uses of the Airplane. During times of peace airplanes are useful in exploring and for carrying passengers and light freight. Airplanes scarcely more expensive than the earlier automobiles can now be bought.

Airplanes in this country are chiefly used for carrying mail. "The mail must fly" is the slogan of the mailmen of the air, and in storm or fog—even in the face of a tornado—it has gone.

In May, 1919, a hydroplane belonging to the United States navy made the first trip across the ocean. A hydroplane is an airplane having a boat-like body so that it is able to alight on or rise from the water.

In July a British dirigible flew across with its crew. A few weeks earlier a British plane flew from continent to continent in less than sixteen hours. It took Columbus seventy days to make his crossing.

211. The Submarine. During the War of the Revolution an American named Bushnell worked on the problem of making a boat that would sail under the surface of the sea. He was the first to work on this problem and is called the Father of the Submarine. Some years later Robert Fulton (page 257) became interested in the submarine. In 1801 he built one for the French government. But Fulton turned his efforts to making steamboats and did not continue his plans for a successful diving boat.

212. John P. Holland. John P. Holland was born in Ireland in 1842. He was a studious boy and became a teacher. The stories of Bushnell and of Fulton interested him and he studied carefully what they had done.

He came to America and settled in New Jersey. There he got a position as teacher in a parochial school. He continued his study of the undersea boat making many experiments and tests.

Holland's first submarine became stuck in the mud. But he did not give up. His next boat he called the "Fenian Ram." It frightened people when it suddenly raised its head out of the water and as quickly disappeared.

In 1895, after a number of severe tests, Holland succeeded in interesting the United States Government in his plans. He built for it a submarine which he named the "Plunger."

Holland now formed a company to build his boats. In 1898 he produced the famous Holland submarine. This boat settled any doubt about what submarines could do. It was only fifty feet long, but it could dive under water and rise again at the will of the inventor. From that time the Holland company built many submarines for all the great nations of the world.

From the top of the submarine there extends upward a long slender tube called a periscope. When the boat is under water the end of this tube extends above the surface. By means of a certain arrangement of lenses and mirrors in this tube, the observer in the submarine can see everything on the surface of the water. In this way the boat can be guided in any direction.

Holland died in 1914.

213. The Submarine in War and Peace. The submarine is much used in war time. The war diver is provided with one and sometimes two tubes through which torpedoes or bombs may be fired at enemy ships while the submarine is hidden under water. It is very hard to detect a submarine when it is under the water. The only sign of its approach is a slight ripple on the surface. But if we look straight down at the water from high up in the air, then the outlines of the boat can easily be seen. In war time airplanes are used in spying out the submarine.

In times of peace, too, the submarine is of great value. It is not exposed to great storms on the sea, since it can escape the waves by submerging. These boats can cross the ocean and are large enough to carry cargoes of valuable goods. In July, 1916, the world was startled by the arrival of the merchant submarine, "Deutschland," at Baltimore. Loaded with articles of trade, mainly chemicals, she left Bremen, dodged the British and French blockade, and in fifteen days reached America.

One cause of America's entering the World War was Germany's attempt to starve England by a submarine blockade.

214. Other Inventions in the War. The "depth bomb" was an out and out new invention. 11 could be "dropped" over the spot where a submarine was seen. Very often it blew the submarine to pieces.

The "tank" was a "moving iron fort" drawn by a tractor. It could tear wire entanglements to pieces and cross enemy trenches. The "depth bomb" and "tank" were used mainly by the Allies.

The wide use of "poison gas" was first introduced by the Germans. Guns able to shoot many miles were invented. One of them carried seventy miles or more.

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