Edison has taken out about fourteen hundred patents in the United States alone. He has not made all of these inventions himself. He worked like other inventors in his early days, doing all the work himself on whatever he had in hand, but for many years he has conducted a great factory, in which hundreds of men are employed, all busy on inventions. Just as other men conduct factories to manufacture, for example, automobiles, Edison conducts his factory to work out inventions. Most of the inventions attributed to him are, therefore, the product of his factory, rather than of himself alone.

The first patent taken out by Edison was in 1869, on a vote-recording machine. The machine was designed to secure privacy in voting, and to prevent fraud in public elections. The politicians did not want any such machine to come into general use, and the voters were not ready for it, so his first invention proved a flat failure. Edison, however, gained a valuable lesson from this experience. He resolved never to make an invention which was not wanted, and which could not be made a commercial success. From that day to this, before he undertakes an invention, he studies with great care the possible demand for it, the cost of making the invention, and the probable profits from its manufacture and sale. To this method of work is due much of his commercial success. But no small part of it is due to his industry and to his courage. He works as hard as any of the men he employs, often toiling for long periods, eighteen out of the twenty-four hours of the day. Then, too, it requires courage to invest great sums of money in new and untried things. The fine courage which sustained him during all these years was well illustrated when a great fire destroyed a number of his factory buildings. His answer to the wild flames as they leaped upon and ate up building after building was, "We will begin rebuilding to-morrow."

Of all Edison's inventions, in some ways the most valuable are his electric light, his phonograph, and his moving picture.

When Edison first exhibited his talking machine, in 1877, people hearing it repeat "Mary had a little lamb" deemed it a greater invention even than the telephone, and crowds filled great halls to hear the wonderful machine. The story went about at the time, that Edison gained the idea of the phonograph from accidentally pricking his finger. This is, of course, not true. The talking machine was the product of careful thought and hard work.

Edison first began to think of reproducing sounds mechanically, from reflecting on the record made on a disk by a needle attached to a telegraph key. From working with a phonautograph, the instrument used by Bell to record sound waves on a smoked paper, he conceived the idea of recording sounds on tin foil or on a wax disk, and then sending the needle back over the grooves to reproduce the sounds.

A phonograph is really only a phonautograph developed. The sounds to be reproduced are first recorded in grooves on a wax disk, by means of a phonautograph with a needle attached to the diaphragm. To reproduce the sounds thus recorded, the needle of the phonautograph is sent back over the grooves in the disk, and the sounds produced by the vibrating diaphragm are magnified by a horn-like arrangement. The phonograph is therefore a very simple mechanical contrivance to reproduce sound. It is, nevertheless, one of the most popular of modern inventions, as it has brought the music of the masters within the reach of the home, at small cost.

The moving picture, on the other hand, has done in part for the eye what the phonograph has done for the ear. As with some other great inventions, a popular toy was the forerunner of the moving picture. Some twenty years or more ago, it was possible to buy pictures of boys, in different positions, on a strip of paper stretched over a circular framework. By turning the crank the pictures were whirled around, making the boys appear to be playing leapfrog.

The first real moving pictures were of animals taken in motion. In working with these animal pictures, it was discovered that if they were passed before the eye at the rate of sixteen a second, instead of seeing sixteen pictures of the same animal in different positions, the animal appears to be moving. The moving picture is therefore nothing more than a number of pictures of the same object, animal, or person, in different positions, passed rapidly before the eye. The common rate of taking the pictures and of exhibiting them is sixteen per second. Edison took advantage of this peculiarity of our sight. He perfected the process of taking pictures of objects in motion, discovered the best materials for films, and worked out other practical details essential to good moving pictures. Few towns are now too small to have their "movies." Probably no invention is more popular, and surely none contributes more to the amusement of the public.

Edison, however, is to be thought of not only as an inventor, but also as a business man. Around and about his many inventions have grown great business enterprises, of which he is part owner. In these different enterprises are invested a total of almost seven billions of dollars, and in them are employed three quarters of a million men. To have set in motion such gigantic business enterprises, to say nothing of his great contributions to the comfort, pleasure, and amusement of nations, is in itself enough to rank Edison among the most distinguished of Americans.