two years, swept the country from end to end and made the radio receiving set known to millions. After his failure to interest Westinghouse, De Forest continued to perfect his apparatus. His greatest difficulty now was in convincing people that wireless was anything more than an interesting scientific toy. In January, 1904, he set up two transmitting stations at the Louisiana Purchase Centennial Exposition, at St. Louis, with receiving stations at Chicago and Springfield, Illinois. These were tested out by the Jury of Awards, with every precaution against fraud. Everything worked perfectly. It was the longest distance that messages ever had been transmitted over land by wireless, up to that time. De Forest sent messages for people who had friends in Springfield and Chicago, and these messages were exhibited as great curiosities. At the end of the exposition he was awarded the gold medal, diploma, and the first prize over two competitors, Marconi and the German Telefunken system. All this time he never had lost sight of his old idea of a "heated gas" detector. And now, for the first time, he was able to go ahead with his experiments on a substantial scale. He soon reached the conclusion that although a flame detector, on the order of the Welsbach burner, was perfectly possible, it was impractical because of the difficulty of carrying a supply of gas; so he turned to the idea of heating the gas in a closed glass tube by means of an electric filament. In 1905 he discovered the principle of the "audion" vacuum tube that is in general use to-day. It was patented in 1907. In 1906, he began working on the idea of transmitting the voice by wireless. It had been discovered that the flame of an arc light could be used to produce radio waves, and that these waves would carry the human voice. In that year the yacht "Thelma," belonging to W. R. Huntington, of Elyria, Ohio, was equipped with a radiophone for the purpose of reporting the yacht races at Put-in-Bay on the Great Lakes. It was the first vessel to be thus equipped. The transmission of voice and phonograph music was entirely successful, and this was the end of skepticism as to the practicability and value of radio. The successful equipment of the "Thelma" brought an order from Uncle Sam to install radiophones on the ships of the Atlantic Squadron, then under the command of Admiral "Fighting Bob" Evans. Most of the millions of broadcast listeners in the United States heard broadcasting for the first time in 1921. Few had heard it, or even heard of it, before then. And yet the first broadcasting was done thirteen years before that time in De Forest's experimental studio in New York. The first artist to sing over the radiophone in De Forest's laboratory to an unseen audience was Mme. Mazarin, Oscar Hammerstein's dramatic soprano. That was in 1908. Appropriately enough, she had been brought to New York to create the title rôle in the new opera, "Elektra." As far as is known, the audience was confined to one little group of listeners in Newark, New Jersey, and to ships in the harbor. There were only a few receiving sets in the United States then, outside of the government stations. No one suspected the immense possibilities of profit broadcasting would bring to the manufacturers of instruments. Far from being welcomed, the new art met with opposition. The newspapers commented languidly on it, and government and commercial station operators not only did not care for the music, but objected fiercely to the "jamming" of their signals. Within the past two years there have been thousands of requests from broadcast fans all over the country for opera broadcast from the famous Metropolitan Opera House, New York. For various reasons these requests have been refused. Yet, as far back as the winter of 1908-1909 an installation was made by De Forest in the Metropolitan Opera House. The long and costly litigation. While he was in straits for money he was offered $50,000 for the amplifier rights and, later, $90,000 more for an unlimited license to manufacture and sell the tubes, which he accepted. His remaining rights in the patents of his inventions he sold a year or so later for a little more than a million dollars. He is a long way, now, from the eightdollar-a-week youth who haunted the free-lunch counters in Chicago to save a dollar or two with which to buy materials. Although De Forest is less than fifty years old his hair is snow white, and his spare figure still shows the privations he went through in pursuit of his idea. But he is still inventing. He is working now on what he considers his second most important invention, the "phono-film," an arrangement by which an ordinary motion-picture camera will record sounds while making a picture. The moving picture of a band, for example, will be accompanied by an exact reproduction of the music it is playing. AUTHORITIES This life-story of the inventor appeared in The American Magazine for February, 1924, under the pen-name of Owen MacLean and is here reproduced by permission of both author and publisher. |