Page:Popular Science Monthly Volume 69.djvu/438

434 appeared to transmit most readily. "The particular instruments actually used were the 'membrane telephones' as transmitters and the 'membrane telephone' and 'iron box magneto receiver' as receivers." At the end of the week these instruments were replaced in the exhibit space in the gallery.

During that week thorough experiments were carried out and at their conclusion an award was made to Graham Bell by the judges of the group, while a special report drawn by Sir William Thomson, and a general report prepared by Professor Joseph Henry, secretary of the Smithsonian Institution and chairman of the judges, was published by the government.

Sir William Thomson said, in part:

In addition to his electric-phonetic multiple telegraph, Mr. Graham Bell exhibits apparatus by which he has achieved a result of transcendent scientific interest—the transmission of spoken words by electric currents through a telegraph wire. To obtain this result, or even to make the first step towards it—the transmission of different qualities of sounds, such as the vowel sounds—Mr. Bell perceived that he must produce a variation of strength of current in the telegraph wire as nearly as may be in exact proportion to the velocity of a particle of air moved by the sound; and he invented a method of doing so—a piece of iron attached to a membrane, and thus moved to and fro in the neighborhood of an electro-magnet—which has proved perfectly successful. . . . This, perhaps the greatest marvel hitherto achieved by the electric telegraph, has been obtained by appliances of quite a homespun and rudimentary character. With somewhat more advanced plans, and more powerful apparatus, we may confidently expect that Mr. Bell will give us the means of making voice and spoken words audible through the electric wire to an ear hundreds of miles distant.

The chairman, Professor Joseph Henry, in his official report, said:

The telephone of Mr. Bell aims at a still more remarkable result, that of transmitting audible speech through long telegraph lines. In the improved instrument the result is produced with striking effect, without the employment of an electrical current other than that produced by the mechanical action of the impulse of the breath as it issues from the lungs in producing articulate sounds. . . . Audible speech has in this way been transmitted to a distance of three hundred miles, perfectly intelligible to those who have become accustomed to the peculiarities of certain of the sounds. . ..

Another of the judges was Professor F. A. P. Barnard, president of Columbia College. A little later he publicly stated that

Of all instruments of precision and research which the group of Centennial judges was called upon to examine, there was none that occasioned greater interest or that they regarded as of higher novelty and importance than the speaking telephone of Professor A. Graham Bell,

and he was confident

that the name of the inventor of the telephone would be handed down to posterity with a permanent claim on the gratitude and remembrance of mankind.

Graham Bell was confident that he could transmit speech from Boston to Philadelphia, and, after his class examinations were over, he endeavored to secure the use of a telegraph circuit for that purpose, but failed because all 'were too busy.' Mr. Hubbard endeavored to