the same instant, each set of
instruments depending on its selective note, while any intermediate
office could pick up the message for itself by simply tuning its relays
to the keynote required. Theoretically the system could be split up into
any number of notes and semi-tones. Practically it served as the basis
of some real telegraphic work, but is not now in use. Any one can
realize, however, that it did not take so acute and ingenious a mind
very long to push forward to the telephone, as a dangerous competitor
with Bell, who had also, like Edison, been working assiduously in the
field of acoustic and multiple telegraphs. Seen in the retrospect, the
struggle for the goal at this moment was one of the memorable incidents
in electrical history.
Among the interesting papers filed at the Orange Laboratory is a
lithograph, the size of an ordinary patent drawing, headed "First
Telephone on Record." The claim thus made goes back to the period
when all was war, and when dispute was hot and rife as to the actual
invention of the telephone. The device shown, made by Edison in 1875,
was actually included in a caveat filed January 14, 1876, a month before
Bell or Gray. It shows a little solenoid arrangement, with one end
of the plunger attached to the diaphragm of a speaking or resonating
chamber. Edison states that while the device is crudely capable of use
as a magneto telephone, he did not invent it for transmitting speech,
but as an apparatus for analyzing the complex waves arising from various
sounds. It was made in pursuance of his investigations into the subject
of harmonic telegraphs. He did not try the effect of sound-waves
produced by the human voice until Bell came forward a few months later;
but he found then that this device, made in 1875, was capable of use as
a telephone. In his testimony and public utterances Edison has always
given Bell credit for the discovery of the transmission of articulate
speech by talking against a diaphragm placed in front of an
electromagnet; but it is only proper here to note, in passing, the
curious fact that he had actually produced a device that COULD talk,
prior to 1876, and was therefore very close to Bell, who took the
one great step further. A strong characterization of the value and
importance of the work done by Edison in the development of the carbon
transmitter will be found in the decision of Judge Brown in the United
States Circuit Court of Appeals, sitting in Boston, on
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