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Edison: His Life and Inventions

The Telephone, Motograph, And Microphone
A VERY great invention has its own dramatic history. Episodes full of human interest
attend its development. The periods of weary struggle, the daring adventure along
unknown paths, the clash of rival claimants, are closely similar to those which mark the
revelation and subjugation of a new continent. At the close of the epoch of discovery it is
seen that mankind as a whole has made one more great advance; but in the earlier stages
one watched chiefly the confused vicissitudes of fortune of the individual pioneers. The
great modern art of telephony has had thus in its beginnings, its evolution, and its present
status as a universal medium of intercourse, all the elements of surprise, mystery, swift
creation of wealth, tragic interludes, and colossal battle that can appeal to the imagination
and hold public attention. And in this new electrical industry, in laying its essential
foundations, Edison has again been one of the dominant figures.
As far back as 1837, the American, Page, discovered the curious fact that an iron bar,
when magnetized and demagnetized at short intervals of time, emitted sounds due to the
molecular disturbances in the mass. Philipp Reis, a simple professor in Germany, utilized
this principle in the construction of apparatus for the transmission of sound; but in the
grasp of the idea he was preceded by Charles Bourseul, a young French soldier in
Algeria, who in 1854, under the title of "Electrical Telephony," in a Parisian illustrated
paper, gave a brief and lucid description as follows:
"We know that sounds are made by vibrations, and are made sensible to the ear by the
same vibrations, which are reproduced by the intervening medium. But the intensity of
the vibrations diminishes very rapidly with the distance; so that even with the aid of
speaking-tubes and trumpets it is impossible to exceed somewhat narrow limits. Suppose
a man speaks near a movable disk sufficiently flexible to lose none of the vibrations of
the voice; that this disk alternately makes and breaks the connection with a battery; you
may have at a distance another disk which will simultaneously execute the same
vibrations.... Any one who is not deaf and dumb may use this mode of transmission,
which would require no apparatus except an electric battery, two vibrating disks, and a
wire."
This would serve admirably for a portrayal of the Bell telephone, except that it mentions
distinctly the use of the make-and-break method (i. e., where the circuit is necessarily
opened and closed as in telegraphy, although, of course, at an enormously higher rate),
which has never proved practical.
So far as is known Bourseul was not practical enough to try his own suggestion, and
never made a telephone. About 1860, Reis built several forms of electrical telephonic
apparatus, all imitating in some degree the human ear, with its auditory tube, tympanum,
etc., and examples of the apparatus were exhibited in public not only in Germany, but in
England. There is a variety of testimony to the effect that not only musical sounds, but
stray words and phrases, were actually transmitted with mediocre, casual success. It was
impossible, however, to maintain the devices in adjustment for more than a few seconds,
 
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