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Cyclopedia of Telephony & Telegraphy Vol. 1 - A General Reference Work on Telephony, etc. etc. by Robert Millikan;Samuel McMeen;George Patterson;Kempster Miller;Charles Thom
page 43 of 497 (08%)
could be shaken by means of the diaphragm, and the resistance of the
line circuit varied in this manner. An early and interesting form of
such imperfect contact transmitter device consisted merely of metal
conductors laid loosely in contact. A simple example is that of three
wire nails, the third lying across the other two, the two loose
contacts thus formed being arranged in series with a battery, the
line, and the receiving instrument. Such a device when slightly
jarred, by the voice or other means, causes abrupt variation in the
resistance of the line, and will transmit speech.

Early Conceptions. The conception of the possibility and
desirability of transmitting speech by electricity may have occurred
to many, long prior to its accomplishment. It is certain that one
person, at least, had a clear idea of the general problem. In 1854,
Charles Bourseul, a Frenchman, wrote: "I have asked myself, for
example, if the spoken word itself could not be transmitted by
electricity; in a word, if what was spoken in Vienna might not be
heard in Paris? The thing is practicable in this way:

[Illustration: Fig. 4. Reis Transmitter]

"Suppose that 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 from a battery; you may
have at a distance another disk which will simultaneously execute the
same vibrations." The idea so expressed is weak in only one
particular. This particular is shown by the words italicized by
ourselves. It is impossible to transmit a complex series of waves by
any simple series of makes and breaks. Philipp Reis, a German, devised
the arrangement shown in Fig. 4 for the transmission of sound, letting
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