He was led
to conceive a similar apparatus by a study of the mechanism of the human
ear, which he knew to contain a membrane, or 'drum,' vibrating under the
waves of sound, and communicating its vibrations through the hammer-bone
behind it to the auditory nerve. It therefore occurred to him, that if
he made a diaphragm in imitation of the drum, and caused it by vibrating
to make and break the circuit of an electric current, he would be able
through the magnetic power of the interrupted current to reproduce the
original sounds at a distance.
In 1837-8 Professor Page, of Massachusetts, had discovered that' a
needle or thin bar of iron, placed in the hollow of a coil or bobbin of
insulated wire, would emit an audible 'tick' at each interruption of a
current, flowing in the coil, and that if these separate ticks followed
each other fast enough, by a rapid interruption of the current, they
would run together into a continuous hum, to which he gave the name of
'galvanic music.' The pitch of this note would correspond to the rate
of interruption of the current. From these and other discoveries which
had been made by Noad, Wertheim, Marrian, and others, Reis knew that if
the current which had been interrupted by his vibrating diaphragm were
conveyed to a distance by a metallic circuit, and there passed through
a coil like that of Page, the iron needle would emit a note like that
which had caused the oscillation of the transmitting diaphragm.
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