diverting experience while it lasted. The excitement
over the phonograph was maintained for many months, until a large
proportion of the inhabitants of the country had seen it; and then the
show receipts declined and dwindled away. Many of the old operators,
taken on out of good-nature, were poor exhibitors and worse accountants,
and at last they and the machines with which they had been intrusted
faded from sight. But in the mean time Edison had learned many lessons
as to this practical side of development that were not forgotten when
the renascence of the phonograph began a few years later, leading up to
the present enormous and steady demand for both machines and records.
It deserves to be pointed out that the phonograph has changed little in
the intervening years from the first crude instruments of 1877-78. It
has simply been refined and made more perfect in a mechanical sense.
Edison was immensely impressed with its possibilities, and greatly
inclined to work upon it, but the coming of the electric light compelled
him to throw all his energies for a time into the vast new field
awaiting conquest. The original phonograph, as briefly noted above, was
rotated by hand, and the cylinder was fed slowly longitudinally by means
of a nut engaging a screw thread on the cylinder shaft. Wrapped
around the cylinder was a sheet of tinfoil, with which engaged a small
chisel-like recording needle, connected adhesively with the centre of
an iron diaphragm. Obviously, as the cylinder was turned, the needle
followed a spiral path whose pitch depended upon that of the feed screw.
Along this path a thread was cut in the cylinder so as to permit the
needle to indent the foil readily as the diaphragm vibrated. By rotating
the cylinder and by causing the diaphragm to vibrate under the effect
of vocal or musical sounds, the needle-like point would form a series
of indentations in the foil corresponding to and characteristic of the
sound-waves. By now engaging the point with the beginning of the grooved
record so formed, and by again rotating the cylinder, the undulations of
the record would cause the needle and its attached diaphragm to vibrate
so as to effect the reproduction. Such an apparatus was necessarily
undeveloped, and was interesting only from a scientific point of view.
It had many mechanical defects which prevented its use as a practical
apparatus. Since the cylinder was rotated by hand, the speed at which
the record was forme
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