In Professor Bell's telephone a plate of sheet iron is made to vibrate
by means of the electrical current, something after the manner of
the skin of a drumhead. In a recent improvement by Mr. G. B. Havens,
Louisville, Ky., the electrical wires are wrapped around a common tin
fruit can. By means of tin cans at each end, sounds, it is said, were
sent over 92 miles of wire, and included several pieces of music.
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MR. HOTCHKISS, an American inventor, whose improved revolving cannon
we illustrated some time since, has received intimation that his
system has been approved by the French Government, and that they have
decided to adopt his cannon.
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