THE ELECTRIC TELEGRAPH NOW IN USE.

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INVENTION OF THE ELECTRIC TELEGRAPH NOW IN USE.

No one person can be strictly called the inventor of theelectric telegraph.

In order to ascertain whether the honour of this magnificentinvention can he ascribed to any one single person, let usdissect any of the forms of telegraph now in general use. Letus take, for example, the needle telegraph as now generallyused by ‘ The Electric Telegraph Company ’ in England, andby its dissected parts show to whom is due the honour of theinvention or discovery of each of its parts.

Yolta, in 1800, discovered the galvanic current.

CErsted, in 1811, discovered that a magnetic needle wasmoved by the passage of an electric current through an adjoin-ing wire.

Schwieger invented the coil.

Schilling, in 1832, placed the magnetic needles vertical.

Steinheil, in 1837, made the counting of the number of mo-tions the basis of his alphabets.

Sturgeon discovered and invented the electro-magnet.

Schilling, in 1832, used a weight which was caused to fallby a current of electricity to sound a bell.

Wheatstone and Cooke, in 1845, made a similar fallingweight to liberate wound-up mechanism, and thus to sound abell.

Early experimenters showed that glass, porcelain, andresin were insulators of electricity.

Watson, in 1747, sent currents of electricity through wiressuspended in the air on posts.

Steinheil, in 1837, used wires suspended in the air, andburied in the ground, for an electric telegraph.

Cooke, in 1842, patented a particular method of suspendingwires in the air, and a particular form of glass and porcelainfor insulators.

Watson, in 1747, showed that one-half of an electric currentmight be formed of the earth.