secret, and, as Napoleon
refused to consider it, it never was put to a test. An Englishman
devised a frictional telegraph early in the last century and
endeavored to interest the Admiralty. He was told that the semaphore
was all that was required for communication. Another submitted a
similar system to the same authorities in 1816, and was told that
"telegraphs of any kind are now wholly unnecessary." An American
inventor fared no better, for one Harrison Gray Dyar, of New York, was
compelled to abandon his experiments on Long Island and flee because
he was accused of conspiracy to carry on secret communication, which
sounded very like witchcraft to our forefathers. His telegraph sent
signals by having the electric spark transmitted by the wire decompose
nitric acid and so record the signals on moist litmus paper. It seems
altogether probable that had not the discovery of electro-magnetism
offered improved facilities to those seeking a practical telegraph,
this very chemical telegraph might have been put to practical use.
In the early days of the nineteenth century the battery had come into
being, and thus a new source of electric current was available for
the experimenters. Coupled with this important discovery in its
effect upon the development of the telegraph was the discovery of
electro-magnetism. This was the work of Hans Christian Oersted, a
native of Denmark. He first noticed that a current flowing through
a wire would deflect a compass, and thus discovered the magnetic
properties of the electric current. A Frenchman named Ampere,
experimenting further, discovered that when the electric current is
sent through coils of wire the magnetism is increased.
The possibility of using the deflection of a magnetic needle by
an electric current passing through a wire as a means of conveying
intelligence was quickly grasped by those who were striving for
a telegraph. Experiments with spark and chemical telegraphs were
superseded by efforts with this new discovery. Ampere, acting upon the
suggestion of La Place, an eminent mathematician, published a plan for
a feasible telegraph. This was later improved upon by others, and it
was still early in the nineteenth century that a model telegraph was
exhibited in London.
About this time two professors at the University of Goettingen were
experimenting with telegraphy. They established an experimental line
between their laboratories, using at first a battery. Then Faraday
dis
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