The power of transmitting messages to any distance or place to
which a wire can be carried, and in a space of time too small to be
reckoned, is without doubt one of the most wonderful inventions ever
carried out by men’s hands. Although the signals are carried from
place to place with a rapidity almost incredible, yet the electric
fluid travels at a certain, although marvellously rapid rate. It is
thought that light and the electric fluid both travel at the same
rate, namely, 192,000 miles in a second, and if so, a message might
be sent round the world (were it possible to carry on a wire) thrice
in that small space of time.