signal towers were erected from which flags were waved and various
devices displayed. Flags answered the purposes so very well that they
came into general use. In course of time they were adopted by the army,
navy and merchant marine and a regular code established, as at the
present time.

The railroad introduced the semaphore as a signal, and field tactics
the heliograph or reflecting mirror which, however, is only of service
when there is a strong sunlight.

Then came the electric telegraph which not only revolutionized all
forms of signalling but almost annihilated distance. Messages and all
sorts of communications could be flashed over the wires in a few minutes
and when a cable was laid under the ocean, continent could converse
with continent as if they were next door neighbors.

The men who first enabled us to talk over a wire certainly deserve our
gratitude, all succeeding generations are their debtors. To the man
who enabled us to talk to long distances without a wire at all it would
seem we owe a still greater debt. But who is this man around whose
brow we should twine the laurel wreath, to the altar of whose genius
we should carry frankincense and myrrh?

This is a question which does not admit of an answer, for to no one
man alone do we owe wireless telegraphy, though Hertz was the first
to discover the waves which make it possible. However, it is to the
men whose indefatigable labors and genius made the electric telegraph
a reality, that we also owe wireless telegraphy as we have it at
present, for the latter may be considered in many respects the resultant
of the former, though both are different in medium.