1893 the Bell Telephone Company owned 307,748
miles of wire, an amount increased by rival companies' property to
444,750. Estimates gave for that year nearly 14,000 "exchanges," 250,000
subscribers, and 2,000,000 daily conversations. New York and Chicago
were placed on speaking terms only three or four days before "Columbus
Day." All the chief cities were soon connected by telephone.

At the Philadelphia Exposition arc electric lamps were the latest
wonder, and not till two years later did Edison render the incandescent
lamp available.

The use of electricity for the development of power as well as of light,
unknown in the Centennial year, was in the Columbian year neither a
scientific nor a practical novelty. On the contrary, it was fast
supplanting horses upon street railways, and making city systems nuclei
for far-stretching suburban and interurban lines. Street railways
mounted steep hills inaccessible before save by the clumsy system of
cables. Even steam locomotives upon great railways gave place in some
instances to motors. Horseless carriages and pedalless bicycles were
clearly in prospect.

It was found that by the use of copper wiring electric power could be
carried great distances. A line twenty-five miles long bore from the
American River Falls, at Folsom, California, to Sacramento, a current
which the city found ample for traction, light, and power. Niagara Falls
was harnessed to colossal generators, whose product was transmitted to
neighboring cities and manufactories. Loss en route was at first
considerable, but cunning devices lessened it each year.

Thomas Alva Edison and Nikola Tesla were conspicuously identified with
these astonishing applications of electric energy. Edison, first a
newsboy, then (like Andrew Carnegie) a telegraph operator, without
school or book training in physics, rose step by step to the repute of
working miracles on notification. Tesla, a native of Servia, who
happened, upon migrating to the United States, to find employment with
Edison, was totally unlike his master. He was a highly educated
scientist, herein at a great advantage. He was, in opposition to Edison,
peculiarly the champion of high tension alternating current
distribution. He aimed to dispense so far as possible with the
generation of heat, pressing the ether waves directly into the service
of man.

[Illustration: Edison working in his laboratory.]
Thomas Alva Edison.
Copyright by W. A. Dickson.

[Illu