be cheaper than gas, and also purer,
more steady, and more to be depended on. He rejected the principle
of the Voltaic arc involved in the Brush patent then in use, by
which the electric current was passed through a strip of platinum or
other metal that requires a high temperature to melt, because in
practice it was found that in fact, owing to the difficulty of
regulating the flow of the electric current, the medium did often
melt. He therefore sought for a medium that should be practically
indestructible, and believed that it would be found in pure carbon
enclosed in a vacuum. After many trials with one and another
substance, he at length found that by employing slender strips of
card-board reduced by intense heat to carbon, connecting them with
the wires leading from the machine, and enclosing them in glass
bulbs from which the air had been extracted, the desired result
could be produced. The next step to accomplish was the division of
the light, so that any number of lamps could be supplied by the same
pair of wires--a condition absolutely necessary if the invention
were to be of practical utility as applied to the lighting of
factories, public buildings, or private households, where-ever, in
short, many lights are needed. This was finally accomplished, and in
December, 1879, an exhibition was given at Menlo Park of a complete
system of lighting. This first demonstration of the possibility of
light-division created a great interest in scientific circles all
over the world, especially as scientific experts had testified
before the British House of Commons that the feat was impossible.
The Edison incandescent burner is now in use in every city, town,
and hamlet in this country, and it would seem as if it must of
necessity before long drive the costly, unhealthy, and dangerous
coal-gas out of use for illuminating purposes, although we believe a
wide field of usefulness lies before the coal-gas as a substitute
for coal in our kitchens.

Thomas Edison has received few public honors from his countrymen;
but the nature of his work has been such as to make his name a
household word throughout his native country; and not only by the
admiration excited by his genius--for it deserves no less a
name--but by the practical, every-day benefits he has conferred, he
has earned a place in the good-will and esteem of his fellows such
as seldom falls to the lot of man.

[Signature: Clarence Cook.]

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