The weekly miner. [volume] (Butte, Mont.) 1878-1881, 1880-09-28
THE Light.

In an article i'll the Noith .4mericuu Re
uiew for October, Mr.. Edison gives the public
to understand that his electric light is by 10
means a failure, even if we have heard but
very little about it lately: With regard to
the delay experienced in submitting his latest
and most important invention to the test of
practical use, Edison very reasonably asks us
to consider the great difference between even
the most successful experiments of the labor
atory and the practical establishment, on a
commercial basis, of the resulting discovery,
and more especially when it is designed to
enter into competition with interests and in
luences so extensive as those of the great pas
companies throughout the Union. referring
to similar delays in the case of other and
highly important discoveries, the writer re-
minds us that the first photograph was not
taken until many years after the essential
principles of photography had become well
known that the steam engine was not in
vented unil long after meu had become ia
mliiar with the scientific principles involved
IN It's construc ion j.; and hat even when it
was invented long years passed before it was
successfully employed for purposes CT travel,
IN the steamboat aud locomotive. Finally,
when it Vas SO employed in an experiment
resulting in the fast running steamers. or
lightning express ulains of the present day, it
was in direct opposition to the opinion of sci.
entific men who were almost unanimous in
denouncing il as the hobby of a crack-brained
enthusiast, just as many of our sarunts are de-
%nouncing the electric light or rather the
principle involved in it, which is the djyisi-
bility OF the electric current. But Edison as
surcs us that the light Is a success, and fur.
tLer' hat it will be on trial in a very short
time, as all arrangements have been made for
a public demonstration to be given at Meplo
Park within the next two months. Follow
Ing the demonstration the electric light will
be Immediately offered for general use, and
first in the city of New York. The appara-
tus. as he describes it, consists in the first
place of a ''dy namo-machine" for generating
the requisite electricity. This machine is
worked by a l20 horsepower steam engine.
and is connected by wires with all the differ.
ent houses OF establishments which it is ta
furnish with electric illumination. Upon being
generated in the dynamo the current is diyid-
ed by a process not explained and sent cours.
ing along a multiplicity of wires to an cleo.
trio lamp at the extremity of each. The i'm.
proved electric lamp consists of an oval bulb
Of glass about five inches Ill height and having
a hollow stem through which two platinum
wires enter the cavity. On the inside the
wires are connected by a loop of carbon
whose incandescence is to furnish the light,
As soon as they are thus connected the air in
the bulb is exhausted by mercury pump n-
til not more than a one-millionth part remains,
when the stem is Theoretically sealed and the
lamp is fit for use. TO light it requires sim
ply that the platinum wires from the stem be
connected with the wire from the dynamo,
when the carbon burns with a clear, White
light, far steadier and less trying to the eyes
than the yellow, pickering light of gas. Burn
ing in a vacuum it is not consumed, the aver
age duration of carbon loop being 800 hours
or about six months use, four Or five hours