Near the bottom of the
shaft, branches are taken off to supply light to the principal roadways
and to the haulage engine-room, the main cables being carried into one
of the sections of the mine a distance of half-a-mile. After a careful
inspection of the lamps at the pit bottom, the party were photographed
in three groups, with the aid of the electric light, by Mr. Annan, of
Glasgow, who may well be credited with the distinction of being the
first to exercise his skill in the bowels of the earth. They were
then led to the haulage engine-room and into the workings, where they
witnessed the effects of the light. At the latter point, while, of
course, the visitors were at a safe distance, a shot was fired, bringing
down a large mass of coal. Having spent fully an hour below ground, the
party returned to the surface.--_Colliery Guardian_.
* * * * *
LIGHTNING AND TELEPHONE WIRES.
M. Bede, of Brussels, has an article in _L'Ingenieur-Conseil_ on the
above subject. He considers that a system of such wires forms the best
and most complete security against lightning with which a town can be
provided, because they protect not only the buildings in which they
terminate, but also those over which they pass. At each end they
communicate with the earth, and thus carry off safely any surplus
of electricity with which they may become charged.
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