connected with two different forms of Graham's patent safety air tight
contacts and switches for cutting off and letting on the current, the
effect of which, it is believed, would be to render the lamps quite
safe, even in the presence of explosive gas. At first the intention
was to employ the fan-engine to drive the dynamo-electric machine or
generator, but this was departed from, and an engine of 12 horse-power
was erected in the workshops on the surface for the purpose. From the
generator the electric cables, two in number, are conducted along the
roof of the workshops over ordinary telegraph poles to the pit-head at
No. 2 shaft, and thence down into the workings. From the ridge of the
workshops to the pithead, a distance of several hundred yards, the
cables consist of ordinary copper wire, three-eighths of an inch in
diameter; inside the workshop and below ground, to allow of their safe
handling, they are composed of insulated wires, while on the way down
the shaft they are inclosed in a galvanized tube. 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_.

* * * * *