Report of the Bureau of Mines of the Department of Internal Affairs of ...

386 REPORT OF THE INSPECTORS OF MINES. Off. Doc.
On my last ex-
ing, and electric machine cutters to do the mining.
amination of the mine I measured 20,000 cubic feet of air in circulation,
which was fairly well distributed about the face of the workings.
Drainage, I found much improved.
"Sterling No, 11."—The general condition of this mine is satisfactory
with but one exception, which is that the air should be split into
two currents. On my last examination, I brought this subject to the
attention of the foreman, and a plan was adopted by which the current
would hereafter be split. 1 would here state that I am not very
much in favor of splitting air currents in shallow mines, where but
from 90 to 100 men are employed and ventilation is produced by a
furnace with a shaft of 30 or 40 feet in height, a current of 10,000 to
12,000 cubic feet at the utmost being in circulation. A volume of
this size generally is much better not split, as the velocity is such
that after having been split it will not carry off the heavier gases and
powder smoke, but leaves the mine air continuously in a misty condition,
while this is not the case with one current, since the velocity
is so much higher and it carries away the smoke and heavier gases at
once.
•'Susquehanna."—When last examined, the condition of this working
was satisfactory as regards ventilation and drainage, the air
being well distributed and the water kept off the hauling roads. The
quantity of air in circulation was 10,200 cubic feet per minute.
''Allport."—This mine has been idle for some time, but was examined
about three weeks before it shut down and found in good
condition, the ventilation and drainage being carefully looked after.
''Summit."—The ventilation of this mine is up to the standard,
and all matters pertaining to the health, comfort and safety of the
employes are well looked after. The quantity of air in circulation,
on last examination, was 17,400 cubic feet per minute.
Carrolltown District.
"Elmoi-a Nos. 1 and 2" are the only mines in this disirici, the former
being on the B seam and the latter on the E seam. Both are operated
by the same company. The ventilation and drainage of "No. 1" I
found in a fairly good condition. In ''No. 2" the drainage in the
lower section of the work was somewhat defective, but the ventilation
was satisfactory. Both are ventilated by furnaces.-
Spangler District.
"Sterling No. i:>."—This mine was not ojieratt'd nearly (o lis cajKicit}"^
dui'ing the latter ])art of the year. On my last exaiiiination
about thirty-five men were employed. The ventilation and drainage
were in fair condition.