tors enter into a comparison, however, for
machine-drilling produces a greater number of deeper holes and
permits larger blasts and therefore more rapid progress. In driving
levels under average conditions monthly footage is from two to
three times as great with heavy machines as by hand-drilling, and
by lighter machines a somewhat less proportion of greater speed.
The greater speed obtained in development work, the greater tonnage
obtained per man in stoping, with consequent reduction in the number
of men employed, and in reduction of superintendence and general
charges are indirect advantages for machine-drilling not to be
overlooked.

The results obtained in South Africa by hand-drilling in shafts,
and its very general adoption there, seem to indicate that better
speed and more economical work can be obtained in that way in very
large shafts than by machine-drilling. How far special reasons
there apply to smaller shafts or labor conditions elsewhere have
yet to be demonstrated. In large-dimension shafts demanding a large
number of machines, the handling of long machine bars and machines
generally results in a great loss of time. The large charges in
deep holes break the walls very irregularly; misfires cause more
delay; timbering is more difficult in the face of heavy blasting
charges; and the larger amount of spoil broken at one time delays
renewed drilling, and altogether the advantages seem to lie with
hand-drilling in shafts of large horizontal section.

The rapid development of special drills for particular conditions
has eliminated the advantage of hand-work in many situations during
the past ten years, and the invention of the hammer type of drill
bids fair to render hand-drilling a thing of the past. One
generalization is possible, and that is, if drills are run on 40-50
pounds' pressure they are no economy over hand-drilling.

WORKSHOPS.

In addition to the ordinary blacksmithy, which is a necessity,
the modern tendency has been to elaborate the shops on mines to
cover machine-work, pattern-making and foundry-work, in order that
delays may be minimized by quick repairs. To provide, however,
for such contingencies a staff of men must be kept larger than
the demand of average requirements. The result is an effort to
provide jobs or to do work extravagantly or unnecessarily well.
In general, it is an easy spot for fungi to start growing on the
administration, and if custom repair shops are available at al