estimate the correct positions at which to place his drills and his
explosives. For this reason the work of the day must be systematically
divided so that at stated intervals the clay and other materials held
in suspension by the disturbed water may be allowed to settle and the
water be made comparatively clear.

Specially constructed strainers for the mechanical filtration of the
water near the ore face, and probably, also, chemical and other
precipitates, will be largely resorted to for facilitating this
important operation. Beside each window will be provided strong
flexible sleeves, terminating in gloves into which the miner can place
his hands for the purpose of adjusting the various pieces of machinery
required. Beyond this, of course, every possible application of
mechanical power operated from above will be resorted to, not only for
drilling, but also for gripping and removing the shattered pieces of
rock and ore resulting from the blasting operations.

From the unwatered drive or tunnel downwards, the method of working as
just described may be characterised as an underground application of
the "open-cut system". No elaborate honeycombing of the country below
the water-level will be economically possible as it is when working in
dry rock. But then, again, it is becoming plain to many experts in
mining that, in working downwards from the surface itself, the future
of their industry offers a wide field for the extension of the
open-cut system. In proportion as power becomes cheaper, the expense
attendant upon the removal of clay, sand, and rock for the purpose of
laying bare the cap of a lode at a moderate depth becomes less
formidable when balanced against the economy introduced by methods
which admit of the miner working in the open air, although at the
bottom of a kind of deep quarry. While the system of close mining will
hold its own in a very large number of localities, still there are
other places where the increasing cheapness of power for working an
open-cut and the coincident increase in the scarcity and cost of
timber for supporting the ground, will gradually shift the balance of
advantage on to the side of the open method.

At the same time great improvements are now foreshadowed in regard to
the modes of working mines by shafts and drives. Some shafts will in
future be worked practically as the vertical portions of tramways,
having endless wire ropes to convey the trucks direct from the face or
the