Page 752

7352  GEOLOGY AND TOPOGRAPHY OF THE LEAD REGION.
There is another method by which drainage of mines has sometimes been effected,
and which might in many other places be employed to advantage. It is by simply
drill-
ing a hole from the bottom of the mine to some of the underlying clay beds
of the
Trenton. In this way a passage is often effected for the escape of the water,
of whichl
it will often avail itself until the opening becomes closed with niud from
the mine, when
a new hole has to be drilled.
In many portions of the Lead region, but more especially in the southern
and centra
parts, there is a desire which has often been earnestly expressed to me,
that a survey
should be made of the ore-bearing ranges both old and new. Such a survey,
to be of
any practical benefit, should be made with a transit and level, and with
the utmost
accuracy. It should be made underground when possible, and when not, it should
be
miade on the surface, locating the ranges from the shafts. The survey of
each district
should be referred to certain fixed points, whose location and elevation
should be accu-
rately ascertained. The location of these points with reference to each other
could at
any time be ascertained by triangulation if thought necessary. The whole
should then
be mapped on a suitable scale and published with the field notes.
The advantages derived from such a survey are chiefly the following: (1)
In ranges
which are now worked, it would be easy to reproduce on the surface the areas
worked
out below, and from the known course of the range the miner could, with considerable
certainty, locate his shafts so as to reach the unworked portions, thus effecting
a large
saving of tine, labor and money wasted in prospecting. (2) The surface of
the Lead
region is rapidly becoming an agricultural country. In many places the old
shafts are
being filled, the dump piles are being removed, and all surface vestiges
of once val-
uable ranges are becoming obliterated. Many of these ranges were worked many
years since for lead ore alone. to the natural water level, and abandoned
with valuable
bodies of ore still remaining in them; and in view of the increasing production
of zinc
ore, which is now between three and four times that of lead ore, it is not
unlikely that
it may become profitable to work them  again. From  a survey such as is outlined
above, the location of old shafts and ranges could at any tinme be restored.
(3) It would
conduce to the systematic working of the mines in the future, by forming
a basis to
which private surveys could be referred, and would indicate the points where
levels
could be most successfully placed for the drainage of the mines.
These are but a few of the advantages which will occur to persons actually
engaged
in mining. Probably there is enough money wasted in prospecting every year,
which
would be saved by such a survey, to carry it on to a successful termination.