BOULDERS AND THE TRUE REEF. 17
surface;
but its dip can only be discovered by driving levels to intersect it at
depth. In fact, no so-called reef can be properly said to have been
proved until such levels have been driven, or shafts sunk upon it.
Nothing can be more deceptive than some of these heaps of quartz
boulders, particularly those found on low ground. They may prove on
examination to be no more than enormous masses of stone, detached ages
ago from a reef, and carried to their present situation by some
tremendous convulsion of nature, and subsequently, and by degrees,
partly buried in the earth. There are examples in the Wynaad of the
fall of a reef, and the consequent scattering of its fragments all over
the adjacent country. It is needless to say that mining operations
upon such detached boulders will result in nothing but disappointment.
It
is, I should observe, in determining the direction and the dip of a
true reef, that the skill and experience of the mining engineer are
called into play. Mistakes, in truth, may very easily be made. There is
an example of this on the very hill we are now exploring. Near the
summit and close to the outcrops, is an abandoned shaft, which had
been sunk some two years ago to a depth of about forty feet. It had,
however, been started on the wrong side of the dip. The deeper they
went, the further the reef receded from them; and the search was given
up in the belief that there was no reef here after
c
