ngineer (to
whose courtesy I am indebted for these facts) tells me that he thinks
most of the water comes from the surface, and can be taken up in the
upper levels of the mine which is being worked at the depth mentioned. I
have given these details in order to show how enormous a mass of ore
remains to be extracted when the deep workings, which are still in their
infancy, have been fairly entered upon. But a still more remarkable fact
is that the auriferous banket beds appear, so far as they have been
followed by deep borings, to retain, as they descend into the earth, not
only their average thickness, but also their average mineral quality.
Here is the striking feature of the Rand gold-beds, which makes them, so
far as we know, unique in the world.

Everywhere else gold-mining is a comparatively hazardous and uncertain
enterprise. Where the metal is found in alluvial deposits, the deposits
usually vary much in the percentage of gold to the ton of soil which
they yield, and they are usually exhausted in a few years. Where it
occurs in veins of quartz-rock (the usual matrix), these veins are
generally irregular in their thickness, often coming abruptly to an end
as one follows them downward, and still more irregular and uncertain in
the percentage of gold to rock. For a few yards your quartz-reef may be
extremely rich, and thereafter the so-called "shoot" may stop, and the
vein contain so little gold as not to pay the cost of working. But in
the Witwatersrand basin the precious metal is so uniformly and equally
distributed through the auriferous beds that when you have found a
payable bed you may calculate with more confidence than you can anywhere
else that the high proportion of gold to rock will be maintained
throughout the bed, not only in its lateral extension, which can be
easily verified, but also as it dips downwards into the bowels of the
earth. It is, therefore, not so much the richness of this
gold-field--for the percentage of metal to rock is seldom very high, and
the cost of working the hard rock and disengaging the metal from the
minerals with which it is associated are heavy items--as the comparative
certainty of return, and the vast quantity of ore from which that return
may be expected, that have made the Rand famous, have drawn to it a
great mass of European capital and a large population, and have made the
district the object of political desires, ambition, and contests which
transcend South Africa and