close of each day the gravel is drawn ; but all day long
the water that has poured through them has borne away
the yellow clay, not unmixed with a small percentage
of rubies. This clay is distributed outside the works,
and as it heaps up it makes a cone like that of a mud
volcano, furrowed and built up, and furrowed again,
by the water hastening on it£ way.
The motive power is electricity, and its Action is
communicated in the ordinary way by means of innumerable
wheels and endless leather bands. The whole
purpose of the machinery, which has been adapted from
that in use at the diamond mines at Kimberley, is first
UNDER SUPERVISION
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