for
the tunnel, at this depth, entered the blue ground 1134 feet from the
shaft, corresponding almost precisely to the distance from the mouth of
the shaft to the edge of the melaphyre at the
depth
of 300 feet. For hoisting service at this shaft, a winding-engine
plant was especially designed by the late Mr. Louis I. Seymour,
mechanical engineer for De Beers Consolidated Mines Limited, and
constructed by James Simpson & Co., of London, England. This plant
consisted of a pair of vertical tandem compound engines driving two
reels. These engines were designed to hoist six truck-loads in one
skip, from the 1000-foot level, in 45 seconds, including filling,
starting, stopping, and discharging;
