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creek flows into the Meadows. Here some remarkably rich ground was
mined by Willoughby and others in the sixties. The ground gradually
deepened above and the water pressure was a serious obstacle to drift
mining, yet the difficulties were overcome and all of the channel, except
for a short distance in the upper part, was mined by drifting in the seventies
and eighties. The drifts were three or four sets wide in some places and
in others, where the channel is very narrow, only one set wide, and many
raises were made on the sides. Hydraulicking began in the nineties
and since that time nearly 8,000 feet of the channel has been completely
hydraulicked out. Hydraulicking was carried on for several years by the
Cariboo Consolidated Mining Company, Limited. In 1906 the property
was acquired by John Hopp and hydraulic operations, under the efficient
local management of Laurent Muller, have been continued each season
since that time. The property at the present time is probably the best-
equipped hydraulic mine in Cariboo. During parts of 1922, 1923, and 1924,
the grade of the sluice boxes in the upper 1,425 feet of the flume was
changed from a 6-inch (to the 12-foot box) to a 5-inch grade and the wooden
blocks throughout the flume, which is about 4,200 feet long, were replaced
by steel plates. The last of the steel plates were put in in August, 1924.
In hydraulicking out the channel bottom to permit of lowering of the grade
of the sluice boxes, which were in part a few feet above bedrock, consider-
able amounts of very coarse gold were recovered, showing how difficult
it is to recover all the gold in hydraulicking, unless the solid bedrock is
reached. The sluice boxes at the upper end are about 2 feet in the bedrock,
and there is little doubt that the bedrock will be held in extending the pit
upstream. Figure 16 shows the position of the head of the pit and of the
mouthpiece of the flume in August, 1921. In October, 1924, the head of
the pit at the surface was practically up to the lower dam and the mouth-
piece had been advanced upstream about 200 feet. The distance between
the head of the two pits was 2,700 feet. A cross-section at the head of the
Lowhee pit was approximately 30,000 square feet and at the head of the
Stouts pit 10,000 square feet. Taking the average cross-section of the
ground between the two pits as 20,000 square feet, the total yardage is
about 2,000,000 yards, or possibly 2,500,000 if the ground in the lower
part of Watsons gulch is considered. In the absence of borings the only
method by which the amount of ground available for hydraulicking can
be estimated is by assuming as above that the channel varies uniformly
in size between the two points where the size of the cross-sections is known.
The average gradient of the bedrock in the part between the heads of the
two pits is 4-5 per cent. As the gradient in the upper part of Stouts pit
beyond the summit is very slight, it is probable that the gradient increases
suddenly somewhere between the two pits. It is possible that the deep
channel of Lowhee gradually narrows and continues to Watsons gulch and
that there is an abrupt rise to the broad channel extending to the head of
Stouts. If so, the sudden increase of grade will be of value when the
hydraulic pit is extended upstream, in providing for a means of disposal
of the tailings and preventing an excessive length of sluice flume, which
is already very long and the up-keep expensive, and was especially so before
the steel plates were put in. The average length of the channel hydrau-
licked out yearly in recent years, except when the grade of the flume was