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floor of the tunnel and there is a 9-foot sump. It passed through 14 feet of
surface gravels and 58 feet of clay to bedrock. The total length of the
main tunnel is 250 feet. At 196 feet from the shaft channel gravels appeared
in the roof of the tunnel and extended for 40 feet. The tunnel was driven
beyond the channel in the hopes that another channel would be found,
but there is no doubt that the main channel was crossed. A drive up-
stream, starting at a point 225 feet from the shaft, was then made and
mining of the channel gravels begun. Mining was carried on during part
of 1922 by John McDougall and R. McDougall, and in 1923 by the two
McDougalls and Harold Mason. The drifts were carried upstream about
125 feet. In places the channel was very narrow, especially in the upper
part. In places in the lower part it was drifted three sets wide. One or two
of the sets (8-foot cap) produced as high as 7 ounces, but the average was
much less. Only about $1,700 in gold was recovered, and as the prospects
for higher returns in extending the drifts did not appear favourable, work
was discontinued in August, 1923. The mine was equipped with a water-
wheel for power purposes, and water was rendered available throughout
the year by a ditch 1,400 feet long from Jack of Clubs creek. At first the
water bailed from the mine amounted to about 40 barrels a day. Later,
the flow, which came mainly from the end of the main tunnel, amounted to
nearly 225 barrels a day. The flow of water, however, was easily con-
trolled by a continuous bucket-line hung in the pump chamber of the
shaft and operated by the water-wheel.

The grade of the bedrock in the deep channel of Jack of Clubs creek
along the part where mining has been done is somewhat irregular. In
sinking shafts along the sides of the valley for the purpose of mining the
deep channel the practice has been to determine the grade in the parts
mined from the elevations and depths of the old shafts and assume a
slight increase upstream or a slight decrease downstream. Irregularities
in the grade, however, cause serious difficulties, although there was no
difficulty in the case of the McDougall shaft, and the only sure way is to
determine the depth of the ground by drilling. The grade of the channel,
as determined from the elevations of the shafts and from the reported
depths to the channels near theshafts, is asfollows: between the McDougall
and Central 5-0 per cent, between the Central and Discovery 3-1 per
cent, between the Discovery and upper Sisters 3-5 per cent, between the
upper Sisters and lower Sisters 5-5 per cent, and between the lower Sisters
and Brothers 5-5 per cent. If the depth of the Brothers shaft is 180 feet
the grade between it and the lower Sisters would be 7 per cent, which
seems rather high. In any case a mistake was made in not sinking the
Brothers shaft deep enough, for the channel proved to be at least 20 feet
deeper than the bottom of the shaft. The unevenness of the grade renders
it difficult or impossible to correctly estimate the depth to the channel
in the lower part of the creek, even assuming that the reported depths of
the shafts are correct.

Two tunnels in the lower part of the creek, the upper one 300 feet
long and the lower one 400 feet, were run by William Brown in search of
clay in which to sink a shaft to the channel. Assuming a 5 per cent grade
for the bedrock from the Brothers shaft downstream, the depth to the

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