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it shows that the bedrock in the channel may slope towards Hightmile lake,
for the bottom of the shaft—and it may at one time have been deeper—is
practically at the same level as the bedrock in the hydraulic pit. In any
case the grade of the channel is so low that the hydraulic pit cannot be
extended much farther without losing the bedrock, except along the sides
of the channel. There is some gold, however, in the gravels along the east
side of the channel. Mr. Rees states that the gold is very unevenly dis-
tributed and is most abundant on bedrock and where the bedrock is hard
and uneven. In order to overcome the difficulty of disposing of the tailings
it was proposed at one time to drive a tunnel for about 2,600 feet up the
creek to the junction of the cross-channel, but the scheme was abandoned
as being too costly and not justified considering the small supply of water
available for hydraulicking, although the ground that was tested showed
values of over a dollar a yard in places. The extent of the ground, however,
and the average value are not known. The creek has a fall of 165 feet in a
distance of 4,500 feet in the narrow part, downstream from the cross-
channel. The amount of water available for hydraulicking, as estimated
from the drainage area and from the precipitation, is, on the average, about
100 inches for forty full days in the year. Using a No. 2 monitor under a
head of 100 feet the maximum amount of ground which could be moved
yearly would be about 7,200 yards, assuming good facilities for disposal of
the tailings.

The narrow, canyon-like part of the stream valley, like many other
rock channels in the area which are youthful as compared with the wider
channels of low gradient, such as the cross-channel, contained very little
gold. A shaft about mid-length of the canyon was sunk 27 feet to bedrock
through rock talus and boulders, a drive of about 300 feet upstream was
made, and the bottom of the channel was mined out in other places, but no
pay-streak was found. The canyon contained very little gold, apparently
because the only possible source was the small thickness of rocks cut
through and these were not gold-bearing. On the other hand the older
channels above the canyon represent stream courses of much greater age
which may have contained concentrations of heavy minerals such as gold
derived from the wearing away of a great thickness of bedrock. In the
bedrock gravels in the old channel at the hydraulic pit there are numerous
concretions of iron pyrites showing radiating structure from a central
nucleus. Some of them contain minute veins of quartz which show that
the concretions were formed in the bedrock and not in the gravels. They
were released from the bedrock by weathering and from part of the con-
centrates in the stream gravels. Most of the ancient concentrates in the
stream bed, however, were removed by glacial erosion, for the gravels in the
channel are practically all glacial gravels, so that the pay-streak is not
continuous, and the gold that remains is unevenly distributed. It is
possible, however, that a rich pay-streak occurs in places in the cross-
channel which appears to extend in the direction of the Thistle hydraulic
pit at Eightmile lake. If it extends to the pit, of which, however, there is no
very definite evidence, the thickness of the drift-filling of the valley on the
present summit between the two hydraulic pits must be at least 150 feet.

The Spruce claim, owned and operated by Mr. Mugfit, is located on a
short westward-flowing stream that joins Downey Pass creek about half a