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below Eightmile creek the valley widens, and gravel benches along the sides are continuous even in the narrow part above, and form marked features. At about 34 miles downstream the valley bottom is compar- atively wide and is partly blocked by morainic drift ridges which have diverted the stream and caused it to cut a rock canyon on the north side of the valley. About 2 miles lower down another rock canyon occurs. The creek has a fall of about 125 feet in the first mile below Eightmile creek and the total fall in 7 miles is nearly 900 feet.

Mining on Summit creek and its two main tributaries on the north side in the lower part, Sisters (or West) creek and Hobo gulch, has been carried on intermittently since the early nineties. Mining of the bench eravels at many places in the narrow part, and also in a few places in the wider, lower part, was carried on by ground-sluicing, and two fairly large hydraulic claims and one deep-drifting claim were operated for several seasons. The upper of the two hydraulic claims was known as the Victoria, the lower as the Van Winkle. The deep-drifting, or creek claim was known as the Juanita. All three were owned by the Colonial Mines Development Company of Canada, Limited, of which F. T. Hamshaw was superintendent. Mining operations were carried on from 1899 to 1901, when the Company passed into the hands of a receiver and operations ceased. The upper hydraulic pit is a short distance below the upper rock canyon on the creek and the lower pit about three-quarters of a mile farther downstream below where the stream takes a sharp bend to the north. The Juanita claim, on which a shaft was sunk to mine the deep channel, was at the lower end of the upper hydraulic pit. The shaft is on the right side of the valley flat, which is about 175 feet wide and about 75 feet below the general surface in the vicinity of the creek. Bedrock is exposed in places on both sides of the creek flat, but is mostly concealed by gravels and boulder clay, which vary in thickness from a thin layer:to 30 feet or more. John

_ Peterson, who worked in the mine, states that the shaft was 106 feet deep

to bedrock. The shaft was sunk, for the greater part of the depth, in partly cemented glacial silt which served admirably to keep out the water. Gravels containing some water were passed through near the bottom, but there was no difficulty in keeping the mine dry by pumping during the drifting operations. In all, about 575 feet of 4-foot tunnels were run from the bottom of the shaft, across the channel 175 feet and upstream, and eight blind shafts, the lowest being 30 feet, were sunk to bedrock in the channel, but it was not certain that the lowest part of the channel had been reached. Very little gold was found on bedrock in the channel and the tunnel gravels averaged only $1 to $4 a set. Water for hydraulicking was brought on the ground at the upper hydraulic pit by a ditch 25 miles long, from Summit creek, and at the lower pit by a ditch 2% miles long and about 1 mile of flume and 3,600 feet of pipe. Several monitors and double lines of sluice boxes, equipped with double undercurrents, were used in each pit. Mr. Hamshaw stated! that in 1901 a run of thirty-two days was made and 18,000 cubic yards of ground moved on the Victoria claim, and a run of twenty-six days made on the Van Winkle claim and 32,000 cubic yards of ground washed. The material washed was mainly the surface gravels,

1Ann. Rept., Minister of Mines, B.C., 1901, p. 735.