160 GRAVEL AND PLACER MINING IN ALASKA. [bull. 263. 
trically heated water thrown against the bank. The fact that hydrau- 
licking with water heated to 50° and applied directly to the face 
through a nozzle in Klondike drifting- operations is remarkably effective 
in thawing frozen gravel suggests possibilities in regard to dredging. 
This possibility is extremely remote, but might under certain cir- 
cumstances be applicable where the dredge is operated by electric 
power generated by water under head. 
The fact the dredge is the only appliance used in placer mining 
which transports its sluices and continually provides new room for its 
tailings renders it attractive in the consideration of the shallow north- 
ern placers. 
In Seward Peninsula there are some river deposits which contain 
gold sporadically distributed and in which frozen and unfrozen areas 
alternate. Extensive prospecting has resulted in the discovery of a 
certain amount of ground which appears to warrant the installation 
of dredges of special design. More of these areas may be found, and I 
it is probable that some of them may be in the interior. It is not 
believed that dredges can be operated successfully in any of the area 
included in the South Coast provinces, as there the geological condi- 
tions are almost the exact opposite of those outlined at the beginning 
of this section. 
DESCRIPTION OF OPERATIONS. 
Notwithstanding the difficulties encountered in the interior of 
Alaska, the possibility of dredging in this field under certain favor- 
able conditions is not to be denied. A small dredge for prospecting 
purposes was being operated cheaply in Stewart River in the Yukon 
Territory, not far from the international boundary, during the season 
of 1904. It subsequent^ operated in Klondike River. This dredge 
has 39 open connected 2i-foot buckets, and handles 750 cubic yards 
in twent}^-four hours. It digs to 30 feet, and in Stewart River very 
little frozen gravel was encountered. A crew of 6 men is employed I 
and the daity working cost alone is said to be 7 cents a cubic yard. 
The hull was built at White Horse, of 4-inch planks of imported! 
Vancouver fir, and cost $5,000. 
A complete description of this dredge has been published by the 
designer, Mr. A. W. Robinson." 
A dredging installation was also visited on Gold Run, in the Atlin 
district of British Columbia. The power plant was situated on Pine 
Creek, 5 miles below the dredge. A flume and ditch line 1£ miles 
in length supplied 1,500 inches of water, at 187 feet head, to 2 Victor 
turbine wheels of 500 horsepower each. It was said that 80 per cent 
of this efficiency was available at the dredge. The current was 
delivered at 1,100 volts to the transformer and this was stepped up to 
aThe Stewart River gold dredge: Canadian Mining Institute, March 4, 1903. 
