62 
GKAVEL AND PLACEK MINING IN ALASKA. 
[BULL. 263. 
partially free, and little or no stripping was required. As a rule the 
scraper was found to clean the schist bed rock satisfactorily. The 
scraper used had a capacity of one-fifth cubic yard, being an ordinary 
horse scraper rigged for steam with pulling and drawback cables. A 
6-horsepower hoist operated the scraper, giving a capacity of 100 cubic 
yards in twenty-four hours. The 10-horsepower boiler also furnished 
steam to operate the bucket elevator which lifted the gravel to the 
sluice from the hopper, to which it was dumped by the scraper. A 
conservative estimate places the cost of handling gravel with rig, 3 
Pole/ 
§"sheave with !2"conic9l 
plate beneath 
'<?5 H. P. hoist s; '«a« 
'double drum 
Position of scraper can be 
j v altered by lengthening or 
^.shorten/ng line to anchor 
Anchor 
Fig. 7.— Set-up of scraper, Klondike. 
men being employed and one-half cord of wood burned in ten hours, 
at 40 cents per cubic yard. The operations were meeting with finan- 
cial success. 
The plant contains the elements of a device which, it is not unlikely, 
may be applied to the working of the wide, shallow creek deposits of 
Seward Peninsula, or of such creeks of the interior as Mammoth, in 
the Birch Creek district, or lower Pedro, in the Fairbanks district. 
If circumstances warranted, the sheave anchor (a rock-filled crib) 
shown in PL VI, A, could be made more easily movable by mounting 
it on a truck running on track, it being made fast by cable and dead- 
