198 
GRAVEL ANT) PLACER MINING IN ALASKA. 
[BULL. 263. 
advisable. As used in remote districts in Siberia, the central shaft is 
frequently a wooden beam, and instead of the iron shoes, heavy stones 
dragged with chains, as in the arrastre, may supplant them. 
The above suggestions are made with reference to working the rich 
gravels of the shallow northern placers. Gravel containing less than 
$2 to the cubic yard is rarely worked by the method of the cable and 
Sections on line Y-Y 
| stee/ plate inclined toward 
~j shute with gradepf3"in 8'and 
[ punched with '/e"to l*'ho/es 
Fig. 44.— Modified Siberian pan for handling clayey gravel. 
traveling bucket. Lack of natural grade makes it necessary that the 
miner shall elevate his material, and the impossibility of getting water 
under head makes the use of steam power imperative. The point is 
that when such elevation is attained, it should be made available to 
thoroughly wash the gravel. At present this is not done. Perhaps 
the suggestions here offered may be of benefit to some operators. 
