bitlNGTON.] 
OPEN-CUT MINING, 
65 
but only one cord of wood at $2 per cord was burned. The double 
irum hoist was provided with 10 by 12 inch cylinders and was geared 
> to 1. Four men, a winchman, a fireman, and two scraper men were 
smployed, at $2.50 a day. It was said that under these conditions 
the operations cost 5 cents per cubic yard. It was estimated that in a 
aaul of from 150 to 200 feet the scraper would deliver loam to the 
spoil heap at the rate of 2 cubic yards per minute. 
The above suggestions regarding the use of self -dumping scrapers 
n northern placer mining will doubtless be looked on with consid- 
erable skepticism. No direct application of the method has, so fai- 
ls known, been made in Alaska. The form of plant outlined is inex- 
pensive as compared with many already installed in Alaska, having a 
capacity not exceeding 700 cubic yards. The sum of $10,000 should 
>e ample to install an entire scraper and washing plant in Seward 
Peninsula. Even should some form of steam scraping be found appli- 
Drawback C3b[e_ _J4^ ^.- ; ; "■»' 
jX^&toSs**/ 
Bottomless steam scraper. 
3able to the wider shallow deposits, the installation of elaborate cable- 
ways, traveling towers, and the like, is not advisable, as in most cases 
their cost would be prohibitory. 
SELF-DUMPING CARRIERS. 
The conditions in the Klondike district appear to have necessitated 
^he adoption of this expensive method of placer mining. Outside the 
Klondike held the method was not seen except at one place on Masto- 
lon Creek, in the Birch Creek district. The method is adopted to 
vork rich gravels where conditions do not permit working by ordinary 
hallow open-cut methods, and where drifting is impossible or 
nadvisable. 
In considering the economic success of this method, a study of the 
ost sheet given in this report (table 1, p. 38), is most instructive. In 
he first place the average depth from eight Klondike operations con- 
dered, namely 17.5 feet, is greater than that economically advisable 
Bull. 263—05 5 
