42 GRAVEL AND PLACER MINING IN ALASKA. [bull. 263 
Wood fires were used in thawing. On Pedro Creek 19 pit* 
3£ by 7 by 12 feet cost $1,140, and on an adjoining claim pits 3 by ( 
feet and 18 feet deep cost $6 per foot. The light timbering and mosf 
filling used in the Fairbanks mines is to prevent the muck walls f ron 
thawing and caving. 
In the Rampart district 30 pits 3 by 6 feet and 20 feet deep cosi 
from $75 to $100 each. The ground was parti 3^ thawed, but requirec 
no timbering. 
In the Nome district, on account of the entire lack of native timber 
shafts are cribbed with 1 or 2 inch planking, set close together, no sets 
being used. On the Snowflake bench claim, on Anvil Creek, the crib 
bingwas reenforcedby 2 by 4 inch posts in the corners. Five dollar] 
per foot is the average cost of 4 by 5 shafts, timbered, in unfrozen oi 
partially frozen ground. 
On Bonanza Creek, near Nome, pits in the shallow creek bed, 3 by j 
feet and 7 feet deep, are said to cost 50 cents per f oot. a The ground is 
only lightly frozen and requires no timbering. On Ophir Creek, ir 
the Council district, it costs on an average $5 to sink pits 7 feet deep 
In the northern part of Seward Peninsula the ground is solidl} 
frozen. In the Kougarok district pits 35 feet in depth, with stean 
thawing, cost $8 per foot, and require no timbering. 
In the Candle or Fairhaven district, adjacent to Kotzebue Sound, 2£ 
pits 12 to 15 feet deep cost $4 a foot. It was necessary to thaw tc 
bed rock. The equipment cost $500. 
RESULTS OF PROSPECTING. 
Numerous reports from many parts of Alaska indicate that the 
amount of gold obtained per cubic yard from prospect shafts does no 
equal that extracted b}^ subsequent actual mining. The reverse is very 
rarely true. It is difficult to assign a reason for this discrepancy othe: 
than that, owing to the frozen condition of the gravel, some of th< 
gold escapes when small lots are washed in the winter. Frozen grave 1 
does not easily disintegrate, even in hot water, and unless the residuin 
from panning or rocking is saved and re washed, losses very likelfl 
occur. 
It is needless to urge the importance of prospecting ground in i 
thorough manner before expensive machinery is installed. The man; 
failures through the long history of mining which have resulted from 
precipitate expenditure to exploit supposed valuable properties presen 
an open page of admonition to him who cares to read. 
The sampling of winter dumps as they are extracted does not appea 
to have received the attention which it deserves. A method used b; I 
Mr. Kelley, of Dominion Creek, in the Klondike, is as follows: 
The ordinary conical dump of frozen gravel, PI. Ill, B (p. 10) | 
a This work is probably done in the winter with labor at $2.50 a day and board. 
