PTJRINGTON.] COST OF MINING. 37 
Mr. Stephen Birch, operating in the Nizina district of Alaska, has 
courteously furnished for this report a summary of the costs of work- 
ing placer ground on Dan Creek. These figures are given separately 
(p. 39) after the table, as they imply a total charge of invested capital 
in addition to working costs against one season's operations. They 
are worth the attention of prospective placer miners. 
The cost of shoveling into sluice boxes in the remote parts of Seward 
Peninsula is at present from $3 to $5 per cubic yard. Some drifting 
operations have been carried on in the Kougarok and Fairhaven dis- 
tricts, on which figures are not at hand. 
Dredging estimates furnished by reliable interior operators place 
the cost at 80 cents per cubic yard where gravel must be thawed by 
points ahead of the dredge. In Seward Peninsula it is estimated that 
if the property is sufficiently large for a ten-year life, a dredge can be 
operated at the cost of 30 cents per cubic yard. The field for dredges 
in placer mining in Alaska is extremely limited. In Seward Peninsula 
it is not impossible that some of the wide, shallow creek deposits will 
be worked successfully by means of the steam scraper. The cost of 
an experimental operation on Ophir Creek was reported to be under 
20 cents per cubic yard. 
The costs of operating by two mechanical systems in Seward Pen- 
insula (involving the labor of men in shoveling into cars and tram- 
ming to the bottom of an incline, or into a bed-rock sluice leading to 
hydraulic elevator throat) are unfortunately not available for publi- 
cation. The derricking system, No. 7, however, both in the interior 
and in Seward Peninsula, appears to be superior in point of cost to 
either of the above mentioned methods for working the average 
Alaska open cuts. 
Frozen ground can not be attacked with success by the steam shovel. 
£ven where it digs the gravel successfully, if men follow it to clean 
bed rock by hand, the cost of operating is sometimes doubled. The 
steam shovel has, however, a field in northern placer mining. 
Regarding mechanical operations in general, the important princi- 
ple should be emphasized that the main expense is getting the mate- 
rial into the receptacle which conveys it to the sluice or washing plant. 
Tramming even for a long distance, and to a considerable elevation, 
idds a very small proportionate amount to the total cost of working, 
^he establishment of a permanent washing plant, economically situated 
s regards water supply and dump, should be considered by every 
Uaskan miner who proposes working the shallow creek deposits 
yhich characterize that country. The isolation of the washing opera- 
ions, together with the adoption of the most economical system of 
ramming possible, will go far toward attaining the ends of adequate 
Irrade and room for tailings, which are the essential features of suc- 
cessful gravel mining. 
