42 ALASKAN MINERAL RESOURCES IN 1904. [bull. 259. 
to a flow of 1.5 cubic feet per minute. It is to be hoped that if the 
Federal Government ever succeeds in establishing an adequate code 
of mining 1 law for its possessions a definition of the miner's inch will 
be included. 
The data in the following table have been compiled from statistics 
collected during an inspection in the summer of 1901 of the placer 
fields in Alaska, Yukon Territory, and northern British Columbia. 
Of the statements furnished by operators, only those which are con- 
sidered reliable have been used. The work attempted had no relation 
to the sampling or valuing of mining properties, and time did not 
permit, except in a few cases, the measuring of the ground. 
Owing to the varying conditions governing the cost of mining in 
the north, the Territory has been divided into three provinces. The 
South Coast province includes the Juneau, Porcupine, and Sunrise dis- 
tricts of Alaska. The Interior province includes the Atlin district of 
British Columbia, the Klondike district of Yukon Territory, and the 
Fortymile, Eagle, Birch Creek, Fairbanks, and Rampart districts of 
Alaska. The Seward Peninsula province includes the Nome, Council, 
and Solomon districts of Alaska. 
The Nizina district of the South Coast province and the Port Clar- 
ence, Fairhaven, and Kougarok districts of the Seward Peninsula, none 
of which were visited, are separately considered. 
In preparing the sheet the working costs of 118 different operations 
were first tabulated with reference to the method employed and to 
situation. A second table was then prepared, in which the working 
cost was augmented by an amount per cubic yard based on allowance 
for depreciation of plant'. In general six years was taken as the aver- 
age life of an individual property, and, except in the case of winter 
drifting operations, one hundred and twenty days as the working sea- 
son. It was then assumed that five annual payments are made to a 
depreciation fund. The fund is equivalent to the cost of plant and 
maintenance during the life of the property plus six years' simple 
interest on the investment at 5 per cent. Each annual payment was 
divided by the season's output in cubic yards, and the amount thus 
obtained added to the daily working expenses, to get the total output 
cost per yard, as far as possible. Prices paid for mining property 
are taken no account of, as they represent an unknown factor. 
In cases where expensive plants have been installed the amortization 
was separately figured for each case. 
In cases of shoveling-in and small mechanical plants, the installation 
and maintenance cost was taken at an average amount for a group of 
operations in each district. Where the operation implies an additional 
stripping of overburden, which is always separately charged, the cost 
was distributed and added to the gravel extraction cost. 
From the second table, where the costs were reduced to one figure 
for each district, a third (the accompanying one) was prepared, giving 
