bute "repairs and maintenance," either on a basis of shop
returns, or a distribution over all departments on the basis of
the labor employed in those departments, on the theory that such
repairs arise in this proportion; to distribute sampling and assaying
over the actual points to which they relate at the average cost
per sample or assay.

"General expenses," that is, superintendence, etc., are often not
included in the final departments as above, but are sometimes "spread"
in an attempt to charge a proportion of superintendence to each
particular work. As, however, such "spreading" must take place
on the basis of the relative expenditure in each department, the
result is of little value, for such a basis does not truly represent
the proportion of general superintendence, etc., devoted to each
department. If they are distributed over all departments, capital
as well as revenue, on the basis of total expenditure, they inflate
the "capital expenditure" departments against a day of reckoning when
these charges come to be distributed over working costs. Although it
may be contended that the capital departments also require supervision,
such a practice is a favorite device for showing apparently low
working costs in the revenue departments. The most courageous way
is not to distribute general expenses at all, but to charge them
separately and directly to revenue accounts and thus wholly into
working costs.

The second problem is to reduce the "suspense" or capital charges
to a final cost per ton, and this is no simple matter. Development
expenditures bear a relation to the tonnage developed and not to
that extracted in any particular period. If it is desired to preserve
any value for comparative purposes in the mining costs, such outlay
must be charged out on the basis of the tonnage developed, and such
portion of the ore as is extracted must be written off at this
rate; otherwise one month may see double the amount of development
in progress which another records, and the underground costs would
be swelled or diminished thereby in a way to ruin their comparative
value from month to month. The ore developed cannot be satisfactorily
determined at short intervals, but it can be known at least annually,
and a price may be deduced as to its cost per ton. In many mines
a figure is arrived at by estimating ore-reserves at the end of
the year, and this figure is used during the succeeding year as a
"redemption of development" a