56

ECONOMIC PRINCIPLES

change in the other. Regarding this feature alone, it affords
a basis for the required valuations. For illustration take the
case of the crushing of cotton-seed in relation to the two
most valuable products, cotton-seed oil and oil-cake. In
rough, general figures, a ton of seed yields about one-third
of its weight of cake and meal, and about a hundred gallons
of oil are obtained to each ton of cake and meal. Taking
these proportions, the mill-owner needs to find markets for
as many tons of cake as he produces hundreds of gallons of
sil, He must, therefore, assign such relative values to these
goods as will evoke demands ‘in the named proportion.
If, for each ton of cake, he can sell but ninety-five gallons of
oil, either the cake is valued at too low a figure, or the oil
at an excessive figure, or both. If, on the other hand, he
can sell only nineteen hundredweights of cake for every
hundred gallons of oil demanded, the oil is offered too
cheaply, or the cake priced too highly, or both. When the
prices are properly adjusted, the amounts of the two
commodities demanded will be in the proportion in which
they result from the crushing process. For the products
jointly, the relation of cost of production to value will follow
the principles already examined for single products. Having
arrived at a principle for their relative valuation, the needed
additional feature in the solution of the problem of their
separate valuations is supplied.
But a second point of view may also be considered, and
throws useful light on this class of problems. For illustration
take the case of milk production. The quality of the milk
produced may be varied a good deal by ‘suitable choice of
animals and suitable feeding. A farmer whose milk yields
a pound of butter for every twenty-four pounds of milk may
consider that he would gain by such changes as would cause
a yield of butter of one pound from every twenty-three pounds
of milk. The products, butter and skim milk, are not
yielded in invariable proportion. Under these circumstances
the cost of a given amount of the single products can be
determined in addition to their joint cost. The richer milk
can be secured at an increased cost, and the question to be
considered is whether it is worth while. If it be wholly a