r in the
interests of posterity. In this group may be mentioned the compulsory
use of methods of mining, sorting, and metallurgy which tend to conserve
supplies but result in higher prices; the control of prices; the
elimination or lowering of the so-called resource or royalty value (p.
375); and the removal of restrictions on private combination or
cooperation, leading to more efficient methods, lessening of cost, and
better distribution of the product; or, what might amount to the same
thing, the acquirement by the government of the resources to be operated
on this larger scale.

The most effective conservation measures yet in effect are the ones
dictated by self-interest and instituted by private initiative.
Governmental measures are not yet in effective operation. Illustrations
of these two types of conservational effort are cited in relation to
coal on later pages.

THE INTEREST RATE AS A GUIDE IN CONSERVATION

In striking a balance between the present and the future, economists
have emphasized the importance of recognizing the interest rate as a
guiding, if not a controlling consideration. It is obviously difficult
for private capital to make investments of effort and money for the
purpose of conservation which will not be returned with interest some
time in the future. For the present, at least, this consideration
furnishes the best guide to procedure in the field of private endeavor.
So far as conservational measures, such as investment in an improved
process of concentrating low-grade ores, promise return of capital and
an adequate interest rate in the future, they are likely to be
undertaken.

It is clear that governments are not so closely bound by this economic
limitation. They can afford to carry their investments in raw materials
and processes at a lower interest rate than the private investor. Their
credit is better. Taxes do not figure so directly. They can balance
losses in one field against gains in another. As a matter of insurance
for the future of the nation, a government may feel justified in
inaugurating conservational measures for a particular resource without
hope of the interest return which would be necessary to the private
investor. In appraising the iron ores of Lorraine taken over by France
from Germany at the close of the war, the actual commercial value of
these ores, as figured by the ordinary _ad valorem_ method, was only
ninety millions of dollars. It is clear, however, that to