powers in the feeding of other nations, and obtain
 in return a variety of manufactures. This did not
 happen because we found it more advantageous to
 devote an increasing portion of our energies to
 nonagricultural pursuits. On the one side, mech-
 anized industry was making tremendous headway in
 the United States. Our mineral resources were
 exploited energetically, if only for the reason
 that "in no other country can the mineral raw
 materials as a whole be delivered to manufacturing
 industry at lower prices." And as increasing progress
 was made in the standardization, mechanization, and
 mass production of commodities, the United States
 advanced to the front rank among manufacturing
 nations. On the other side, the agricultural map
 of the world was changing. While the decline in
 virgin lands was beginning to revise agricultural
 costs in this country, certain other regions which
 were experiencing the first flush of agricultural
 expansion--Argentina, Australia, Canada, Russia,
 and India--were offering severe competition to our
 products in foreign markets.(42)

 Between 1869 and 1900, while the share of national

income originating in agriculture declined from 22.2

percent to about 18.2 percent, the share of national

income originating in manufacturing increased from 14.6

percent to 18.6 percent. Between 1900 and 1960, the

share of agriculture declined further, to 4.3 percent,

while that of manufacturing increased to 30.5 percent.43

The rate of growth in metals producing-and metals-using


 Arthur F. Burns, Production Trends in the
United States Since 1870 (New York: National Bureau of
Economic Research, Inc., 1934), pp. 68-69, citing
F. G. Tryon and L. Mann, "Mineral Resources for Future
Populations," chap. viii, in Population Problems in the
United States and Canada, ed. by L. I. Dublin (Pollak
Foundation for Economic Research, 1926), p. 112.

 See Appendix A, Table 9. Yet never has a
people remained better fed.