61
The internal combustion engine revolutionized
transportation and power production on the roads and on
the farm. Automobiles changed from 2-1/2 horsepower, 5
mile-per-hour, horseless carriages of the 1890s to
multi-cylinder vehicles of increasing size and power.
The industry grew by leaps and hounds. Automobile sales
increased from only 4,192 in lpOO to 181,000 in 1910 and
to 1,905,000 in 1920. By I929t when automobile sales
reached 4,455178 units, the industry was consuming
18.7 percent of all rolled steel mill products, which
at the time amounted to over 47 million tons. For the
same year, other consumer durables and containers each
accounted for 4.9 percent of steel output so that
these three categories taken together accounted for
17
about one-fourth of all steel production.
After 1929 both the absolute and relative
amounts of steel products going to the railroad industry
continued to fall, from 9.8 million tons and 20.8
percent in 1929 to only 3 million tons and 4.2 percent
in i960. In the meantime, steel destined for use in
the production of machinery and industrial equipment
showed the largest relative increase among steel consuming
groups, increasing by i960 to almost four times what it
had been in 1929. The second largest relative increase
17
Landsberg, Resources in America's Future,
p. 869, Table A16-3.