232 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1919. 
chromium, our domestic ores being of such relatively low gra.de that 
their use would involve important changes in practice. Practically 
all of our manganese, or 99 per cent, was, before the war, imported 
by our steel makers from south Russia, then from India, and finally 
from Brazil, but during the war we so greatly increased our domestic 
production as to become for the time being nearly independent. We 
w^ere most fortunate in this regard, for in modern steel making man- 
ganese has become almost as necessary as iron itself. 
Chromium is another of the most essential war minerals, although 
this is by no means monopolized in steel making. Its use has revolu- 
tionized the tanning industry, and its compounds are much used in 
dyeing, particularly in the khaki shades. We have always produced 
a little chromite here, but the world's center of production was 
Turkey and later Rhodesia and New Caledonia. Before the war we 
obtained our chromite chiefly from Rhodesia and New Caledonia. It 
now comes from Brazil. Cuba, and California, but our own deposits 
will soon be exhausted if worked at the war rate. 
Nickel is perhaps the most widely used alloy component of steel, 
its presence conferring such hardness and elasticity that nickel steel 
is used for steamship shafts, armor plate, shells, structural steel, 
and rails. The world depends for its supply upon Canada, whose 
reserves are estimated to contain 150,000,000 tons of ore, an amount 
apparently sufficient to meet the requirements for another century. 
Modern metal working, with all that it involves in the use of tools 
and the construction of machines, may be said to rest on tungsten 
because of the greatly increased efficiency of cutting tools of tung- 
sten steel, due to the fact that tungsten raises the temperature at 
which steel holds its temper. Tungsten ores are rare and widely 
scattered, the United States, Burma, Indo-China, Bolivia, and 
Portugal being the principal producers. The world's output is only 
about 25,000 tons of tungsten ores figured on the basis of 60 per cent 
of tungstic oxide. These are smelted in electric furnaces for metallic 
tungsten or alloys like ferrotungsten. Tungsten has a further and 
important, although indirect, influence upon the efficiency of produc- 
tion through its use in mazda lamps, in which the tungsten filament 
functions so efficiently as to produce far more light with the same 
expenditure of current. It is interesting to note that not only did 
Germany hoard tungsten before the war, but that the submarine 
Deutschland carried 55,000 pounds of the metal from the United 
iStates. 
The universality of the use of copper both in war and peace needs 
no comment, and the greatly increased demand for the metal, due 
to the expanding demands of the electrical industries, is manifest. 
The proportion of such use to that of iron has steadily increased from 
the ratio of 1 to 104 in the period from 1880 to 1885 to 1 to 53 in 
