The Mining Industry 
111 
caught. But when once any form of mineral wealth is taken from 
the rocks it can never be-replaced. It may indeed be used over and 
over, but nothing that man can do will cause a mine to furnish new 
ore when once the supply is exhausted, nor is there any known way 
of preventing the world’s present store of metals from being gradually 
worn out and lost. 
Why mining is limited to a few small regions. Mining can be 
carried on only in certain regions where minerals are stored. Coal 
must be mined where great quantities of dead trees and swampy reeds 
were buried long ago beneath thick layers of clay and sand. Gold 
can be mined only where it has been deposited in veins, or where the 
material from such veins has been carried away and laid down in 
gravel deposits. Man has no power to create new deposits or to 
transplant the old ones. 
With the other forms of primary production the case is different. 
Man can make a million bushels of wheat grow where not a wheat 
stalk grew before, as in Canada. He can raise a flock of a hundred 
million sheep where no sheep grazed before, as in South America. 
He can cause a forest to grow in a region that was only grassland, as 
in many parts of our prairies. He can carry plants from one country 
to another, and he can stock a river or lake with fish that are stran- 
gers to its waters. 
The possession of mineral deposits by a country is partly a matter 
of chance and partly a matter of political foresight. It is fortunate 
for the United States that its northern boundary was so run that it 
includes some of the richest of the world’s iron deposits; but since 
at that time no one knew the value of the minerals near the head of 
Lake Superior, credit for giving the deposits to this country must go 
to mere luck. On the other hand, it was not luck that gave Alaska 
to the United States; it was the political foresight of Secretary 
Seward. For two cents an acre he bought a vast region which up to 
1920 had yielded more than $2.50 per acre, chiefly in gold. Today 
every advanced country is eager to obtain either political or commer- 
cial control of places that furnish any sort of mineral wealth, but espe- 
cially coal and petroleum. This eagerness has been a cause of politi- 
cal troubles in Mesopotamia, Manchuria, Mexico, Spitzbergen, and 
elsewhere. 
Why it is difficult to discover where minerals are located. In 
mining we have almost no way of knowing where we may reasonably 
expect the product to be found. We know that certain conditions 
of climate and soil favor the growth of oranges and cotton or the