THE MINERAL FERTILIZERS 205 
The United States had for long the largest output of 
phosphate, with over 3% million tons in 1925; it has been 
surpassed by North Africa which in the same year yielded 
over 4,200,000 tons; the South Pacific Islands were third 
with 450,000 tons. 
Phosphatic fertilizers are of such value especially for 
cereals that anxiety has frequently been expressed as to 
the permanence of the supply. When President Rooseveldt 
aroused the United States to interest in the conservation 
of mineral resources, it was estimated that the available 
phosphates would only last twenty-five years. It was urged 
that export should be stopped so that America might not be 
drained of its indispensable phosphates for the benefit of 
the worn-out soils of Europe. Later investigations have 
shown that even if the output were trebled, America has 
enough high-grade phosphate to last for 1100 years, and 
Northern Africa has over 300,000,000 tons; so there is no 
fear of a phosphate famine. The present generation is no 
more to be blamed for using what it needs than were the 
Pheenicians for working the alluvial tin of Cornwall regardless 
of the future needs of the tinned meat trade. As minerals 
are irreplaceable, they should be used economically but also 
regardful of the commercial maxim, * If you have an asset, 
use it while you can.” The collapse of phosphate mining 
in England was due to the discovery of richer and more 
cheaply worked foreign deposits with which the English 
mines could not compete. If legislation had restricted the 
output of British phosphate to make the supply last longer, 
much of it would have been left unused, and Britain would 
have lost an addition to her capital and the profit derived 
from the manufacture of foreign phosphate.