Germany is short on natural phosphates as she is long on natural potash.  But she has made up for it by utilizing a by-product of her steelworks.  When phosphorus occurs in iron ore, even in minute amounts, it makes the steel brittle.  Much of the iron ores of Alsace-Lorraine were formerly considered unworkable because of this impurity, but shortly after Germany took these provinces from France in 1871 a method was discovered by two British metallurgists, Thomas and Gilchrist, by which the phosphorus is removed from the iron in the process of converting it into steel.  This consists in lining the crucible or converter with lime and magnesia, which takes up the phosphorus from the melted iron.  This slag lining, now rich in phosphates, can be taken out and ground up for fertilizer.  So the phosphorus which used to be a detriment is now an additional source of profit and this British invention has enabled Germany to make use of the territory she stole from France to outstrip England in the steel business.  In 1910 Germany produced 2,000,000 tons of Thomas slag while only 160,000 tons were produced in the United Kingdom.  The open hearth process now chiefly used in the United States gives an acid instead of a basic phosphate slag, not suitable as a fertilizer.  The iron ore of America, with the exception of some of the southern ores, carries so small a percentage of phosphorus as to make a basic process inadvisable.

Recently the Germans have been experimenting with a combined fertilizer, Schroeder’s potassium phosphate, which is said to be as good as Thomas slag for phosphates and as good as Stassfurt salts for potash.  The American Cyanamid Company is just putting out a similar product, “Ammo-Phos,” in which the ammonia can be varied from thirteen to twenty per cent. and the phosphoric acid from twenty to forty-seven per cent. so as to give the proportions desired for any crop.  We have then the possibility of getting the three essential plant foods altogether in one compound with the elimination of most of the extraneous elements such as lime and magnesia, chlorids and sulfates.

For the last three hundred years the American people have been living on the unearned increment of the unoccupied land.  But now that all our land has been staked out in homesteads and we cannot turn to new soil when we have used up the old, we must learn, as the older races have learned, how to keep up the supply of plant food.  Only in this way can our population increase and prosper.  As we have seen, the phosphate question need not bother us and we can see our way clear toward solving the nitrate question.  We gave the Government $20,000,000 to experiment on the production of nitrates from the air and the results will serve for fields as well as firearms.  But the question of an independent supply of cheap potash is still unsolved.

IV

COAL-TAR COLORS