As the cession of Lorraine in 1871 gave Germany the phosphates she needed for fertilizers so the retrocession of Alsace in 1919 gives France the potash she needed for fertilizers.  Ten years before the war a bed of potash was discovered in the Forest of Monnebruck, near Hartmannsweilerkopf, the peak for which French and Germans contested so fiercely and so long.  The layer of potassium salts is 16-1/2 feet thick and the total deposit is estimated to be 275,000,000 tons of potash.  At any rate it is a formidable rival of Stassfurt and its acquisition by France breaks the German monopoly.

When we turn to the consideration of the third plant food we feel better.  While the United States has no such monopoly of phosphates as Germany had of potash and Chile had of nitrates we have an abundance and to spare.  Whereas we formerly imported about $17,000,000 worth of potash from Germany and $20,000,000 worth of nitrates from Chile a year we exported $7,000,000 worth of phosphates.

Whoever it was who first noticed that the grass grew thicker around a buried bone he lived so long ago that we cannot do honor to his powers of observation, but ever since then—­whenever it was—­old bones have been used as a fertilizer.  But we long ago used up all the buffalo bones we could find on the prairies and our packing houses could not give us enough bone-meal to go around, so we have had to draw upon the old bone-yards of prehistoric animals.  Deposits of lime phosphate of such origin were found in South Carolina in 1870 and in Florida in 1888.  Since then the industry has developed with amazing rapidity until in 1913 the United States produced over three million tons of phosphates, nearly half of which was sent abroad.  The chief source at present is the Florida pebbles, which are dredged up from the bottoms of lakes and rivers or washed out from the banks of streams by a hydraulic jet.  The gravel is washed free from the sand and clay, screened and dried, and then is ready for shipment.  The rock deposits of Florida and South Carolina are more limited than the pebble beds and may be exhausted in twenty-five or thirty years, but Tennessee and Kentucky have a lot in reserve and behind them are Idaho, Wyoming and other western states with millions of acres of phosphate land, so in this respect we are independent.

But even here the war hit us hard.  For the calcium phosphate as it comes from the ground is not altogether available because it is not very soluble and the plants can only use what they can get in the water that they suck up from the soil.  But if the phosphate is treated with sulfuric acid it becomes more soluble and this product is sold as “superphosphate.”  The sulfuric acid is made mostly from iron pyrite and this we have been content to import, over 800,000 tons of it a year, largely from Spain, although we have an abundance at home.  Since the shortage of shipping shut off the foreign supply we are using more of our own pyrite and also our deposits of native sulfur along the Gulf coast.  But as a consequence of this sulfuric acid during the war went up from $5 to $25 a ton and acidulated phosphates rose correspondingly.