“That might seem to be a good guess as to the probable relation of cause and effect,” replied Percy, “but we ought not to overlook some well known facts that have an important bearing.  It is exactly a hundred years since DeSaussure of France, first gave to the world a clear and correct and almost complete statement concerning the requirements of plants for plant food and the natural sources of supply.  Sir Humphrey Davy, Baron von Liebig, Lawes and Gilbert, and Hellriegel followed DeSaussure and completely filled the nineteenth century with accumulated scientific facts relating to soils and plant growth.

“Sir John Bennett Lawes, the founder of the Rothamsted Experiment Station, the oldest in the world, on his own private estate at Harpenden, England, began his investigations in the interest of practical agricultural science soon after coming into possession of Rothamsted in 1834.  In 1843 he associated with him in the work Doctor Joseph Henry Gilbert, and for fifty-seven years those two great men labored together gathering agricultural facts.  Sir John died in 1900, and Sir Henry the following year.

“That the people of Europe have made some use of the science thus evolved is evident from the simple fact that they are taking out of the United States every year about a million tons of our best phosphate rock for which they pay us at the point of shipment about five millions dollars; whereas, if this same phosphate were applied to our own soils that already suffer for want of phosphorus, it would make possible the production of nearly a billion dollars’ worth of corn above what these soils can ever produce without the addition of phosphorus.  And our phosphate is only a part of the phosphate imported into Europe.  They also produce rock phosphate from European mines, and great quantities of slag phosphate from their phosphatic iron ores.

“They feed their own crops and large amounts of imported food stuffs, and utilize all fertilizing materials thus provided for the improvement of their own lands.  Legume crops are grown in great abundance and are often plowed under to help the land.

“Do you wonder why the wheat yield in England is more than thirty bushels per acre while that of the United States is less than fourteen bushels?  Because England produces only fifty million bushels of wheat, while she imports two hundred million bushels of wheat, one hundred million bushels of corn, nearly a billion pounds of oil cake, and other food stuffs, from which large quantities of manure are made; and, in addition to this, England imports and uses much phosphate and other commercial plant food materials.

“Germany imports great quantities of wheat, corn, oil cake, and phosphates, and thus enriches her cultivated soil, and Germany’s principal export is two billion pounds of sugar, which contains no plant food of value, but only carbon, oxygen, and hydrogen, secured from air and water by the sugar beet.