Improper fertilization is another matter. It may consist in dressing a field with nothing but stable manure, or of applying crude sulphur or brimestone instead of using calcium sulphate—plus the other lacking elements. The advocate of crude sulphur certainly does not know how truly criminal his advice is. It is not to be denied that at the outset sulphur will increase the crop yield. But in the end—what? The sulphur will dissolve all of the essential minerals in the soil, and in the course of four or five years they will all be leached out and it will be so barren that not even wild grass can be grown upon it. Improper fertilization may also consist of a dressing of carbonate of lime applied at the wrong time or in excessive quantity. The effect of this course will be equally as harmful, namely, the transformation of the nitrogenous material into free nitrogen which will ascend to heaven. Without nitrogen albumen cannot be formed, and without albumen the formation of vegetable and animal tissue is impossible.
Wholesome soil may, then, be defined thus: It is such ground as contains a sufficient supply of humus and nitrogen and all of the essential mineral components of organic tissue. The problem of fertilization, therefore, consists of supplying any or all of these elements in which the soil is deficient. The aim of fertilization, as a rule, is merely to increase crop production. But this may prove to be not merely shortsighted, it may turn out to be a social crime. It is criminal, indeed, as a great many diseases are directly traceable to incomplete and improper fertilization.
Let us face the effect of attempting to fertilize our fields with nothing more than stable manure, which, it is true, supplies phosphoric acid, potash and nitrogen. We know that phosphorus forms the foundation of nerves, and too much of it provokes nerve irritation in exact ratio to the deficiency of sulphur. There should be twice as many sulphuric salts as phosphoric salts in the blood, if it is to be normal and the nerves are to be steady. Foodstuffs from fields that have been fertilized in this manner must, of course, contain a superabundance of phosphoric salts and be deficient in sulphuric salts. Is it strange, then, that the present age presents a picture of restless, irritated nervous activity and thoughtless action?
We must return to the primitive rock and humbly learn the lesson it has for us, and upon this rock we must rear our science of fertilization and nutrition. This rock consisted of granite, porphyry, gneiss and basalt, and these are still found upon the earth in immense quantities in practically the same condition they were thousands of years ago. Both Justus von Liebig and Julius Hensel, as a matter of fact, advocated that this rock should be finely pulverized and used as a compost to assist in restoring and maintaining the original fertility of the soil and thus aid the development of healthy plant and animal life.