If the soil on which our food is produced is itself deficient in some of these elements, our food must also lack them. If, moreover, we cannot for any reason add the missing elements to the soil, we must supply them to the human system in the shape of prepared nutritive salts. It is preferable, of course, that our food should contain all of the elements necessary for the proper nourishment of the body.

Thus we are forced to return to consideration of the soil. It is an established fact that our fields were originally formed from decayed rock, and analysis shows that this primitive rock contains the same minerals as healthy blood. But if our agriculturists are taught that stable manure and three or four other things are all that is necessary for the fertilization of their fields, where shall the other minerals essential to human metabolism come from?

What a man is, largely depends upon what he eats. Hence man is very largely a product of the fields. When the soil is denuded of any of the elements essential to plant and animal life, it must be properly fertilized. Incomplete or improper fertilization can have but one result, to-wit, it will produce sickly vegetation, and this in turn must produce unhealthy cattle, and since man is dependent upon plant and animal life for his food a sickly race of human beings is the ultimate result.

Is not barrenness of the soil responsible for disease in potatoes, for San Jose scale, Phylloxera, and other similar phenomena. The fields are manured profusely, it is true, but the very chemical elements which are not only essential to the development of wholesome plant tissue but which would also enable the plant to protect itself against parasites, are not used. Every farmer has observed, for instance, that grass grown upon cow dung in pastures is not eaten by cows, oxen or sheep. The instinct of the animals is correct.

In using the term incomplete fertilization, I mean supplying only potash, phosphoric acid and nitrogen, and possibly lime and sulphur, when the soil is denuded of several other elements. No matter how rich a field may be made in these things if it lacks other elements healthy vegetation cannot be grown in it.

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.

Indeed the instincts of both animals and human beings lead them under certain conditions right back to the rock and its lesson. Note the avidity with which hens confined in arid runs devoid of vegetation, worms, insects and small stones devour a compound of lime and ground bones and oyster shells. Observe a child whose ration is deficient in mineral elements eating egg shells, wall plaster, chalk and other earthy substances. What do these things mean? Nothing more than this: both chicken and child express a natural craving for the essential elements to build bone and form the basis for the tissue.