Page:Popular Science Monthly Volume 42.djvu/500

 482 some day in finding a way of regulating the seasons; some Americans already profess to be able to produce rain at will by means of dynamite. But their hypotheses, resuscitated from the notions of the Romans concerning the influence of great battles on the atmosphere, do not seem to have as yet been confirmed by experiment. But, on the other hand, the innovations that were criticised so sharply by the English humorist are in our days becoming the bases of field labors.

Scientific agriculture is gradually becoming more fully substituted for the agriculture of tradition, and it is adding in an unanticipated degree to the wealth of nations.

To the progress of this art, which is more manifest every day, our society has never ceased to lend the most active aid, both through the individual labors of its members and by prizes and incentives offered by it to inventors. It has zealously given its assistance to all the great innovations foreseen in the last century by some advanced minds, which the literary critics of the time turned into derision, but which have been especially developed during the past fifty years.

The advance of material science has, in fact, served as the basis of this surprising metamorphosis of agricultural practices which we witness and admire; and the mental and moral advance of the human mind has likewise transformed under our very eyes the education of the peasant, now raised to the dignity of a citizen. Every day he is gaining a closer acquaintance with science; he is learning to take advantage of its teachings for the increase of his production and for the amelioration of the conditions of his formerly so miserable existence. Three sciences in particular have contributed to this evolution of agriculture—mechanics, chemistry, and physiology. The endlessly various agricultural machines permit us to sow, till, and harvest over large surfaces, and with a small expenditure of human manipulation. The productive force of Nature has thereby been wonderfully increased.

But the machines of themselves create nothing; they are only applied to products already elaborated under the operation of natural forces. The processes which preside at this elaboration, the manner in which the plants are fed at the expense of the air, water, and soil, to serve afterward as food for animals, have long been mysteries. It has hardly been a century since they began to be revealed to us by chemistry, which they could not have been earlier, so long as we were not acquainted with the real chemical elements common to plants and animals, and had not discovered the secret of their passage through living organisms. Chemistry exposed this secret when it disclosed the existence of the elements themselves; it has taught us to recognize them and to measure their proportions in plants and animals; it has established, first,