Note 7 — Chapter VII · THE MARCH OF SCIENCE

As we have seen that, apart from the sentimental reasons which have been suggested,7 animal and flesh foods must, for economical reasons, have been abandoned long before the end of the century, the grazing of cattle being far too expensive a method of utilising the soil, we may be quite sure that the sciences connected with agriculture will receive far greater attention than they now enjoy. It will grow more important with every decade to obtain the greatest possible tribute from the portions of land, steadily decreasing in area, which can be spared from the growing needs of the builder. Every discovery of the chemist which can be laid under contribution by the agriculturist will eagerly be seized upon. Every means which can be devised for replacing what we take from the soil will be utilised to the full: and of course the inevitable disappearance of the horse as a means of traction, and of the flocks and herds which now yield manure, and perhaps the gradual exhaustion of the minerals (as rock phosphates) from which artificial soil enrichers are prepared, will make it necessary to rearrange, on safe, economical and convenient lines, our present plans of sanitation. The insane wastefulness of draining into the sea cannot long be tolerated. Every conceivable means of conserving our mundane capital will have to be made use of. In other ways science will come to the rescue. The farmer’s sufferings from the depredations of vermin of various kinds will perhaps never be much affected by invention, because all nature is so curiously interdependent that the eradication of one pest has an awkward way of intensifying some greater evil: we destroy birds and are punished by a plague of caterpillars. The accidents of climate, too, can perhaps only be obviated in a very small measure, though the science of meteorology, constantly being helped by facilities for better observation-reporting, will unquestionably help the agriculturist by giving him timely warnings. It seems hardly possible to doubt that the eccentricities of climate and the unexpected shifting of the rainy season in Manchuria during the Russo-Japanese war must have been caused by the vast atmospheric disturbances created by days and weeks of cannonading: and of course it is an old theory that heavy gun-fire “brings down the rain.” Military historians say that the number of wet-day battles altogether exceeds any expectation which could have been formed without allowing for effects of this sort. When science has pondered upon the subject, and instituted in an ordered manner experiments of a kind hitherto never taken very seriously, it may very well be that some means less violent than the detonation of explosives may be discovered by the practical meteorologist for creating disturbances in the atmosphere; and while it may not be possible to prevent excessive rainfall at inconvenient times, it seems easy to conceive that when there is moisture in the atmosphere we may be able to bring it down as rain. Of course this is a very different thing from breaking up droughts: and artificial rain-making cannot in itself be anything but a momentary expedient. The effects of deforestation have for some time been observed and the plan of improving waterless areas by the contrary process is already discussed. While it seems rather a “large order” to undertake to meddle with the balance of atmospheric composition on a large scale, especially as we know so little of the conditions that even success might very possibly be attended by unforeseen and perhaps calamitous results, there is nothing intrinsically absurd in the notion that we might adopt means on a vast scale for increasing oceanic evaporation and, utilising the exact foreknowledge of winds and air currents which we shall certainly have achieved, bring moisture and rain to arid tracts or countries suffering from drought. The operation would no doubt require to be stupendous, but the next century is not going to be afraid of stupendous operations; and anticipating vast and unforeseen progress in meteorology, it would be hazardous to believe that no practical use will be made of such progress.