Page:Popular Science Monthly Volume 22.djvu/104

94 add to the stores of plant-food in the surface-soil, which may be used by plants of a different habit that are not deep feeders.

The physiological peculiarities of the different botanical groups of plants must, however, be better understood before we can fully explain the influence of one crop upon another that succeeds it. That the special formula manures, so widely advertised in this country, and which are claimed to provide, in due proportion, the constituents required by a particular crop, are based on false assumptions, is abundantly shown in the Rothamsted field-experiments; but we can not now discuss the fallacy in detail.

The experiments with animals at Rothamsted must form the subject of a separate article.

 

HEN Sir Charles Lyell's "Antiquity of Man" and Mr. Darwin's two great works first set all the world thinking about the origin of our race, there was a general tendency among scientific men and the public generally to take it for granted that the earliest known men, those whose remains we find in the river-drift, were necessarily "missing links" between the human species and its supposed anthropoid progenitors. People naturally imagined that these very ancient men must have been hairy, low-browed, semi-brutal savages, half-way in development between the gorilla and the Australian or the Bushman. Striking word-pictures painted the palæolithic hunter for us as an evolving ape; and we all acquiesced in the pictures as truthful and accurate. With the progress of discovery, however, another phase of the question has come uppermost, and anthropologists have now for some time inclined with marked distinctness to the exactly opposite view. As we examined more and more closely the relics of the cave-men, for example, it became clear that their works of art were those not merely of real human beings, but of human beings considerably in advance of many existing savages. Professor Boyd Dawkins, who knows more about the cave-men than any one else in Britain at least, unhesitatingly states his opinion that they were in all important respects the equals of the modern Esquimaux, whom he indeed regards as their probable lineal representatives. Any one who has closely examined the remains recovered from the French caves can not fail largely to fall in with this view, so far at least as regards the high level of palæolithic art. In fact, it is daily becoming clear that the antiquity of man is something even deeper and more far-reaching in its implications than Lyell himself at first imagined. For while on the one hand geologists are inclining more and more to the opinion that palæolithic 