With respect to habitations, we have already seen that he took up his abode in caves, at least where they were suitable. According to their depth and the light penetrating them, he either occupied the whole extent of them, or established himself in the outlet only. About the center of the cave some slabs of stone, selected from the hardest rock such as sandstone or slate, were bedded down in the ground, and formed the hearth for cooking his food. But in no country are such resorts sufficiently numerous to shelter a large population; besides, they, are generally at some distance from the fertile plains, where game would be most abundant. In such cases they doubtless constructed rude huts of boughs, skins, or other materials. Such an out-door settlement was the station at Solutré, France, where has been found an immense number of bones of horses, reindeers, also, though in less abundance, those of elephants, aurochs, and great lions.17 Rock Shelter at Bruniquel. Where no cave presented itself, these people made for themselves convenient sheltering places under the cover of some great overhanging rock. In various places in France such resorts have been discovered. The name of “rock shelters” has been given to such resorts. In such places, where we may suppose they built rude huts, are found rich deposits of the bones of mammals, birds, and fishes, as well implements of bone and horn. We have frequently referred to the presence of hearths, showing that they used fire. Like other rude races, it is probable that they obtained fire by the friction of one piece of wood upon another. M. Dupont found in one of the Belgium caves a piece of iron pyrites, from which, with a flint, sparks could be struck. Speculations have been indulged as to the probable condition of man before he obtained a knowledge of fire. If the acquisition of fire be regarded as one of the results of human endeavor, it must surely be classed as one of the most valuable discoveries which mankind has made. We do not believe, however, that we shall ever discover relics of races or tribes of men so low in the scale as to be ignorant of the use of fire. Even some of the flints which M. Bourgeois would refer to the Miocene Age show evidence of its action.18