Page:Popular Science Monthly Volume 83.djvu/17

Rh rock shelter facing the northwest, but the overhanging rock weathered away long ago, leaving a thick talus slope over the relic-bearing deposits (Fig. 1). Here Dr. Henri Martin found a nearly complete female skull of the Neandertal type and a portion of the skeleton. Placard (Charente), occupied in Mousterian, Solutréan, and Magdalenian times, is a great shallow dry cave, a comfortable and picturesque home for early man (Fig. 2). Equally picturesque is Mas d'Azil (Ariège), a subterranean stream bed with connecting caverns occupied by man in so-called Azilian times, that is to say at the very close of the paleolithic period (Fig. 3). Shelters were evidently produced artificially at an early date, and no doubt varied according to locality just as they do among primitive peoples of to-day. The ancestral hairy coat was not discarded all at once, and before it ceased to be functional, some exceptional mind had set a new fashion in garb. In more favored climes this might well have been nothing more than the proverbial fig leaf. In colder regions recourse would be had to skins of animals.

Much has been written concerning man and the glacial period, or perhaps more correctly the glacial epochs; for there seem to have been about four of these, all (or at least three) of which belong to the Quaternary. The phenomena of fourfold terraces in the valleys of Europe are widespread. To what extent these may be correlated with the four glacial epochs is still an open question.

At Amiens in the valley of the Somme, flint implements have been found in all four terraces. Of the oldest two terraces at a height of 75 and 55 meters, respectively, above the sea, very little remains. A typical pre-Chellean or eolithic industry has been found in the old gravel of the second terrace. The third terrace about 42 meters above the sea is made up of gravel at the bottom and two loess deposits, an old loess and a recent loess (Fig. 4). Chellean industry occurs in the gravel, Acheulian industry in the old loess, and Mousterian and Solutréan industry in the recent loess. That a considerable period elapsed between the deposition of these two loess deposits is proved by the presence of the so-called limon rouge at the top of the old loess, representing an old land surface, just as the brick earth at the top of the recent loess represents a decalcified land surface—the present one. The fourth terrace, the one last to be formed, is only 20 to 28 meters above the sea, the 8 meters representing the thickness of the terrace (Fig. 5). Beginning at the bottom, it is composed of coarse gravel with Chellean industry; a whitish layer of sand and gravel containing an ancient Mousterian industry associated with a warm fauna (Elephas antiquus, Rhinoceros merckii, Hippopotamus): a sterile layer of fine gravels; and lastly a thick deposit of recent loess with two horizons of later Mousterian industry.