Only when the districts of chalk and limestone were overstocked would the overflow be constrained to look elsewhere for shelter. Then some daring innovators, driven from the favoured land, would construct habitations by grubbing into the soil, and covering them with a roof of turf. The ancient Germans, according to Tacitus, lived in underground cabins, heaped over with dung to keep them warm during the long winter. With the invention of the earthenware stove, the German Bauer has been enabled to rise above the surface; but he cherishes the manure round his house, so to speak, about his feet, as affectionately as when it warmed his head. For a long time it was supposed that our British ancestors lived in pit dwellings, and whole clusters of them were recorded and mapped on the Yorkshire Wolds, and a British metropolis of them, Caer Penselcoit, was reported in Somersetshire. Habitations sunk deep in the rock, with only a roof above ground. But the spade has cracked these archæological theories like filberts, and has proved that the pits in the wolds were sunk after iron ore, or those in Somerset were burrowings for the extraction of chert. [Footnote: Atkinson, "Forty Years in a Moorland Parish." Lond. 1891, p. 161, _et seq._ Some pits are, however, not so dubious. At Hurstbourne, in Hants, pit habitations have been explored; others, in Kent and Oxfordshire, undoubtedly once dwelt in. In one of the Kentish pits 900 flakes and cores of flint were found. The Chysoyster huts in Cornwall and the "Picts houses" in Scotland were built up of stones, underground.] But the original paleolithic man did not get beyond the cavern or the rock-shelter. This latter was a retreat beneath an overhanging stratum of hard rock, screened against the weather by a curtain of skins. And why should he wish to change so long as these were available? We, from our advanced position, sitting in padded arm-chairs, before a coal fire, can see that there was room for improvement; but he could not. The rock-dwelling was commodious, dry, warm in winter and cool in summer, and it cost him no trouble to fashion it, or keep it in repair. He had not the prophetic eye to look forward to the arm-chair and the coal fire. Indeed, at all periods, down to the present day, those who desire to lead the simple life, and those who have been reared in these nature-formed dwelling-places, feel no ambition to occupy stone-built houses. In North Devon the cottages are reared of cob, kneaded clay, and thatched. A squire on his estate pulled down those he possessed and built in their place brick houses with slated roofs. The cottagers bitterly resented the change, their old mud-hovels were so much warmer. And in like manner the primeval man would not exchange his _abris_ for a structural dwelling unless constrained so to do.