Sec. 9. There is another result of nearly equal importance as far as regards the habitableness of the hills. When stones are thrown together in rounded or massy blocks, like a heap of hazel nuts, small force will sometimes disturb their balance; and when once set in motion, a square-built and heavy fragment will thunder down even a slightly sloping declivity, with an impetus as unlikely to be arrested as fatal in its increase. But when stones lie flatly, as dead leaves lie, it is not easy to tilt any one of them upon its edge, so as to set it in motion; and when once moved, it will nearly always slide, not roll, and be stopped by the first obstacle it encounters, catching against it by the edge, or striking into the turf where first it falls, like a hatchet. Were it not for the merciful ordinance that the slaty crystallines should break into thin and flattish fragments, the frequent falls of stones from the hill sides would render many spots among the greater mountain chains utterly uninhabitable, which are now comparatively secure. 4. Tendency to form the loveliest scenery. Sec. 10. Of the picturesque aspects which this mode of cleavage produces in the mountains, and in the stones of the foreground, we shall have to speak presently; with regard to the uses of the materials it is only necessary to note farther that these slaty rocks are of course, by their wilful way of breaking, rendered unfit for sculpture, and for nearly all purposes of art; the properties which render them convenient for the peasant in building his cottage, making them unavailable for the architecture of more elaborate edifices. One very great advantage is thus secured for the scenery they compose, namely, that it is rarely broken by quarries. A single quarry will often spoil a whole Alpine landscape; the effect of the lovely bay of the Lago Maggiore, for instance, in which lie the Borromean Islands, is, in great part, destroyed by the scar caused by a quarry of pink granite on its western shore; and the valley of Chamouni itself has lost some of its loveliest rock scenery in consequence of the unfortunate discovery that the boulders which had fallen from its higher pinnacles, and were lying in massy heaps among its pines, were available for stone lintels and door-posts in the building of its new inns. But the slaty crystallines, though sometimes containing valuable mines, are hardly ever quarried for stone; and the scenes they compose retain, in general, little disturbed by man, their aspect of melancholy power, or simple and noble peace. The color of their own mass, when freshly broken, is nearly the same as that of the compact crystallines; but it is far more varied by veins and zones of included minerals, and contains usually more iron, which gives a rich brown or golden color to their exposed sides, so that the coloring of these rocks is the most glowing to be found in the mountain world. They form also soil for vegetation more quickly, and of a more