Sec. 3. It, however, fell within the purpose of the Great Builder to give, in the highest peaks of mountains, examples of form more strange and majestic than any which could be attained by structures so beneficently adapted to the welfare of the human race. And the admission of other modes of elevation, more terrific and less secure, takes place exactly in proportion to the increasing presence of such conditions in the locality as shall render it on other grounds unlikely to be inhabited, or incapable of being so. Where the soil is rich and the climate soft, the hills are low and safe;[52] as the ground becomes poorer and the air keener, they rise into forms of more peril and pride; and their utmost terror is shown only where their fragments fall on trackless ice, and the thunder of their ruin can be heard but by the ibex and the eagle. Sec. 4. The safety of the lower mountains depends, as has just been observed, on their tendency to divide themselves into beds. But it will easily be understood that, together with security, such a structure involves some monotony of aspect; and that the possibility of a rent like that indicated in the last figure, extending itself without a check, so as to detach some vast portion of the mountain at once, would be a means of obtaining accidental forms of far greater awfulness. We find, accordingly, that the bedded structure is departed from in the central peaks; that they are in reality gifted with this power, or, if we choose so to regard it, affected with this weakness, of rending downwards throughout into vertical sheets; and that to this end they are usually composed of that structureless and massive rock which we have characterized by the term "compact crystalline."