Page:A Treatise on Geology, volume 1.djvu/149

 CHAP. VI. the green slate of Coniston. It is unsafe at present to quote the foreign localities, though perhaps the Scandinavian schists containing Oleni, like those of Malvern, North Wales, and Angers, may be of coeval date, and the lowest palæozoics of North America may be put on the same parallel.

Physical Geography.—The slate system, though but a very inferior feature along the Grampian ranges of Scotland, forms the most elevated points of land in England. Supported by granite, and mixed with igneous masses, the slaty rocks of the English lakes rise to more than 3000 feet in height (Sea fell is 3160, Skiddaw 3022), and present a variety of outline, and intricacy of combination, which, in connection with clear lakes and considerable waterfalls, leave to Switzerland little superiority, except that beauty and grandeur imparted by the mighty summits of snow, which is perfectly inconceivable to an English tourist, who might shudder by his fireside at the very mention of a wintry view of Helvellyn.

Each of the slate formations of Cumbria has its own characters of scenery: broad swelling forms accompany the Skiddaw rocks; enormous crags and fearful precipices, with broken waterfalls, characterise the middle division, and the upper has, generally, a number of serrated hills of very inferior effect in the scenery. The lakes of the Cumbrian region are often so deep as to preclude wholly the notion of their having been eroded by water. The valleys are, according to Sedgwick, usually accompanied by great dislocations, radiating from the central elevations of the rocks.

The slaty regions of North Wales are superior in the breadth and grandeur of their effects, though not in picturesque beauty, to the districts of the English lakes. Their effective height is greater, from the entrance of many arms of the sea into the midst of the mountains: there is, besides, something deeper and richer in all the colouring, a greater expanse of surface, largeness of feature, and freedom of outline, which reminds us of