Ruskin thus describes his impression of the Jura ranges, which he very aptly compares with a swell on the sea far away from a storm, the storm being represented by the wild sea of Alpine mountains:-- "Among the hours of his life to which the writer looks back with peculiar gratitude, as having been marked with more than ordinary fulness of joy or clearness of teaching, is one passed, now some years ago, near time of sunset, among the masses of pine forest which skirt the course of the Ain, above the village of Champagnole, in the Jura. It is a spot which has all the solemnity, with none of the savageness, of the Alps; where there is a sense of a great power beginning to be manifested in the earth, and of a deep and majestic concord in the rise of the long low lines of piny hills,--the first utterance of those mighty mountain symphonies, soon to be more loudly lifted and wildly broken along the battlements of the Alps. But their strength is as yet restrained; and the far-reaching ridges of pastoral mountain succeed each other, like the long and sighing swell which moves over quiet waters from some far-off stormy sea. "And there is a deep tenderness pervading that vast monotony. The destructive forces and the stern expression of the central ranges are alike withdrawn. No frost-ploughed, dust-encumbered paths of ancient glacier fret the soft Jura pastures; no splintered heaps of ruin break the fair ranks of her forests; no pale, defiled, or furious rivers rend their rude and changeful ways among her rocks. Patiently, eddy by eddy, the clear green streams wind along their well-known beds; and under the dark quietness of the undisturbed pines there spring up, year by year, such company of joyful flowers as I know not the like among all the blessings of the earth." Long faults, or fractures, where the strata have been first bent and then broken, and afterwards have been forced up or have slid down hundreds or even thousands of feet, are very numerous in mountain-ranges; and by suddenly bringing quite a different set of rocks to the surface, these faults cause considerable difficulty to the geologist, as he goes over the ground and endeavours to trace the positions of the different rocks.