. Edinburgh New Philosophical Journal. . Erratics of the A lps. 297 declivity i, consisting of ice, was nearly vertical, as in the annexed section ; while the part between d and b (Fig. 9) on the north side was entire- ly covered with blocks, and inclined probably at an angle of 30° or 35°. Owing to the mobility of the blocks affording very insecure footing, we ascended by the side of the fixed rock and partly upon it, and walked about a mile along the surface in the direction d e. Its appearance was new and strange, quite unlike anything I had previously seen on glaciers. No ice was visible
. Edinburgh New Philosophical Journal. . Erratics of the A lps. 297 declivity i, consisting of ice, was nearly vertical, as in the annexed section ; while the part between d and b (Fig. 9) on the north side was entire- ly covered with blocks, and inclined probably at an angle of 30° or 35°. Owing to the mobility of the blocks affording very insecure footing, we ascended by the side of the fixed rock and partly upon it, and walked about a mile along the surface in the direction d e. Its appearance was new and strange, quite unlike anything I had previously seen on glaciers. No ice was visible, no groups of picturesque cones like spires, none of the huge transverse rents called crevasses; from side to side the surface was a sheet of frag- ments great and smallâresembling a dry river channel covered with stones, and confined by walls of rock above 1000 feet in height. Yet the coating of stones, though massive in appearance, was really thin; for, on shoving aside two or three of the smaller fragments, the ice generally came into view, and no doubt constituted the entire mass from e to /. The debris spread over the surface in this way, forming what Charpentier terms the " superficial moraine," are all carried ultimately, by the slow progressive movement of the glacier, to its lower end, where they drop over the declivity, and, resting at its foot, are called the " terminal moraine" (6). The fusion at the lower end prevents this progressive motion from adding to the glacier's length. I 1 Lit" ' *t"'â â ". .'â The glacier, by means of the mud, sand, and gravel which lie below it, or adhere to its under part, polishes, scratches, and grooves the rock in contact with its sides and bottom. The scratches and grooves correspond with the line of the glacier's motionâthat is, they are horizontal, or nearly so, even upon vertical surfaces, and their aspect, form, and direction, with the polishing which accom- panies them, are- so pecul
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