. Narrative of a journey to the shores of the Polar Sea, in the years 1819, 20, 21, and 22 [microform]. Scientific expeditions; Expéditions scientifiques. No. I.] GEOGNOSTICAL OBSERVATIONS. 527 passes betwixt high but even ranges of round-backed hills, between which and the water there are interposed high and steeply-rounded banks of a clayey soil, well covered with trees. The beds of the Mountain Torrents, which open into the river here, contain many fragments of a dark red sandstone, which would seem to indicate that the old red sandstone formation occurs in these mountains. The river contr
. Narrative of a journey to the shores of the Polar Sea, in the years 1819, 20, 21, and 22 [microform]. Scientific expeditions; Expéditions scientifiques. No. I.] GEOGNOSTICAL OBSERVATIONS. 527 passes betwixt high but even ranges of round-backed hills, between which and the water there are interposed high and steeply-rounded banks of a clayey soil, well covered with trees. The beds of the Mountain Torrents, which open into the river here, contain many fragments of a dark red sandstone, which would seem to indicate that the old red sandstone formation occurs in these mountains. The river contracting to the width of a hundred and twenty yards, at length forces itself through the Rocky Defile, a narrow channel which it has cut during a lapse of ages in the shelving foot of a hill. The channel is bounded by perpendicular rocky walls, varying in height from fifty to a hundred and fifty feet, above which there is imposed an immense body of fine sand. The form of the land would lead one to suppose, that the river at some distant period, pent in by the rock, formed a long narrow lake, whose superfluous waters were discharged by a magnificent cascadeâan opinion w^hich is countenanced by the figures of the sandy ridges, which rise immediately above the rapid to the height of five hundred or six hundred feet. The walls of the rapid consist of a very dark purplish-red com- pact felspar rock. It probably belongs to the old red sandstone formation, and seems to rest upon or to alternate with a rock, which seems to be a variety of the old red sandstone, and which is composed of light-reddish and greyish felspar and quartz, the former indistinctly crystallized. This latter rock is every where ex- posed in the bed of the river for ten or twelve miles below the rapid. For this space the river flows about three hundred feet below the level of a sandy plain, which is bounded to the westward at a considerable distance, by a continuation of the range of hills through which the river
Size: 1464px × 1707px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, booksubjectscientificexpeditions, bookyear1823
