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Show 58 FROM FORT LARAMIE TO FORI BRIDGBR. Booming has been about parallel with the range of the Black IJills, the base of which could - frequently be seen from the taore ele-vated portions of the road. The valley of the Platte also was to be seen far in the distance to the jiorth. Crossing La Bontl Greek, encamped near a fine spring, after a fatiguing march of twenty-four miles. In passing along the ridge, the only- rock exposed consisted of coarse sandstone, with a derided dip to the north- east of 15°, and beds of clay were interposed between the strata. On descending from the ridge into the valley of the fork, seme siliceous limestone was found, from which a few fossils were collected. In the same locality Were masses of sandstone of a reddish colour. On the side of a ravine to the left of the road, the same sandstone appeared to crop but. After crossing this stream, the geological character of the country changed materially. The soil assumed a red colour, being composed principally of red sandstones and shales. To the left rose a high crest or ridge crowned with gray and red sandstone, which was very hard. Th* general direction of this ridge was N. N. W. and S, S. E*, and it was manifestly formed by the upheaving of the strata,- the dip being at least 45° to the north- east, while the south- west fttce of the rocks was- very precipitons. At nearly the highest, point of the ridge, a small ravine occurred, containing a layer of coal shale, apparently overlaid by dark shales, and layers of ^ re^ clay and light slaty shales. The portions of these strata which were exposed were in So decomposed a state that no fossils could be obtained except very imperfect ones.' In the valley. of La Bontl Creek, the soil was found to be formed* by the decomposition of highly ferruginous rook. Before the cross*-' ing of this stream, a ravine exposed'a layer of gypsum, which- was very fine and white, and of considerable thickness. Overlying it were layers of red sandstone and shales, conformable with the apparent dip of the sandstones forming the crest. A mile or two beyond the La Bontl, the gray sandstone was seen cropping out, overlying the red sandstone, and with a considerable dip to the north. Above these were layers of red and light shales and impure, carboniferous limestone, from which, a number of fossils ( Avicula monotit, and Cardinia) - were collected. The liniestone seemed to be composed, to a great extent, of shells: in the more sandy and slaty shales the fossils were not so numerous; To the left were some eminences composed of the more resisting sand- |