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Show JNTER-HOG-BAOK V ALJJEYS. 1!59 Usually the slope away from the side of the mountain corresponds above with the dip of the rock, and is gentle or steep, as the dip is lesser or greater. The side of the hog-back, next to the mountain, is composed of the cut edges of the strata, and varies greatly with the texture of tho rock, but usually it is steep or broken, sometimes buttressed, sometimes terraced, sometimes columned and fluted. On the south side of the Yampa Plateau, near the head of Cliff Creek Valley, there is an abrupt, oblique flexure, on the side of the great fold, by which the rocks are turned up, so as to sta.nd vertically. In the rocks at this place there are two very hard conglomerates; the intervening strata are soft sandstones and marls, and have been canied away, and the conglomerates stand as vertical walls, thirty or forty feet in thickness, fifty to three hundred feet in height, and several miles in length, and between these iR a broad avenue, or narrow valley, beset with ragged boulders of conglomerate. The drainage of these narrow valleys between tho hog-backs is not always along their lengths, but the water is sometimes carried by channel crossing them and cut.tiog through intervening ridges; hence there are numbers of transverse streams and wet weather channels running across valleys and through ridges. Now, if the great axis of the Uinta Fold was everywhere the summit of a water-shed, we should find the streams heading along that irregular line running off to the flank of the fold on either side ; but, as the fold is bisected by Green River, Home of the minor water courses, especially those near the river, and those near the center of the fold, follow the strike of the rocks directly into that stream. On the north side, some head back near the summit of the fold, and run to the north, crossing the hog-backs in a direction with the dip, and then turn, at the foot of the mountains, and run into the Green, where the waters take a general southerly direction. Others, again, head back on the hog-backs, or even beyond them, on the plains and the bad-lands to the north, and cut quite through the hog-backs and mountains in a direction against the dip of the rocks, and empty into the Green. This is especially true where the river has its easterly and westerly direction through Brown's Park. On the other side of the range, streams head high up in the mountains, and cut directly or obliquely against the upturned |