Page:Popular Science Monthly Volume 7.djvu/412

396 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, some of the minor water-courses, especially those near the river, and those near the centre 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 edges of the strata, and run in a general direction with the dip of the strata until they reach the long valleys between hog-backs; then down these valleys they turn, sometimes cutting through intervening ridges, until they find their way into the Green, where they are turned to the south, away from the mountain.



It will thus be seen that the relation of the direction of the streams to the dip of the rocks is very complex, and, for convenience of description, I have elsewhere classified these valleys, on the basis of these relations, in the following order:

 .—Transverse valleys, having a direction at right angles to the strike.