. Annual report. 1st-12th, 1867-1878. Geology. 60 GEOLOGICAL SUEVEY OF THE TERRITORIES. that have fallen into the channel, and j)resents a picturesqne view to the traveler struggling along over the narrow trail, high up on the mountain side. But wherever the water forms an eddy, so that it is even moderately quiet, the number of fine, large trout that can be taken out within a limited period would astonish the most experienced fisherman. Above the canon the rocks return at once to their igneous character. This is readily shown by the differeuce in the appearance of the surface features. Althou
. Annual report. 1st-12th, 1867-1878. Geology. 60 GEOLOGICAL SUEVEY OF THE TERRITORIES. that have fallen into the channel, and j)resents a picturesqne view to the traveler struggling along over the narrow trail, high up on the mountain side. But wherever the water forms an eddy, so that it is even moderately quiet, the number of fine, large trout that can be taken out within a limited period would astonish the most experienced fisherman. Above the canon the rocks return at once to their igneous character. This is readily shown by the differeuce in the appearance of the surface features. Although the granitic portion is higher and more massive in its general aspect, yet the surface is rounded and much of it covered with debris that admit the growth of grass, while the volcanic rocks give a jagged ruggedness to the outliue. Outflows of dark-brown basalt, apparently of late date, mingled with huge masses of breccia, can be seen on either side of the valley to the summits of the mountains. The foot-hills on either side are certainly composed of breccia for several miles, which, decomposing, gives to the surface the appearance of the remains of an old furnace. Perhaps it would be better to compare it to a modern volcanic district. The debris has the great variety of colors peculiar to the remains of modern igneous action. The inclosed fragments are mostly angular, or slightly worn, and vary in size from minute i^articles to masses two feet in diameter, though they are mostly small. Some of the rounded hills are quite red on the sum- mits, as if covered with cinders. The nuclei of the mountains are granite, however, although the basis rocks are mostly concealed by the outflows of volcanic material. On the east side, the river cuts close to the base of the mountains, but on the west side, there is quite a broad belt, com- prising the foot-hills, which are composed of basaltic conglomerate, covered thickly with the debris of the same. There is here a small lake, 200 yards l
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