. Annual report. 1st-12th, 1867-1878. Geology. 132 GEOLOGICAL SURVEY OF THE TERRITORIES. Fig. 35- phyry of a lii^ht-violet color containing crystals of sanidine. As we pro- ceed down the river we iind that tbis rock is replaced by an argillo- tractbyte-porphyry, tbe white color of which contrasts strongly witli the other colors seen on the sides of the caiion. The unequal hardness of the dilierent rocks has allowed it to weather into curious and fan- tastic shapes, si)ires, towers, and minarets standing out on either side, adding to the picturesqueness of the scenery. There have once been many
. Annual report. 1st-12th, 1867-1878. Geology. 132 GEOLOGICAL SURVEY OF THE TERRITORIES. Fig. 35- phyry of a lii^ht-violet color containing crystals of sanidine. As we pro- ceed down the river we iind that tbis rock is replaced by an argillo- tractbyte-porphyry, tbe white color of which contrasts strongly witli the other colors seen on the sides of the caiion. The unequal hardness of the dilierent rocks has allowed it to weather into curious and fan- tastic shapes, si)ires, towers, and minarets standing out on either side, adding to the picturesqueness of the scenery. There have once been many hot springs throughout this region, and it is to them that the greater i)ortion of the coloring seen in the caiion is due, the iron deposits giving the reds and the sulphur the yellows. There still are a number of springs along the river's edge, although from the top of the caiion they cannot be distinguished. The center of attraction, however, is the lower fall, (Fig. 34). The river suddenly narrows to a width of only TOO feet and rushes over a ledge of trachyte, falling 397 feet to the bot- tom of the canon. The water at the edge of the fall is very deep and of a deep-green color. Huge bowlders thrown in are carried by the force of the current far out from the edge of tlie fall. When we approach the brink and look over into the abyss we begin to realize the littleness of man when in the presence of nature's grand masterpieces. Down, down goes the -whirling mass, battling and writhing as the water dashes against the rocks with a noise like the discharge of artillery. Here and there a resisting rock is met with and the watei rebounds, broken into myriads of drops, which throw back to us the sunlight resolved into its primitive colors. The bottom of the caQou reached, the immense mass of water seems 1 o dissolve itself into ^pi ay, and then recov- (!ing, it flows down the gorge an emerald- gieeu stream, dashed \\ ith patches of white, beating with furious ^\ aves the rocky wall
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Keywords: ., bookcentury1800, bookdecade1860, bookpublishe, booksubjectgeology
