Proceedings of the Royal Geographical Society. Vol. 13, no. 3.

Date:
1869
Catalogue details

Licence: Public Domain Mark

Credit: Proceedings of the Royal Geographical Society. Vol. 13, no. 3. Source: Wellcome Collection.

    11/128 (page 141)
    White traversed this gorge on a raft of cotton-wood. Canons are formed entirely by the action of river-water. They cannot exist except where there are the following conditions: a dry climate, never-failing streams, and a slope great enough to give force to the current of water. In the case of the canons of the Colorado Basin the surface-strata are soft, but the erosion, once begun, is carried on even through the hardest granite. Where canons exist the table- lands above them must be barren. All the water flows away in the deep river-valleys, and tributary streams come to the chief river through tributary canons. Central Arizona here and there has heights of volcanic origin. It is a fertile and beautiful country, abounding in pine, cotton-wood, grass, &c., rich in mineral wealth, and possessing a considerable rainfall. This last circumstance results from the fact that the Rocky Mountains proper terminate about tlie 35th parallel, and that the Sierra Madre of Mexico does not commence till some distance to the south-west, thus allowing the rain-laden winds from the Gulf of Mexico to penetrate to this part of the basin. Dr. Bell traversed the canon of the Aravaypa, a small tributary of the Colorado. The gorge has a length of 30 miles, but took six days and five nights for its passage. The travellers had to make their journey chiefly 'in the bed of the stream. At the entrance of the gorge was “Look-out” Mountain. The fall of the stream at first was about 50 feet in a mile ; and the rocks on either side were first conglomerate, and then sandstone overlying granite. The vege- tation was very dense, a perfect thicket of trees, through which progress could only be made at the rate of 2^ to 3 miles a day. Quails, kingfishers, wild turkeys, &c., were found in abundance. After 7i miles the canon narrows to the mere bed of the stream, and beyond this contracted part was found an open space, in which grew ash, willow, walnut, and other trees, and there was mistletoe in abundance. Farther on a change in the rocks took place, and vol- canic rocks were seen. The great cactus ( Cereus rjiganteus) was found in abundance, some of the plants rising to a height of 40 feet. Then came a second narrow gorge, and after that the sides of the canon presented the appearance of rising in different stories. The ledges of rock represented slips of the sides of the canon. The appearance of the camp at night was described as most picturesque. The sky seemed but a long narrow strip, brilliant with stars; the camp-fires blazed brightly, and the sounds of the camp-life were echoed from the sides of the canon with great vividness. The canons have proved very complete barriers against migrations from the south, and the Indians, particularly tho Apaches, have set themselves to oppose m 2