102 



LIEUTENANT MICHLER's REPORT. 



its junction with the Gila, and extending a short distance, unites with a larger mass of the same 

 formation. A mile further south is another isolated hill, about 250 feet high, called Sierra 

 Prieta, with its base imbedded in the white sands of the desert. These hills were once one and 



the same ; 



(their 



27 



being still traceable,) and both uniting on the west. By some freak in the laws of nature, an 

 eruption in the bowels of the earth caused an upheaving of this whole section of country, and 

 changed the beds of these rivers : the one now runs due south, and the other due north, before 

 uniting. Their currents act on the same line and are diametrically opposed, and as the waters 

 meet, neither willing to yield, they open a passage through the highest part of the hill, turning 

 at right angles to their original courses and flowing towards the west. The cleft thus made is 

 about 240 feet in width. The Colorado furnishes more than two-thirds of the water. At an 

 average stage at the junction, the quantity discharged per second was found, from a mean of 

 several experiments, to be 6,249 cubic feet, and the velocity three feet per second. At the 

 same point the depth of the channel is about eighteen feet. It then widens, and becomes more 

 shallow. By daily observations with the barometer, the level of the rivers at their confluence 



it above that of the sea at San Diego. The Colorado, as its name signifies, 

 is of a reddish color, and carries down immense quantities of sand and mud. The water is sweet, 

 and excellent for drinking, but does not bear keeping long, as it soon putrifies. The Gila is 

 clearer, and its temperature warmer, but somewhat brackish in its taste, owing to the large 

 quantity of earthy salts held in solution. 



For twenty miles above the post the Colorado spreads out into a wide and low sheet of 

 water ; but above that point, to the entrance of the Great Carion, it becomes more narrow and 

 deep. An expedition under Major Heintzelman ascended this river in boats in September, 1852. 

 Another is contemplated, when it is the purpose to carry a steamboat up as far as possible, pro- 

 vided the government will render some assistance by an appropriation sufficiently large to 

 msure the safety of the boat. The belief is entertained and strongly advocated, that the Colorado 

 will be the means of supplying the Mormon territory, instead of the great extent of land 

 transportation now used for that purpose. Its head-waters approach the large settlements in 

 Utah, and^may^one^ day become the means of bearing away the produce and stock of these 



"^^®*' ^^i'^ *^^i» i^ea prominent in the minds of speculators, a city on 

 paper, bearing the name of -' Colorado City," has already been surveyed, the streets and blocks 

 marked out, and many of them sold. It is situated on the left bank, opposite Fort 



From the description given me of the Great Canon, it must resemble in appearance and 

 character those along the Rio Bravo del Norte, upon which I have already reported 



The Colorado is said to have but few tributaries ; the Gila has several, emptying in above 

 and below the Pimos villages. The annual rise in both rivers usually takes place in the 

 months of May and June, sometimes as late as July, and is caused by the melting of the 

 snows in the mountains near their head-waters ; the freshets are not of long duration. Frequently 

 the one stream will be up and the other down. The Gila becomes so low that a sand-bar forms 

 at Its mouth during the summer, and at no time does it supply much water. The Colorado, on 

 the contrary 18 navigable for small steamers, drawing two and two and a half feet water, as high 

 up as h ort Yuma. Sailing-vessels take stores from the Pacific through the Gulf of California, 



^ 



Yuma 



mouth 



and there discharge their cargoes upoa the river steamers ; the latter then transport them 



ninety miles to the uinpfinn ^tv.^ t,^^.^.,* „^„i^- ^ • . _ ^ 



ninety miles to the junction 



contract price per ton bein 



