San Francisco, en route for the field. The supplies and property of 

 the party, and also the materials for constructing a small iron steam- 

 boat, were sent from San Francisco to the mouth of the Colorado in 

 one of the government vessels. They arrived there on the 2d of 

 December. Under serious disadvantages the steamboat was put 

 together, and on the 31st of December the ascent of the river was 

 commenced. On the 11th of March a point was reached nearly five 

 hundred miles from the mouth, (in lat. 36° 06',) beyond which it was 

 impracticable to proceed in boats. It was intended that the examina- 

 tion of the river should be made in the season of low water, and 

 during the progress of the party the river proved to be lower than 

 had ever been known. In this worst stage the navigation was found 

 to be difficult, but is pronounced entirely practicable, for the distance 

 stated, for steamboats of suitable construction and of but two feet 

 draught. The trip from the mouth to the head of navigation will 

 requ?re from ten to twenty days, and the round trip from three to 

 six weeks. There is an abundance of wood for fuel on the river. 



From the head of navigation to the nearest point on the Spanish 

 trail, or Mormon road to Utah, the distance is forty miles; about one 

 hundred miles to the point where that road crosses the Muddy river, 

 a tributary of the Virgen; two hundred and twenty miles to the first 

 Mormon settlement in the Great Salt Lake basin, and five hundred 

 miles to the Great Salt Lake. 



The head of navigation is about seventy miles above the Mojave 

 valley. 



Examinations should be made for a better route between the head 

 of navigation and the Virgen, since, for the space of sixty miles before 

 reaching the Muddy river, no water is found on the Mormon road. 



By using the Colorado as a channel for forwarding supplies, there 

 would be "a saving in land transportation to Salt Lake of seven hun- 

 dred miles ; to Fort Defiance of six hundred miles, and to Fort 

 Buchanan of eleven hundred miles. 



The chains of mountains that cross the navigable portion of the 

 Colorado were found, like those of California and Sonora, to possess 

 great mineral wealth. Rich deposits of silver, copper, and lead were 

 observed, and a great abundance of iron: but gold and mercury only 

 in small quantities. 



After the completion of the reconnaissance of the river, explora- 

 tions were conducted by land along the 36th parallel, on the plateau 

 region through which the upper Colorado and its tributaries canon, the 

 greater part of which was entirely unknown. Extending over a space 

 of four degrees of longitude, these plateaus were found cut into im- 

 mense chasms, thousands of feet deep, forming intricate systems of 

 abvsscs many miles in width, and utterly impassable. Through these 

 chasms the streams just mentioned ran, and, wherever seen, foamed 

 and surged with the" rapidity of their descent. 



Near'the eastern border of the table lands, which extend from the 

 Colorado to the mountains of the Sierra Madre, the Moquis towns 

 are found. They were visited by the expedition, which arrived 

 at Albuquerque about the 1st of June, and was there broken up. 



