During the next hundred miles gravelly bars are of frequent occur- 

 rence, and at some of them the stream presents almost the appearance 

 of a rapid. In the intervals between, in both valleys and canons, are 

 stretches of good river, and although the bad places are worse, the 

 channel generally is better than it is beloAV. 



For the succeeding fifty miles the river bed is composed in a great 

 measure of coarse gravel and stones, and many swift rapids were en- 

 countered. Upon several were found not over two feet of water. In 

 this portion of the river there are a few sunken rocks, that would be 

 dangerous till their position became known. 



The "Black Caiion," which is twenty-five miles in extent, is now 

 reached, and in it the rapids are numerous and difficult. 



Above the caiion the river is wide and shallow, and assumes the 

 character of a rapid for so long a distance as to render any attempts 

 to carry boats to a higher point almost valueless, and, considering the 

 difficulty, hazard, and expense that would be incurred at the low stage 

 of water in taking steamboats through the caiion, I am of the opinion 

 that its mouth should be considered the practical head of navigation. 

 Up to this point the Colorado, notwithstanding the difficulties to be 

 encountered, may be pronounced navigable. The experiment was 

 attempted, as has been stated, at a time when the river had expe- 

 rienced an unprecedented fall. At most seasons of the year the navi- 

 gation would be much easier and better, and a boat of suitable model 

 and dimensions, and drawing, when loaded, but two feet, would be 

 able to ascend the Colorado to the mouth of the Black Canon with as 

 much regularity and certainty as the steamboats now upon the river 

 ply between the head of the Gulf and Fort Yuma. Although during 

 high water the river experiences a great rise, the whole channel is 

 not proportionally deepened. New bars commence at once to form, 

 and at all seasons shoals are liable to be encountered. An iron stern - 

 wheel steamer, one hundred feet long, of twenty-two feet beam, built 

 full, and with a perfectly flat bottom, having a large boiler and pow- 

 erful high-pressure engine, and drawing, when light, but twelve inches, 

 would be the description of boat best adapted for the service. 



Wood of excellent quality for the purpose of fuel can be obtained 

 in abundance on the bank at short intervals between the mouth of 

 the river and a point fifteen miles below the Black Canon. It is prin- 

 cipally mezquite, Avillow, and cottonwood. 



CONNEXION OF THE HEAD OF NAVIGATION WITH UTAH. 



A reconnaissance made from the foot of the Black Caiion towards 

 the nearest point on the emigrant trail to Utah showed that a wagon 

 road might be opened between the trail and the head of navigation. 

 For sixteen miles, while passing through the gravel hills and ravines 

 that cover the eastern slope of the intervening range of mountains, 

 the country is somewhat rough, and a little work would be required 

 to make a good roadway, but after reaching the summit there would 



