- along the Colorado, however, with the exception of a few places, has been almost a terra 
* 
Bec 
LETTER TO THE OFFICER IN CHARGE OF THE OFFICE OF EXPLORATIONS 
AND SURVEYS. 
Wasuineton, May 1, 1860. 
Sir: I have the honor to submit the accompanying report upon the Exploration of the River 
Colorado of the West. The presentation of this has been delayed until the maps of the region 
explored should be completed. A preliminary report was handed in shortly after the return 
of the expedition from the field; and during the explorations the department was kept apprised 
of their general progress. 
The main object of the work being to ascertain the navigability of the Colorado, detailed 
information upon that point was also forwarded as the examinations proceeded. It was my 
desire, in the communications referred to, rather to lay stress upon than to undervalue the 
difficulties encountered. At the same time the opinion was expressed that the delays and 
obstacles met with in the first experiment might be ina great measure avoided upon a new 
trial, conducted with the provisions that experience had suggested. 
This view has since received ample confirmation. The outbreak among the Mojave Indians, 
and the consequent movement of troops into their territory, caused the navigability of the 
Colorado, at different seasons of the year, to be thoroughly tested. The result has been 
beyond my most sanguine estimate. The round trip between the head of the Gulf and the 
Mojave villages—which are 425 miles from the mouth of the Colorado, and but 75 miles from 
the point which I think should be regarded as the practical head of navigation—has been made 
in eight days. 
I would again state my belief that the Colorado would be found an economical avenue for 
ihe transportation of supplies to various military posts in New Mexico and Utah. It may be 
instanced that the amount of land transportation saved by adopting this route would be: to 
the Great Salt lake, 700 miles; to Fort Defiance, 600 miles; and to Fort Buchanan, 1,100 miles. 
The estimate contained in the hydrographic report, of the cost attending the river service, is, 
I think, a liberal one. The first organization of transportation establishments, to connect the 
upper part of the river with the interior of the Territories mentioned, would be attended with 
expense and trouble; but I am convinced that it would ultimately be productive of a great 
saving in both. The results of the exploration, so far as they relate to the navigability of the 
river, will be found embodied in map No. 1 and in the hydrographic report. 
The region explored after leaving the navigable portion of the Colorado—though, in a 
scientific point of view, of the highest interest, and presenting natural features whose strange 
sublimity is perhaps unparalleled in any part of the world—is not of much value. Most of it 
is uninhabitable, and a great deal of it is impassable. A brief statement could comprise the 
whole of what might be called the practical results of the land explorations. The country 
incognita. Concerning the character and value of the portions previously explored, great differ- 
ences of opinion existed. Between the mouth and the highest point attained are many localities | 
unique and surpassingly beautiful. Some of the Indian tribes, of whom little has been known, . 
are subjects for curious speculation; and it being doubtful whether any party will ever again — 
pursue the same line of travel, I have thought it would be better, in place of condensing into 
a few lines the prominent facts noticed, to transmit the journal kept during the expedition. ee 
This involves the presentation of what may appear extraneous, and perhaps beyond the 
