41 



California and Sonora, are, like them, the repositories of a large 

 •amount of mineral wealth. They were examined by Dr. Newberry 

 with as great thoroughness and care as the character of the expe- 

 dition would permit, and found to be traversed by veins of such 

 magnitude and richness as to give promise of a field of extensive 

 mining operations. The metals, as far as observed, were gold and 

 mercury in small quantity, silver, copper, and lead in rich and valu- 

 able deposits, and iron in the greatest abundance. 



The close proximity of the treasures of these mountains to water 

 transportation greatly enhances their value. A copper mine that 

 promises to be highly successful is now being worked forty miles 

 above Fort Yuma. 



In the country of the upper Colorado the useful minerals found 

 were iron, coal, rock salt, and marble. From their geographical 

 position they have little pecuniary value, though their existence in 

 that region is a fact of great scientific interest. On the sides of the 

 canons were splendid exposures of the stratified rocks which compose 

 the great table lands of New Mexico, exhibiting all of the formations 

 from the base of the series to the tertiary. 



TRANSPORTATION FACILITIES OF THE COLORADO. 



An estimate has been already presented to the department of the 

 probable cost of transportation of stores to different points upon the 

 Colorado. Fort Yuma is the only military post at present supplied 

 in this way. The undertaking, while in its infancy, has been more 

 expensive than it would be were the amount of business greater and 

 the system fairly organized, but has proved in every respect superior 

 to the slow, difficult, and expensive overland transportation. The 

 increased amount of emigrant travel along the 35th and 32d parallels, 

 the overland mail routes, the military post which must soon be re- 

 quired in the Mojave valley, and the mining operations, both upon 

 the Colorado and in Arizona, will add largely to the business upon 

 the river. Many distant points miglit profit by the facilities of 

 approach it affords. Without entering into all of the details, which 

 will be ])rcsented elsewhere, it may be stated that the amount of 

 land transportation saved b}" sending supplies by this channel would 

 be, to Salt Lake 700 miles; to Fort Defiance 600 miles; and to Fort 

 Buchanan, near Tucson, 1,100 miles. A steamboat of the character 

 previously described in ascending from the mouth of the river to the 

 head of navigation would probably occupy from ten to twenty days, 

 depending upon the season of the year and the stage of the water. 

 There may be both delay and trouble in organizing a large transpor- 

 tation establishment in so new and in some respects so difticult a 

 region, but I can see no reason why the Colorado should not at some 

 day be used as the medium of communication with the greater portion 

 of New Mexico, Eastern California, and Utah. 



SUMMARY OF FIELD OPERATIONS. 



The examination of the natural history of the region explored was 

 zealouslv conducted bv Dr. Newberrv. wliose name is well known in 



