210 GEOLOGICAL SURVEY OF THE TERRITORIES. 



CHAPTER I. 



GENERAL REVIEW. 

 GEOGEAPHICAL PEATURES. 



The geographical features of a country are so intimately connected 

 with its agriculturai resources, that an inquiry into the latter necessarily 

 involves an examination of the former. The size and character of its 

 mountains and valleys, extent of its i)lains, and size and number of its 

 rivers and lakes, are all items which mast be considered if we would 

 make our investigations complete. So far as I have noticed these in 

 describing the separate sections, I will not repeat them further than to 

 generalize these more minute descriptions. And it is proper for me to 

 state here that I shall confine this review almost wholly to those Terri- 

 tories and regions visited in person ; not that each locality alkided to 

 has been examined personally, but that I have visited the section and 

 learned from personal observation its leading external features. 



The boundaries of the political divisions, and even the outlines of the 

 more important natural areas, can so easily be determined from the maps, 

 that I shall omit allusion to them, except where I may have occasion to 

 do so for the purpose of explanation. 



MOUNTAINS. 



Passing over the broad plains which spread out westward from the 

 jVIissouri Kiver, the first objects to attract our attention are the mount- 

 ains. We enter upon our western journey with a desire to see them, 

 and the long monotonous ride across this broad expanse, even though 

 sweeping along at railroad speed, intensifies that desire. And when we 

 first catch a glimpse of some lofty peak or range, especially if it has a 

 crown of snow upon its summit, glittering in the bright sunshine of that 

 limpid atmosphere, all other objects for the time are forgotten. No matter 

 whether we are enthusiastic admireis of nature's works or not, the sim- 

 ple fact that we are gazing upon the snowy summit of the great Rocky 

 Mountain RaDge has in it a charm that, for the first time, at least, ar- 

 rests the attention even of the giddy youth and suffering invalid. This 

 first impression fixes itself so indelibly upon the mind that no matter 

 how often we may visit this region, how various our duties may be, and 

 how intensel}' we are devoted to them, yet after we have returned, often 

 as our minds revert to that section, the mountiiins will stand in the fore- 

 ground. ISTor is this strange, for they constitute the leading and promi- 

 nent geographical feature of the great \Yest. Aside from tlieir exceed- 

 ingly important geological and miueralogical characters, which Professor 

 Hayden and other geologists are presenting to the public, they also ex- 

 hibit external features which haveimportant bearings upon that depart- 

 ment which has been assigned to me for investigation, and this is more 

 especially true in this section of the country where the rain precipitation 

 is so small and irrigation so universally necessary. From these comes 

 the supply of water for irrigation; these are the great reservoirs upon 

 which the hopes of the agriculturist depend. As the heat of summer 

 approaches and the rays of the sun pour down upon his fields, he watches 

 day by day with anxious eyes the rapidly melting patches of snow that 

 lie upon the crest of the neighboring mountain; for, unless his ditches 

 are fed by one of the larger perennial streams, he knows that upon the 

 rivulets which fioAvfrom those crystal banks depend the life of his crop 



