258 GEOLOGICAL SURVEY OF THE TERRITORIES. 



that will ever occupy this region. The first inquiry cannot be correctly 

 answered until we have received more data than at present in our pos- 

 session. Yet the answer is not impossible, for it may be given with suffi- 

 cient approximation for practical purposes. Let the following statistics 

 be procured, and then the solution can easily be obtained by simple cal- 

 cination. 



First, the extent of the land sufficiently level for cultivation and irri- 

 gation upon which water can be brought from the streams of this sec- 

 tion ; second, the rate of the descent of these streams and of the plains 

 across which they flow ; third, the amount of the rain-fall during that 

 portion of the year when it is needed to supply the growing crops with 

 moisture ; fourth, the volume of water that flows down from the mount- 

 ains and enters upon the plains during the same season. 



Sufficient statistics in the first, second, and third classes have already 

 been obtained to indicate the result; but, before presenting these I may 

 state,, in order to limit our investigation as much as possible, that we 

 may confine them to that part of the Plains lying west of the 99th me- 

 ridian, as east of this the precipitation of rain is generally sufficient to 

 supply the demands of agriculture, and it is more than probable that 

 any deficiency that may exist there will be compensated by the increase 

 that will probably occur when the water is more equally distributed over 

 the western part of the Plains. 



1. As to the extent of the level land. The answer may be given, in 

 general terms, that this is equal to the utmost capacity of the streams 

 that traverse this section ; nor is it worth while to give particulars to 

 prove this assertion, as a simple glance of the eye of the traveler, as he 

 passes across this broad expanse, will satisfy him of its truth. One 

 single view from a slightly-elevated point often embraces a territory 

 equal to one of the smaller States, taking in at one sweep millions of 

 acres. Eastern Colorado and Eastern Wyoming each contains as much 

 land sufficiently level for cultivation as the entire cultivated area of 

 Egypt, 



2. Is the rate of descent of the streams sufficient to carry the water 

 upon these lands ? In my description of the various sections I have 

 already answered this inquiry in part ; but as these statements have 

 principally applied to the country near the mountains, I will present 

 some statistics which are sufficient to give a general answer on this 

 point. The fall of the Arkansas from Canon City to the mouth 

 of Pawnee Fork \ which is about the 99th meridian) varies from 

 fifteen to eleven feet to the mile. This is sufficient, with a canal one 

 hundred miles in length, to send its waters over a plain one thousand 

 feet high. The average fall of the Canadian is about the same. From 

 Denver Junction to Fort Hays, near the assumed meridian, the descent 

 is nine feet to the mile ; sufficient, with a canal one hundred miles long, 

 to pour the waters of the South Platte on a plain six hundred feet high. 

 The fall of the South Platte between Denver and its junction with the 

 North Platte is about ten feet to the mile, and that of the North Platte 

 from Fort Fetterman to the same junction is a little over seven feet to 

 the mile. These figures give a favorable answer to the second inquiry, 

 showing that the descent of the streams and plains is sufficient to allow 

 even the higher table lands to be irrigated, leaving only the question of 

 a supply of water. I have not brought into this investigation the in- 

 quiry in regard to the productiveness of the soil, for I take it for granted 

 that wherever it can be irrigated it is productive. 



