GEOLOGICAL SURVEY OF THE TERRITORIES. 75 



Turtle Hill River. Three of these are of considerable size, probably 35 miles long, the 

 bluffs along nearly all of them being more or less covered with scattered pine, and 

 their valleys occupied with clumps of cotton-wood, oak, ash, &c. 



From the mouth of Turtle Hill River to that of the Wazihonska there are still a 

 greater number of short soutiiern branches, all containing springs of water and abound- 

 ing in pine and beautiful oak groves. 



Wazihonska means in Dakota tongue " the place where the pine extends far out ;" 

 and this stream, whose mouth is in longitude lUO'^, is probably 40 miles long, and all it? 

 bluffs and side ravines are green with pine. Its valley, though not so wide, is very 

 similar to that of the Niobrara in this part, which has been described. 



Snake River, whose mouth is in longitude 100° 45', is quite a large stream, some 3C 

 yards wide, its bluffs covered with pine, with a narrow valley like the Wazihonska. 



Above this there is scarcely any branch coming in from the south deserving mention. 



Niobrara is a very shallow and "swift-flowing stream," as the Canadians say, L'eau 

 qui court, abounding in rapids in two-thirds of its upper course, and in its middle por- 

 tion filled with small islands. In the lower portion its width exceeds that of the Mis- 

 souri River and is spread out over sand-bars. The bed in the broad portions is quick- 

 sand and difficult to ford. Its waters rapidly increase in volume through its middle 

 portion, from the multitude ot springs and streamlets that constantly flow into it from 

 the foot of the bluff's and out of the ravines. It furnishes no navigation, except it 

 might be for light flat-boats during floods, and probably might be used for rafting. 

 Logs could be driven if the timber should be found of a quality, quantity, and acces- 

 sibility to defray the expenses. I cannot, however, look upon it as capable of furnish- 

 ing timber for the country on the Missouri, for the reason that nmch of the pine is too 

 small, crooked, and knotty, and grows in places difficult to transport it from. The 

 species is what is called the Rocky Mountain pine, has a yellowish-white appearance, 

 and abounds in resin. The distance on the Niobrara over which these i)ine ravines 

 extend is about 120 miles. 



A road could not be made on the bottom-lands of the Niobrara ; it must keep out on 

 the high prairie so as to head the ravines. From the mouth to Turtle Hill River, it 

 would take the narrow divide between the Niobrara and Ponka Rivers. It should 

 remain on the north side of Turtle Hill River from 20 to 30 miles farther, and then 

 cross that stream, as it would thus avoid the sand at the junction of the Niobrara and 

 Turtle Hill Rivers, and cross the latter where there is a better foi'd or narrower stream 

 to bridge. Turning then toward the Niobrara, the river must be crossed in longitude 

 101° 20' to avoid the sand-hills, and the route must continue on the south side to about 

 longitude 102°, when it should again cross to the north side. These crossings for a 

 wagon-road could easily be made at a ford or by bridging, but a proper bridge for a 

 railroad-crossing at these places would be a stupendous undertaking; for on account 

 of the nature of the banks and ravines good approaches could "not be found so as to 

 descend to the level of the stream, and the bridge would have to be built very high. 

 From longitude 102° west there are no difficulties beyond a scarcity of wood in reach- 

 ing Fort Laramie, or continuing direct to the South Pass, and in this course abundance 

 of excellent pine would be found near Rawhide Peak. 



A preferable road might be found by continuing up Turtle Hill River to its source, 

 and then along the divide between Niobrara and White Rivers, striking the former 

 stream in loiigitude 102° ; but these divides are generally bad for wagon-routes on ac- 

 count of scarcity of water, and it is not certain that we would by that route avoid the 

 sand-hills. 



The area occupied by tbe Niobrara is about 450 miles in length from 

 east to west, and from 40 to 60 miles in width from north to south. 



The next sub-hydrographical basin, and perhaps in many respects the 

 most important one in the Missouri Valley, is that of the Platte, which 

 flows into the Missouri Eiver near latitude 41° 3' 24". Its valley forms 

 a natural grade for a railroad to the foot of the mountains, and already 

 one has been constructed from Omaha City, 640 miles, and before this 

 report will be given to the world it will doubtless be completed to the 

 foot of the mountains. The Platte River takes its rise in the Laramie 

 range, and flows for the greater part of its course through the more recent 

 beds of the Tertiary deposits. The area drained by this river must be at 

 least 600 miles from east to west, and SO to 150 from north to south. 

 Although a wide stream, 1,000 jards or more, the water is so shallow 

 and the channel so shifting that It can never be rendered navigable even 

 for Mackinaw boats. Even the fur-traders have never been able to rely 

 upon it for the transportation of their furs and skins. 



On the left or north side of the Missouri there are comparatively few 



