248 GAME. 



a trout in any tributary of the North Platte Eiver, 

 while every tributary of the South Platte in the moun- 

 tains furnishes an abundance of this noble fish. 



The head waters of the Cache-le-Pondre and Laramie 

 are in many places but a few yards apart, rising on 

 different slopes of the same mountain. One set of 

 tributaries is full of trout ; the other set has not one. The 

 same peculiarity occurs in many places for example, in 

 the rim of mountains which separates the North and 

 Middle Parks, and the range separating the waters of 

 the Papo-agie and the North Platte. North, south, and 

 west it is the same : no single tributary of the thousands 

 that finally find their way to the North Platte has trout. 



From the facts that the head waters of these tribu- 

 taries are so pure, and that they rise in the same strata 

 and under precisely the same circumstances as the 

 trout streams, it was for a long time supposed that there 

 was something injurious in the main stream of the North 

 Platte preventing the trout from passing up. 



A gentleman much interested in these matters deter- 

 mined to test this. The small stream on which Fort 

 Sanders is situated is extremely pure and clear a model 

 trout stream, but containing no trout. In 1868 this 

 gentleman sent east for eggs, and went to some trouble and 

 expense in arranging a proper hatching box in the very 

 head spring of the brook. The eggs were hatched, and 

 the young trout, apparently perfectly healthy, were, when 

 large enough, turned into the brook to take care of 

 themselves. I am informed (in 1875) by an officer 

 stationed at Fort Sanders that not a single one of those 

 trout has ever been seen or heard of since. 



However pure the head waters of streams, their 

 impurity lower down has a most decided effect in keep- 

 ing trout from those heads. Thus the waters of the 

 Black Hills of Dakota are pure, cool, and delicious 

 enough to satisfy the most fastidious trout, yet there 

 is not one in all this splendid mass of mountains. Nor is 



