44 



beauties of primitive nature, we seem transported to the threshold of 

 some fairy land, secluded aud guarded against intrusion by the lofty 

 mountains that inclose it on every side. 



Entering the valley at this point our course turned sharply to the 

 north, and proceeded under the shadow of the Tetons over grassy 

 meadows and through scattering pines to the mouth of Buffalo Fork, 

 and thence along the eastern shore of Jackson's Lake and up to the 

 crossing of Snake River, just outside the boundaries of the park. This 

 region, some 50 miles in length, is one vast game park, with forests and 

 lakes and meadows and streams in the greatest profusion, and well sup- 

 plied with elk, deer, antelope, trout, and water fowl. Jt varies from 

 one to fifteen miles mide, expanding in places and again contracting 

 and curving in graceful irregularity around the projecting spurs and 

 isolated buttes which give a charming variety to its outline. 



The lignite beds, so largely developed along the Gros Ventre, if they 

 ever existed in the Snake River Basin, have been swept away, and the sur- 

 face over wide areas is nearly level and covered with a rich carpet of 

 grasses and flowers, over which numbers of deer and antelope were feed. 



ing. The underlying rock seems to consist of a white, friable, almost 

 chalky limestone, largely soluble in acid. An exposure twenty feet 

 thick of this material in the banks of a stream ea st of the Upper Gros 

 Ventre Butte has a peculiar tuberculated, irregularly beded appearance, 

 very suggestive of hot spring deposit, similar to that found on Gardi- 

 ners River farther north. Innumerable hot springs occur along the 

 streams above Jackson's Lake. Twenty of these, on an unnamed creek, 

 just beyond our last camp on Snake River, gave temperatures of 105° 



to 135° Fahrenheit The creek banks, iu this instance, although quite 

 high, were warm and spongy for some distance on either side and 

 covered with a singularly luxuriant growth of vegetation, but too 

 " shaky v to bear much weight. A few still feebly acting geysers and 

 the extinct and disintegrating remains of many others indicate the 

 former existence of a geyser basin in this part of the valley. The Car- 

 boniferous limestone which was seen emerging from under the Gros 

 Ventre at the canon, forms the luce of the mountain lower down the 



stream and makes its appearance in both the Lower and Upper Gros 



Ventre Buttes, out in the valley, where in the latter it is underlaid by 



on glomerate limestone and quartzitic sandstone probably of Quebec 



and Potsdam age. The same layers appear in the canons along the east- 

 era side of the Tetons, over which the Jurassic, Triassic, Cretaceous, and 

 Tertiary come successively into view as we proceed northward, until the 

 whole is* covered by the great lava beds from beyond. The Teton 

 Range has a nearly north and south trend along the western bound- 

 ary of the basin. The chief mass of the mountains is composed of 

 dark gray-looking gneiss-s and gneissio granite thrnst up through the 

 broken and eroded fragments of the overlying series. They are bur- 

 ied at the base in dark forests of spruce and pine, which thin out at 



