peale] ITINERARY. 519 



The valley of Salt Biver is admirably adapted for grazing purposes? 

 being covered with, an abundant growth of bunch-grass. The surface of 

 the valley is covered with drift derived from the mountains, and this drift 

 appears to be made up largely of coarse pebbles, which would perhaps 

 interfere somewhat with the use of the land for agricultural purposes. 

 On the river bottom, however, the land is of an excellent quality. We 

 traveled southward iu the valley, making stations on the peaks of the 

 range. We forded Salt Biver above the mouth of Crow Creek, and 

 crossing once more the Lander road, followed an Indian trail up the 

 creek. The hills west of Salt Biver are high and broken, with a ten- 

 dency to form parallel ridges, between which there are broad valleys. 

 Alter working the country between Crow Creek and Beaver Creek, we 

 turned northward through one of the broad valleys just referred to, fol- 

 lowing down the south fork of Smoking Creek, which joins the main 

 stream near the old Salt- Works, which are now deserted. Here again we 

 came upon the Lander road. We now followed it over into the valley 

 of John Gray's Lake. After making stations in the isolated hills south of 

 this marshy lake, we once more abandoned the road and followed down the 

 Blackfoot. The course of the Blackfoot is very winding through a basalt- 

 covered plain. Bordering it are numerous craters and volcanic buttes, 

 and frequently the stream cuts canons in the basaltic layer, and from 

 these often emerges into broad meadows and marshy areas. The river 

 describes a semicircle, and Lander's road, which we left at the head of 

 the stream, follows what might be called the diameter of this semicircle, 

 so that by following the river we once more reached the road, this time 

 at the ford of the Blackfoot. Near here we noticed large droves of 

 cattle, which were being driven eastward. The valley of the Blackfoot 

 formed an excellent resting-place, well suited, as it is, for grazing pur- 

 poses. From the ford we traveled eastward on the road to the head of 

 Boss's Fork. 



After making a station on Mount Butnam, we crossed back again to 

 the head of the Bortneuf and skirted the east side of the hills south of 

 Butnam until we reached the point where the river leaves the Upper 

 Bortneuf Valley. From this point the Bortneuf was followed to the 

 Snake Biver Blain. Basalt was found extending through the upper 

 canon and in the lower valley almost to the plain. Above the lower 

 canon the basalt forms a table between the Bortneuf and Marsh Creek. 



FORT HALL TO FRANKLIN. 



We reached Fort Hall on the 6th of August, thus completing our sec- 

 ond trip. A few days were spent in refitting the outfit. Every facility 

 was afforded us by Captain Bainbridge and Lieutenant Hall. Having 

 taken up our supplies that were awaiting us, we started on our third 

 trip, which was to end at Franklin, in Idaho, where our next supply depot 

 was located. 



From Fort Hall we proceeded southward up Lincoln Valley and across 

 to the Upper Bortneuf Valley, crossing the route taken before going to 

 Fort Hall. The mass of hills south of the Bortneuf Canon were next 

 examined, and we then turned eastward to Soda Springs. At the latter 

 place several days were spent in the examination of the interesting group 

 of springs located there, and in the determination of the geology and to- 

 pography of the surrounding country. 



The bend of Bear Biver at Soda Springs is one of the most remarkable 

 features in the whole district. The divide between Bear Biver and the 

 Upper Bortneuf is a basalt plain, which seems to have had its source 



