68 FROM FORT LARAMIE TO FORT BIDGER. 



extent with pine, dark bands of soil were observed, having the 

 appearance of being formed bj the decomposition of carbonaceous 

 matter, which however must have been altered bj heat. It is 

 highly probable that these beds have been tilted up by some gra- 

 nite rock, although none appeared on the surface, being probably 

 covered up by the secondary beds which have been deposited since 

 the eruption took place. The valley between the hills and the 

 river gradually rose, and where the rocks had been protruded 

 must have been at a considerable elevation above the latter. They 

 were composed of white and gray sandstones, evidently fossili- 

 ferous, but the fossils were in so decomposed a state that no speci- 

 mens, with the exception of some imperfect encrinital stems, 

 could be obtained. The beds were nearly horizontal, and were ana- 

 logous to the same formation over which we had been passing all 

 along the Platte. Toward the close of our march to-day, the sum- 

 mit of one of these lower hills was found to be composed of clay 

 similar to that of the Chimney Rock, and to the formations in 

 that vicinity. The elevations, though not so marked as to pecu- 

 liarity of form, resembled them in their general features. The 

 rocks on the north side of the river are still granitic. 



Encamped, after a march of twenty-one and a-half miles, on the 

 right bank of the river, which is here growing smaller and the 

 current more gentle. In the course of the day we passed a party 

 of eight wagons from Iowa, bound to the land of gold. A number 

 of women and children were of the party, and application was 

 made for medical attendance upon one of the former, who was 

 about being confined. 



Friday^ August 3. — Ther. at sunrise, 31°. The rocky ridges 

 gradually disappeared as we followed up the valley of the Sweet- 

 water, occasionally crossing long and lofty spurs which would not 

 admit of our passing between them and the river. The soil is 

 very barren, producing only the artemisia, and two or three varie- 

 ties of grass ; a species of .Zns, which is quite abundant, the imww 

 ceruleum, a yellow Potentilla, a scarlet star-shaped flower, with 

 tubular corolla, and (Enothera hispida were seen in the bottoms. 



The character of the valley for the last two days has been ana- 

 logous to that of the Platte below Fort Laramie. The last of the 

 granite was passed yesterday. The hills on both sides of the 

 river have since been formed of sandstones and clay, the latter of 

 which forms the irregular outline of the bluffs above Ash Hol- 

 low, and in many instances presenting a similar appearance when 



