54 FROM FORT LARAMIE TO FORT BRIDGER. 



stone and calcareous rocks, cemented in an argillaceous matrix. 

 The general direction of the strata was nearly horizontal, but 

 there were evident local displacements, caused apparently by 

 subterraneous upheavings. In some cases the strata were declined 

 as much as 30°, and in opposite directions, within a short space. 

 In many places large quantities occurred of the fragments of 

 primary rocks, resulting, most probably, from the decomposition 

 of conglomerate : the sandstone was often good, although generally 

 too scaly for building purposes. 



CHAPTER III. 



FROM FORT LARAMIE TO FORT BRIDGER. 



Wednesday, July 18. — Taking leave of our friends at Fort 

 Laramie, we continued our journey this morning. The next place 

 where we shall meet with a human habitation will be Fort Bridger, 

 on Black's Fork of Green River, distant about four hundred miles. 



While the train followed the travelling track, I took a road 

 nearer the river, and examined a quarry which the workmen from 

 the fort are here opening. The strata exposed in the blufis were 

 principally gray sandstone, with some thin calcareous layers, the 

 general dip being south and south-west about 17°. On the oppo- 

 site bank of the river, which is high and covered with pine, the in- 

 clination appeared to be much greater. The fossils were quite 

 imperfect. The only ones that could be descried were abundant 

 remains of encrinites. The limestone at the quarry is dark, car- 

 boniferous, with conchoidal fracture, and slightly foetid. It lies 

 in layers of six or eight inches thick, and is immediately overlaid 

 by slaty shales and gray sandstone. A considerable number of 

 Pr oductus semi-reticulatus wsiS found in it, as well as in the sand 

 between the layers : some specimens of a large sort of oyster lay in 

 a nearly horizontal position. Some imperfect fossils were also ob- 

 tained from the sandstone. The general surface is formed of 

 strata of grayish sandstone and clay, the former varying in hard- 

 ness, some being very friable, while others are exceeding hard, 

 especially some which were slightly coloured by oxide of iron. 



