ENDLicH.] GEEEN EIVER GEOUP. 85 



observation made throughout the entire group. For tke upper laminated 

 shales we may claim of this total thickness 1,000 to 1,200 feet, an esti- 

 mate which is subject to some local variations. 



Above the shales follows a series of sandstone beds, th e existence of which 

 can be recognized from a long distance by the i)eculiar shape which the 

 hills and mountains they compose exhibit. We first met with it on White 

 Kiver, about four miles below the junction of Evacuvation Creek. In 

 color it differs very decidedly from the underlying beds, being yellow 

 and brown with thin interstrata of dark shales. At the locality where 

 we first reached it, it forms the caiion of White River. High walls en- 

 close on either side the narrow valley through which the river winds its 

 way. Erosion attacks the sandstones very rapidly, and j)roduces some 

 of the most singularly picturesque forms. Vertical cleavages, running 

 through the sandstones, aid the destructive power of water and help to 

 form the vertical walls and bluffs that enclose the valley on either side. 



This latter is densely covered with a thick growth of willows and other 

 brush. Marchingthrough the valley is greatly impeded thereby. Added 

 to the difficulties ofl'ered by the density of the brush is the circumstance 

 that avalanchial drift along the bases of the canon walls forms almost 

 impassable barriers. The canon continues, locally widening a little at 

 some places, for about twenty-five miles down the river, to the entrance 

 of Two Water Creek, where it opens a I.ttle more. ]3ut one creek of 

 any size. Asphalt Wash, dry at the time of our visit, enters the river 

 from the south. On either side of the caiion, the walls of which are 

 1,000 to 1,200 feet in height, the sandstones have been productive of 

 many fantastic groups, due to erosion and general weathering. Thanks to 

 the vertical cleavages they show, large portions have often been carried 

 away, leaving, perhaps, but a single monument on the summit of a low 

 hill or the brow of a narrow ridge. These out-posts, the forerunners of 

 extensive areas, have a height varying from 50 to 300 feet, and have 

 assumed shapes that a lively imagination can often compare with well- 

 known models of antique statuary. The most frequent form exhibited, 

 perhaps, is one closely imitating ruins of some ancient building or city. 

 Seen by the slanting rays of a setting sun the hills seem fortified each 

 by a castle of enormous dimensions that throws a long-drawn shadow 

 to the eastward. Turrets and battlements are supplied by the skilful 

 hand of nature, that teach by their form the source whence human in- 

 genuity copied them. Cathedrals and spires rise for several hundreds 

 of feet above their gently sloping surroundings, monuments erected to 

 the enormous mass of strata that have fallen beneath the active work 

 of time. Many isolated groups the traveller cannot avoid comparing 

 with domestic scenes, so natural is the pose and distribution of their 

 members. One in particular, Avithin the White Eiver Valley, near 

 Asphalt Wash, showed so affectionate a family picture, that we named 

 it the "Happy Family." It is illustrated by the annexed cut and repre- 

 sented by three isolated columns of sandstone, the largest of which is 

 80 feet high. It is left to the imagination of the reader to discover the 

 sentiment that prompted a party of explorers to bestow so unscientific a 

 name upon a group belonging to the Upper Green River series. 



At Two Water Creek we have arrived nearly at the western border of 

 our district. We traveled up the valley of this stream leaving, for 

 some time, the White. On this river, above the junction of Two- Water, 

 we first found indications of asphalt. CJpon examination it was discov- 

 ered that this mineral occurred in vertical or approximately vertical 

 veins in the yellow sandstones and shales of the Upper Green River 

 beds. The veins vary in width from a quarter of au inch to several 



