1870 SERIES. 



A series of views made daring the summer of 1S70, commencing at 

 Cheyenne, about August 1st, and terminating at Colorado City, Novem- 

 ber 10th, covering a great portion of the little known, but extremely 

 picturesque and interesting scenery of the Black Hills of Wyoming, the 

 North Platte and Sweetwater Rivers j South Pass, and the Mauvaises 

 Terres, about Fort Bridger; thence into the Uinta Mountains; down 

 Green Piver ; through Bridgets Pass, to Fort Sanders, and from there 

 along the foot-hill ranges to Pike's Peak, in Colorado. The very limited 

 time given for preparation, the lateness of the season and the large ex- 

 tent of territory covered, rendered the work extremely arduous. Nearly 

 all the views were Obtained while upon u side-trips," a small detach- 

 ment visiting the more interesting portions of the surrounding moun- 

 tains, or canons, while the main train pursued its way along the valleys. 



No. 47. Gamp near Cheyenne, at Fort 1>. A. Russell. The ren- 

 dezvous camp where the survey was organized and equipped 

 for field-service. 



No.*48. "Hogbacks." A very characteristic feature of the foot-hill 

 ranges of tin 1 Pocky .Mountains are the Hogback ridges, ex- 

 tending along the whole eastern face. Our view shows one 

 ■^ just north from Horse Creek, which iias been Cut at right 



!> angles by the mountain streams. It is composed of the 



triassic and carboniferous beds, with a trend north and south. 

 Between it and the granites which rise up into the main 

 range a valley has been scooped out by some erosive force, 

 from live to ten miles in width, extending from the head of 

 Crow Creek to the Chugwater. 



No. 49. Looking out uvon the Plains, from near the head of Horse 

 Creek, the shoreline and bed of an ancient lake, showing 

 the effects of the erosive force from the mountains p!ai 

 wards. 



No. aO-52. Castellaled Pocks on the Chugwater. A very conspicu- 

 ous feature which we notice in descending the valley of the 

 Chug is the high wall of lower cretaceous sandstone, which 

 stretches away toward the northeast like a huge wall; and 

 the jointage is so regular that it presents the appearance of a 

 massive mason work, gradually lading to decay. The sides 

 of these sandstone wallsare from 40 to (JO feet perpendicular, 

 sometimes overhanging, and large masses have broken off 

 and fallen to the base. Their most striking feature, however, 

 is to weather into most picturesque castellated forms. The 

 valley of the Chug is 100 miles long, and is a favorite place 

 to winter stock. 



No. 53. LABAMIE Piver and Valley, looking northeast. 



No. "U. Bad lands on Laramie K'iver. From the Chug, we cross table- 

 like plains for ten miles, and descend to the beautiful valley of 

 the Laramie. The tertiary rocks near the crossing have 

 weathered into quite remarkable architectural forms, much 

 like those of White Piver. The texture is similar also, with 



