36 GEOLOGICAL SURVEY OF THE TERRITORIES. 



west from the Potsdam sandstones inclusive to the top of the lignite 

 tertiaries. The trend of the Wind River range is northwest and south- 

 east. The portion in which the South Pass is located is about ten 

 miles wide, and is composed mostly of metamorphic slates in a nearly 

 or quite vertical position. It is in these slates that the gold mines are 

 found. The gulch diggings are quite extensive, and although much has 

 been done in that way, yet there is a most extended field open yet for 

 the enterprising miner or laborer. 



The facilities for placer mining are very great on account of the 

 supply of water. The gold-bearing rocks are composed of thin gneissic 

 slates, which occupy a somewhat restricted area about ten miles 

 wide and twenty to thirty miles long. Some of the slates are very thin 

 and might be made useful for building purposes ; others are more silicious 

 and fracture into columnar masses. Veins of white quartz run through 

 these slates very frequently, and it is in these the gold is found. The 

 most celebrated lodes in this district are the Cariso and " The Miner's 

 Delight." The Cariso lode is about four feet wide ; the shaft has been 

 sunk one hundred and forty feet ; the quartz yields $50 to $75 per ton. 

 About $75,000 has been taken out of the mine by its owners. The lode 

 has a strike northeast and southwest, and a dip of 70°. It was dis- 

 covered in 1867, and has been worked two years. The lode itself is 

 uiostty composed of white quartz with some iron pyrites, while the 

 country rock consists of gneiss. It will be seen at once that the great 

 value of these ores lies in the ease with which the gold can be extracted. 

 I shall describe these mines more in detail in a subsequent portion of 

 this report, and simply allude to them now in their geological relations. 



The elevations, as taken by Mr. J. W. Beaman, are of some interest. 

 At u St. Mary's Station," on the Sweetwater, 6,590 feet. Ascending 

 from ridge to ridge for ten or fifteen miles, 6,894, 7,149, 7,356, 7,405, 

 and 7,524 feet, a gradual ascent, and probably approximately correct. 

 At Fort Stainbaugh the elevation is 7,7 L4 feet; Atlantic City, 7,666 feet; 

 South Pass City, 7,857. At Washakie's Camp, at the base, main range 

 8,158 feet, and the high ridges below the central ridge, 10,215 feet. 

 This central portion of the South Pass district, or the area occupied 

 mostly by the metamorphic slates, I have estimated at ten miles in width 

 and twenty to thirty in length. The surface is somewhat rolling, but 

 cannot be called rugged, and bears evidence of remarkable ero- 

 sion. In many places long lines or rounded elevations extend across 

 the surface like the ripples of a lake. The surface has been so worn 

 down by erosion, and the irregularities filled with a heavy drift deposit, 

 that these ridges or outcropping edges just project above the surface. 

 Usually the surface is well grassed over, and in the valleys of the 

 streams large quantities of hay are obtained. The timber consists 

 principally of groves of aspen here and there, which give a beautiful 

 appearance to the scenery. 



September 1. — We arrived at Fort Stambaugh, and by the kind per- 

 mission of Major Gordon, the commander of the post, pitched our camp 

 near a fine spring, three hundred yards below the fort, and about three 

 miles from Atlantic City. This post was named in memory of a gallant 

 officer, Lieutenant Stambaugh, who was killed by Indians not far from 

 this place during the past year. It is finely located in one of the most 

 romantic spots in this region, surrounded by high hills, with beautiful 

 groves of aspen on their sides. Springs of pure water are abundant. 



September 3. — We left our camp at this locality, with a small pack- 

 train, for a short trip to the Wind River Mountains ; our direction was 

 northwest about ten miles,, across the metamorphic slates, until we came 



