REPORT OF F. M. ENDLICH, S. N. D. 



LETTEE OF TEANSMITTAL. 



Washington, D. C, May 15, 1878. 



Sir : I have the honor herewith to submit my report of 1877 as geolo- 

 gist of the Sweetwater division. The party to which this area was as- 

 signed for exploration consisted of G. B. Chittenden, topographer direct- 

 ing ; Charles H. Howes, assistant topographer ; Edward T. Clymer, as- 

 sistant geologist, and myself. Two packers and a cook completed the 

 personnelle. According to instructions received, we started from Chey- 

 enne on May 31, by rail, for Salt Wells station. On June 2 we com- 

 menced our field-work. Making Camp Stambaugh and Eawlin's Springs 

 our bases of supplies, we arranged our trips so as to reach them at the 

 proper time. To the officers of both Camp Stambaugh and Camp Brown 

 we are under great obligations for the efficient aid they kindly rendered 

 us in many instances. Our work was facilitated and we were enabled 

 to avoid many annoyances through their cheerfully extended courtesy. 



During the season two of the members of our party were taken sick 

 with mountain fever, but both recovered fully. After having com- 

 pleted my portion of the work, I left the party on September 17, rode to 

 Eawlings' and proceeded from there to the region of Evanston, Wyo., in 

 order to examine the coal-mhies. September 23, the rest of the party 

 reached Eort Steele and disbanded. So as to comply with the orders 

 which required our return by October 1, a small portion of the district 

 assigned to us remained unsurveyed. During the season wq rode over 

 2,500 miles. The pack-train, in the same time marched 1,500 miles. 



Owing to the protracted, severe illness of Mr. Chittenden, no map has 

 been prepared as yet showing the results of our labors. As no good 

 map of that region exists, furnishing a sufficiently large scale, I am 

 forced to modify the usual arrangement of my report. ~No references 

 can be made to localities which are not represented by the older maps, 

 and descriptions thereof must necessarily suffer. In order to remedy, 

 as far as possible, this want, I have prefaced my report with an itinerary. 

 In this will be found a connected account of the trip, which may aid in 

 making more intelligible the allusions in subjoined pages to the names 

 of places and regions we visited. The report proper is divided into five 

 chapters. Of these, the first treats of the physical and, in part, faunal 

 character of the country surveyed; the second describes the surface and 

 structural geology of the Wind Eiver Eange and the country east of it ; 

 the third treats of the country comprised within the Sweetwater drainage ; 

 the fourth discusses the low southern country ; and the fifth contains a 

 review of the economic geology of the district, besides a " Conclusion." 

 An appendix has been added, containing a catalogue of the minerals 

 found within our district. The study of the coal-mines will be the sub- 

 ject of a separate report. 



Owing to the want of a reliable map, much information has necessarily 

 been omitted which otherwise might have been embodied in this report. 

 The distances given, from point to point, are not measured or calculated, 



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