u 



F. GEOGRAPHY. 275 



Civilian Assistant Gilbert Thompson, Chief Topographer. 

 " Frederick A. Clark, Chief Topographer. 



E. J. Sommer, Topographer. 

 J. C. Spiller, Topographer. 

 R. J. Ains worth,* Topographer. 

 William A. Cowles, Asst. Topographer. 



F. O. Maxson, Asst. Topographer. 

 William R. Atkinson, Asst. Topographer. 

 William H. Rowe, Asst. Topographer. 

 Francis Carpenter, Asst. Topographer. 

 Dr. O. Loew, Mineralogist. 



G. K. Gilbert, Geologist. 

 W. W. Hance, Assistant Mineralogist. 

 H. W. Henshaw, Ornithologist. 

 C. A. Aiken, Ornithologist. 

 T. H. O'Sullivan, Photographer. 

 J. B. Mi nick, Meteorologist. 

 John E. Weyss, Draughtsman. 

 Charles Herman, Draughtsman. 

 J. C. Lang, Draughtsman. 

 F. M. Lee, Computer. 



EXPLORATIONS OF DR. HAYDEN IN 1874. 



Owing to the delay in the passage of the appropriation 

 bills, various parties of the Survey could not take the field 

 until July ; but this was in one respect an advantage, as the 

 assistants were thereby enabled to prepare for publication 

 the information collected during the long field season of 1873. 

 By the wording of the appropriation, Dr. Hayden was assign- 

 ed to the survey of Colorado Territory. The field parties, 

 eight in number, were fitted out at Denver; that of the Chief 

 Geologist, Dr. Hayden, making detailed studies of certain 

 areas for the solution of problems of special importance. 



The party of the Geographer of the Survey, Mr. James T. 

 Gardner, was engaged in carrying on the primary triangula- 

 tion on which the maps are based. The party of the Quar- 

 termaster, Mr. James Stevenson, was chiefly occupied in sup- 

 plying the various parties with provisions and stores. A 

 photographer, with a party under Mr. W. II. Jackson, and 

 four surveying parties, under Mr. A. D. Wilson, Mi-. A. R. 



* Accidentally killed. 



