REPORT OF THE SECRETARY. 51 



Museum of the Agricultural Department, iu accordance with the ar- 

 rangement to render that establishment the depository of such objects ; 

 while to the Army Medical Museum many hundreds of human crania 

 have been transmitted under a similar understanding. Several special- 

 ists, in addition to those mentioned, have received material for their 

 investigation." 



Tucson Meteorite. — Among the objects of special interest in the Na- 

 tional Museum is a very large meteorite from Arizona, of which an ac- 

 count has been given in previous reports. For the possession of this 

 specimen the Institution is principally indebted to Dr. B. J. D. Irwin, 

 surgeon of the United States Army, who, although it had been seen by 

 other travelers, was the first to conceive the idea of having it transferred 

 to the Smithsonian Institution. In carrying out this proposition he 

 was assisted by the generous co-operation of several persons and trans- 

 portation companies. Owing to an imperfect history iu regard to 

 obtaining this interesting specimen, a label was affixed to it of which 

 complaint was made by Dr. Irwin. After a review of all the facts of the 

 case, and in accordance with his suggestion, the specimen is now labeled 

 as follows : "The Tucson Meteorite presented to the Smithsonian Insti- 

 tution by Dr. B. J. D. Irwin, U. S. A., and transported from Tucson, 

 Ariz., to Washington free of cost by S. Ainsa, the Flint & Halliday 

 steamers, the Pacific Mail Steamship Company, and the Panama Bail- 

 road Company." 



We hope this inscription will be satisfactory to Dr. Irwin and do 

 justice to all concerned in furnishing the National Museum with one of 

 its most interesting specimens. 



GOVERNMENT EXPLORATIONS AND SURVEYS. 



The following is a brief account of the principal explorations of the 

 Government in 1875, from which specimens will be derived for increas- 

 ing the collections of the National Museum. 



The United States Geological and Geographical Survey, uuder the di- 

 rection of Professor Hayden, during the season of 1875, continued its 

 work of the two previous seasons in Colorado, completing the southern 

 and southwestern portions, including a belt fifteen miles in width, of 

 Northern New Mexico and Eastern Utah. The entire force of the sur- 

 vey was divided into seven parties for special duty, four of which were 

 assigned to specific areas for the performance of topographical and geo- 

 logical work, one party attended to the primary triangulation, a second 

 collected photographic views of the most interesting scenery and ancient 

 ruins, while a third transported the supplies to the various districts. 



The entire area surveyed during the summer of 1875 embraced about 

 thirty thousand square miles. There now remains only the northwest 

 corner of Colorado to be examined, prior to the completion of six 

 sheets of the physical atlas which has been designed by the Depart- 



