REPORT OF ASSISTANT SECRETARY. 39 



has been thoroughly overhauled, with a view to elimiuatiDg all worth- 

 less specimens. 



The preparation of sets of duplicate material has been commenced, 

 in order to meet the requests of educational institutions for collections 

 of this kind. 



Special researches have been made upon the Montville serpentine 

 and the peridotite from Little Deer Island on the coast of Maine, and 

 upon a new meteorite from California. Papers relating to these speci- 

 mens have been prepared for publication in the Proceedings of the 

 National Museum. 



The curator has paid especial attention to the stratigraphic, struct- 

 ural, and dynamical geology exhibition series, and many important 

 additions have been made during the year. In the annual report of 

 this department, seventeen accessions are mentioned as of especial im- 

 portance, among which are a large collection of •eruptive rocks, miner- 

 als, veins, and joint formations collected by the curator in New Jersey, 

 Ehode Island, Massashusetts, and Maine, and an interesting series of 

 Devonian marbles and eruptive rocks sent in exchange by Mr. E. N. 

 Worth, curator of petrology in the Plymouth Institute at Plymouth, 

 England. Valuable contributions have also been received from officers 

 of the U. S. Geological Survey. 



During the year, 1,000 specimens have been received. 



METALLURGY. 



The energies of the curator, Mr. F. P. Dewey, and his assistants, 

 have been devoted during the year to work incident to the change in 

 the location of the exhibition space of the department. A complete 

 reorganization of the geographical series of ores has been effected, and 

 some changes have been made in the systematic collections in economic 

 geology and metallurgy. The curator has prosecuted special researches 

 in regard to the perfecting of the Hampe method of determining sub- 

 oxide of copper in metallic copper, in order to carry on a further inves- 

 tigation upon the refining of pig-copper. He has also made a complete 

 chemical examination of the large collection from the Lone Elm Smelt- 

 ing Works at Joplin, Missouri. To accomplish this it was necessary to 

 make sixteen chemical analyses. 



During the year, 101 accessions were received. Of this number, 72 

 consisted of specimens sent for examination and report. Two impor- 

 tant collections were contributed by the U. S. Geological Survey. One 

 of these was collected by Mr. J. S. Curtis in connection with the 

 preparation of a report upon the silver-lead district of Eureka, Nevada ; 

 the other was collected by Mr. S. F. Emmons, who is preparing a report 

 upon the geology of Leadville, Colorado. 



The total number of specimens in the department is about 51,000, of 

 which 18,000 are in the exhibition series. 



