REPORT OF ASSISTANT SECRETARY. 85 



the printer during the year, and that copy has been prepared for about 

 five hundred more. The card catalogue of the exhibition series has been 

 kept up to date, and a limited number of cubes of building stones have 

 been cut. About two hundred thin sections were xu-epared, and over 

 three thousand five lumdred duplicate specimens identified, labeled, and 

 laid aside for future use. It is proposed to sort out and prepare for dis- 

 tribution all the duplicate material in the storeroom, with a view to 

 utilizing this space for the study series, the latter having outgrown its 

 present accommodations. A large proportion of the exhibition cases 

 in this department are floor uprights, and have no space for storage. 



A number of the exhibits require rearranging, but this matter will 

 be deferred until the question of erecting balconies shall have been 

 decided. The exhibition series is fairly well labeled, although many 

 typewritten labels are at present in use. 



The investigations of the curator have consisted mainly of studies 

 relating to rock weathering and to the composition, character, and 

 origin of material belonging to the nonmetallic economic series. He 

 has devoted special attention to asbestus, ochres, and soapstones. 

 About fifty analyses have been made in connection with investigations 

 relating to rock weathering and the formation of soils. 



A considerable number of specimens, including many thin sections 

 of rocks, have been lent to various persons for study. Reference to 

 these transactions will be found in another place. 



Among those whose cooperation has been of value during the present 

 year the name of Mr. F. W. Crosby, of this city, should be mentioned. 

 The department is also indebted to the United States Geological Sur- 

 vey for a large proportion of the most valuable material acquired. 



Five papers have been published by Dr. Merrill during the year, 

 three of which appeared in i)ublications of the National Museum. 



Regarding the future development of the department, the curator 

 states that the quality of the material in the collections could in many 

 instances be improved by substituting new specimens, but that desir- 

 able specimens can, as a rule, be obtained only by purchase or by the 

 employment of a paid collector. Occasionally, however, such specimens 

 are to be secured by exchange. 



The present condition of the collections is indicated in the following 

 statement: 



The catalogue entries show that one thousand one hundred and sixty-two speci- 

 mens have been received during the year. This inchides both exhibition and study 

 material. It does not, however, include the live hundred and odd microscopic slides, 

 which are never catalogued. Several of the entries are those of collections includ- 

 ing from one to several specimens each. 



Estimated number of specimens in the collection: 



Exhibition series 23. 097 



Study series 28 911 



Microscopic slides 4, 700 



Duplicates of all kinds 15, 541 



Total 72, 249 



