266 



REPORT OF NATIONAL MUSEUM, 1891. 



Supposed kaolin; sent bj' E. W.itrous, Weiser, lihiho. No. 1173. 



Ores for identification; sent l>y Henry Clause, Pliebe, Tenn. No. 1179. 



Graphite; sent by J. D. Schneider, Allentowu, Pa. No. 1180. 



Material for determination; sent by Marion Moyers, Compensation, Tenn. No. 



1186. 

 Supposed pliosplnite; sent by F. M. Westerfelt, Rural, Fla. No. 1201. 

 Ores for determination; sent by I. Bradon, Pbebe, Tenn. No. 1203. 

 Material for assay; sent by W. R. Fiudly, Hoodsport, \N'asli. No. 1211. 

 Supposed fossil; sent by W. S, Danfortli, Boulder, Colo. No. 1220. 

 Material for assay; sent by L. Ballard, Lindside, "\V. Va. No. 1221. 

 Ores for determination; sent by O. P. Sybest, Ravenwood, "\V. Ya. No. 122.">. 

 Supposed tin ore; sent by Emil Wilvert, Sunbury, Pa. No. 1236. 



It will be seen from tlie above tliat out of a total of 452 accessions 

 coming to tlie entire Museum for examiuatiou, this department alone 

 received l.''>2, or nearly oO j^er cent. Tlie curator is often called upon 

 to give information regarding material l)rougl!t to the Museum for iden- 

 tification. 



A new case lias been built across the east end of the west south rauge 

 and which affords accommo<bitions for the collections of rocks forming 

 minerals, structural, color, and sj^ecific gravity series, as well as the 

 larger collections in historical geology. 



The work of installing the exhibition series is always more or less 

 experimental, ami the curator is, or should be, continually striving to 

 introduce methods whereby the most pleasing effects are produced, as 

 well as each object brought into such position as shall render its points 



of interest most readily seen. Thus 

 a considerable amount of time is 

 consumed in what may be called 

 ex])erimental work. In those cases 

 wlieie economy of space demands 

 two or more rows of specimens on 

 each shelf, it is often a matter of 

 some dirticulty to so place the ob- 

 jects in the ])ack row that they can 

 be readily seen. The prevailing 

 method has been to simply raise 

 t hese specimens a little above those 

 in tlie front row by means of blocks 

 of wood. This, however, proved scarcely suflicient in the case of tlie 

 ore and petrographic collections, and therefore a bent wire bracket 

 was devised, which, by means of a small Avire staple, is readily at- 

 tached to the wooden block, and which then holds the specimens stand- 

 ing, inclined at an angle of GO to 80 degrees, as shown in the accompany- 

 ing diagram. The siiecimens on the front roMs being laid flat, both 

 series are thus rendered equally conspicuous. 



The cost of these wires in Washington is but from 1 to 2 cents each, 

 and they have been found of the greatest utility. 



Diagram 2.— Bent-wire lioklei' ami block 

 for exliibiting spocimens of rotka. 



