144 ACCOUNTS, ETC., OF THE BRITISH MUSEUM. 



General. 



Descriptive catalogues of the specimens of Plagionite and 

 Wolfsbergite have been prepared, and those of Iron Pyrites 

 and Zinckenite have been brought up to date. Goniometrical 

 determinations have been made also on specimens of Blende, 

 Stibnite, Tetrahedrite, Enargite, Fluor, Cerussite, Calcite, 

 Epidote, Wolfram, Anglesite and Vivianite. 



In the chemical laboratory sixty doubtful minerals have 

 been qualitatively analysed and determined, and quantitative 

 analyses have been made of two new Brazilian minerals of 

 remarkable chemical composition — Derbylite, a titano-anti- 

 monate of iron, and Zirkelite, a titano-zirconate of calcium 

 (containing also thorium, cerium, iron and uranium in small 

 proportion). 



The selection and arrangement of the series of rock- 

 specimens in six window-cases on the northern side of the 

 gallery to form an " Introduction to the Study of Rocks " has 

 been completed : upwards of 500 labels have been designed 

 for these specimens and have been printed. 



The numerous gaps in the typical series of rocks occupying 

 the 11 window-cases on the southern side of the gallery have 

 been filled up with specimens. 



In connection with the slip-catalogue of the rock-sections, 

 159 micro-sections have been examined. 



A microscopical examination of a group of rocks from the 

 island of Fernando Noronha belonging to the Monchiquite 

 group (Rosenbusch) has been made, and an account prepared 

 for publication. 



Crystals and crystal-models have been selected and arranged 

 in the two wall-cases at the western end of the gallery. 



The series of large specimens of minerals has been extended 

 to fill the three wall-cases in the Pavilion, and it has thus 

 become possible to adopt the same arrangement for the species 

 as is used in the gallery ; 57 large specimens have been 

 selected, mounted on separate pedestals and labelled for this 

 purpose. This re-arrangement has made it possible to place 

 those large specimens of minerals, which remain in the glazed 

 ends of the cases and on separate stands throughout the 

 gallery, near the smaller specimens belonging to the same 

 species. 



The larger rock-specimens, including the specimens of 

 flexible sandstone, have been arranged in a wall-case at the 

 eastern end of the gallery. 



The re-arrangement of the mineral specimens in the drawers, 

 rendered necessary by the growth of the collection, has been 

 continued. 



One hundred and fifty-two micro-sections of minerals and 

 rocks, and two of meteorites have been prepared, and a large 

 specimen of fossil wood has been cut. 



The " Introduction to the Study of Meteorites " and the 



" Introduction 



