MINERALOGY. 233 



Bischof, P. Die Steiasalzwerke bei Stassfurt. [The Salt-works 

 near Stassfurt.] Ed. 2. Map and plate. 8vo. Halle. 



Brezina, Dr. Aristides. Das Wesen der Isomorphie und die Feld- 

 spatlifrage. [Isomorphism and the Felspar Question.] Min. Mitt. 

 Heft i. pp. 13-30, Heft iii. pp. 137-152, with fig. 



The two parts here published deal with the theory of isomorphism. 



Broadhead, G-. C. Occurrence of Bitumen in Missouri. Trans. Acad. 

 Sci.^t. Louis, vol. iii. no. 2, pp. 22-1-226. 



Gives the geographical distribution of bitumen in Missouri ; the 

 quantity seems to increase in going southwards. It occurs in Coal 

 Measure sandstones and in Lower Carboniferous Limestone. Notes of 

 borings are given. F. W. E. 



Brown, Dr. R. On Magnetic Iron -Sand from shores of Lochfyue. 

 Proc. R. Fhys. Soc. Min. Session 1874-75, p. 28. 



Contains more iron than a similar sand from Bogamy Point, Rothesay 

 Bay. A divergence of the compass is said by captains of small coasters 

 to take place near the point where the principal deposit lies. R. E., Jun. 



Brush, George J. Manual of Determinative Mineralogy ; with an 



Introduction on Blow-pipe Analysis. Pp. iv, 104 ; 22 figs. 8vo. 



New York. 



Describes the apparatus and reagents used in blowpipe-analysis ; gives 



a systematic course of qualitative analysis : an alphabetical list of 



elements and compounds, with the most characteristic blowpipe and 



other reactions ; and a series of tables for the determination of mineral 



species by means of simple chemical experiments in the wet and dry 



way, based on Yon Kobell's well-known Tafeln. F. W. R. 



Burkart, Doctor Jose. Examen y Clasificacion de algunas Especies 

 Minerales de Mexico. [Examination and Classification of some 

 Mexican Minerals.] Naturaleza, t. iii. no. 13, pp. 248-253, no. 

 15, pp. 288-291. 



Castillo, Antonio del. Noticias sobre los Criaderos de Grafita 6 

 Plombagina de Mexico, y su Explotacion. [Notes on Deposits of 

 Mexican Graphite, and their working.] Naturaleza, t. iii. no. 14, 

 pp. 275-281. 



Church, Prof. A. H. Notes on the Specific Gravity of Precious Stones. 

 Geol. May. dec. 2, vol. ii. pp. 320-323. 



The stones are as follows (the figures in brackets being the numbers 

 of specimens experimented on) : Adularia (1), Beryl (4), Chrysoberj'l 

 (4), Chrysolite (2), Garnet (11), Quartz (9), Sapphire (3), Spinel (4), 

 Topaz (11), Tourmaline (6), Zircon (15). W. T. 



. On the Composition of Autunite. Joia-n. CJiem. Soc. pp. 109- 



112. 

 Contains 5 original analyses of Autunite, made on two French 



