MINERALlXn^ Foil 1887 AND 1888. 



Hv Kdwari) 8. Dana. 



GENERAL WORK IN MINERALOGY, 



The wide interest felt during- tlie last few years in the general sub- 

 ject of microscopical niiueralogy, and the advance made in this field, 

 are well shown by the number of new worlds that have recently ap- 

 peared which are devoted to this line of research. It has been in the 

 allied department of petrography that the work has been most actively 

 done a!id the i)rogress tnade, but the result has been to bring about a 

 most important advance in the instruments an<l methods of study ap- 

 plied to mineralogy proper. The works of Ilosenbusch and Zirkel, (1873,) 

 were the pioneers in this direction, and since then the workers have 

 been many and the progress made rapid. A second edition of the work 

 of Kosenbuscb was published in 1885, and now an English edition^ has 

 been given to students in this country and England by J. P. Iddings. 

 In this translation the original work a[)poars in somewhat abridged 

 form, but not so much so as to diminish its ^•alue, while making it rather 

 more convenient of use. All that is essential has been retained, in- 

 cluding tlie large number of fine plates of microphotographs. Another 

 work of similar cliaracter is that of liutley.- The methods of studying 

 minerals with the microscope are given systematicallj', with the charac- 

 ters especially of those species which enter into the f«rniation of rocks. 

 A book of rather wider scoi)e and more profound character is that of 

 Michel-Levy and Lacroix.^ The first author has already made impor- 

 tant contributions in this field, and the Mineralogie micrographique by 

 Fouqud' and 31. -Levy (1879'j is one of the most exhaustive memoirs that 

 has been published. In the present volume the author introduces some 

 of the results of his former labors ; for instance, on the variation of the 



1 Microscopical Pliysiograpliy of Kock-nial\in<i; Jfiiicials, and aid 1o (be Microscopi- 

 cal study of Rocks, by H. Roseubiiscb. Translated and abridged for use in scliools and 

 colleges, by Josepb V. Iddings. :333 pp., 2() plates. New York, 1880. J. Wiley &. Sous. 



^ Rock-foruiing Minerals, by Frank Riitley, F. G. S. 252 pp. London, 1888. 

 Thomas Mnrby. 



"Les Min<5ranx des Roches: (I) Application des nicthodes niineralogiqnes et chi- 

 mitines Jl leur <!tnd(; uiicroscopiqne, par A. Michel-Levy; (2) Donndes i)hysiqne3 et 

 optiques, par A. Michel-L6vy et Alf. Lacroix. o34 pp. Paris, 1888. Baudry &. Cie. 



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