710 SUMMARY OF CURRENT RESEARCHES RELATING TO 



and microscopy is justified on the ground that " founded on optics and 

 on the observation of objects of nature or of human art, they are in 

 close connection, each requiring only an easy apprenticeship for those 

 who are already familiar with the other." 



The first volume (12 Nos., July-December) contained 84 pages, 

 but in future one part of 16 pages will be published quarterly, the 

 saving thus effected being applied to creating and maintaining a gratis 

 circulating library for the subscribers. 



" Societe Francaise de Microscopie." — The title-page of the 

 first volume of the preceding journal announced that it was the 

 " Bulletin de la Societe Fran9aise de Microscopie," and we were for 

 the moment under the impression that a Microscopical Society had at 

 last been established in France. It appears, however, by an announce- 

 ment in the journal that the constitution of the society is a novel one, 

 as it consists simply of the subscribers to the journal, who are formed 

 by the editor into two groups, one being called the " French Society 

 of Microscopy," and the other the " Photographic Society of France," 

 each with a central group in Paris and local groups wherever the 

 number of subscribers is sufficient. 



Of the constitution of the society only the 1st and 3rd articles of 

 the statutes are at present published : — 



"Art. 1. There is founded, under the name of the "Societe 

 Fran9aise de Microscopie," from among the French or foreign sub- 

 scribers to the ' Journal de Photographic et de Microscopie ' who 

 assent to these statutes, a society for observation, for communications, 

 and exchanges, having Microscopy for their object. It is administered 

 by the director of the journal, who bears the title and performs the 

 duties of secretary of the society. 



" Art. 3. The members of the society pay neither entrance fee nor 

 periodical subscription. Nevertheless, each of the groups of which 

 the society is composed may impose useful expenditure on the group 

 or on the society (!). This expenditure can only be voted for a year." 

 MicrograpMcal Mineralogy. — Under this title the French 

 Ministry of Public Works has published* a livre de luxe, in 4to, with 

 509 pages and 55 plates, by MM. F. Fouque and A. M. Levy. There 

 are opening chapters on the " utility of the microscopical examination 

 of rocks," and on the " history " of such examinations (referring more 

 especially to those of Leeuwenhoek in 1690, Baker and Ledermuller in 

 1764, Daubenton in 1794, Dolomieu and Fleuriau de Bellevue in 

 1800, and others since that date), with directions for "preparing 

 material," on Microscopes for petrological work, and several chapters 

 dealing very exhaustively with the optical properties of minerals. These 

 are followed by directions for the qualitative analysis of rocks, and for 

 extracting elementary minerals from rocks, the first part concluding 

 with an explanation of the deformations and imperfections found in 

 the minerals. The second part (pp. 147-475) is occupied with a 

 detailed description of the various minerals, commencing with quartz. 

 A copious bibliography of 27 pages is appended. 



* Part of the ' Me'moires pour servir a I'cxplication de la Carte Ge'ologique 

 de'taille'e de la France.' 



