84 Scientific Intelligence. 



many tigs, in text. Geneva, 1902.) — In addition to the more 

 technical researches in geology comprising the major portion of 

 this volume, it contains also a general account of the region 

 studied, of its physical geography, its orography, hydrography, 

 sketches of its fauna, flora, inhabitants, etc. 



The second part of the work treats of the geology and petrog- 

 raphy of Mount Koswinsky and the concluding portion is devoted 

 to a similar study of the small mountain Katechersky. The 

 geology is chiefly the description of the occurrence of the various 

 igneous rocks of the region, which are quite fully described in the 

 petrographical portions of the memoir. They comprise various 

 types of mostly basic rocks, diabases, gabbros, dunites, etc., and 

 diorites, pyroxenites, etc., occurring in dike forms. Of these 

 rocks perhaps the greatest interest attaches to a type of pyrox- 

 enites called If osteite by the author. It is a melanocratic, granu- 

 lar rock composed of varieties of pyroxene, olivine, hornblende, 

 chromiferous spinels and magnetite; the latter mineral plays the 

 part of the xenomorphic cement. 



Several analyses of the different types of koswite are given, 

 from which we select the two following : 



Si0 2 Ah0 3 Fe 2 3 FeO MgO CaO Ign. MnO Cr 2 O s 



(a) 41-44 5-80 10-46 9-93 13-36 19'53 0'22 0'05 0-57 = 10136 



(b) 40-15 4-60 12-24 10-87 15-01 17-26 0'40 ... 0-58^101-11 



Very noticeable in these is the enormous amount of iron and the 

 large amount of lime in comparison with the magnesia ; these are 

 magmas of types quite distinct from those of most of the perido- 

 tites. l. v. p. 



4. Mineralogy ; by Henry A. Miers, Professor of Mineralogy 

 in the University of Oxford. 8vo, pp. 584. London, 1902 (The 

 Macmillan Co.). — As stated by the author in his preface the vol- 

 ume is not intended as an exhaustive book of reference, but 

 rather a treatise in which the student will find all that is required 

 for an elementary acquaintance with the subject of mineralogy, 

 the species described being those which may be found in all 

 museums, and most of which may be collected by the students 

 themselves. Special stress is laid upon accurate measurements 

 and determinations, and the intelligent use of the goniometer and 

 microscope. After a brief introduction the subject of crystal- 

 lization is treated in a thoroughly scientific manner, yet too 

 briefly, it is believed, to satisfy the wants of elementary students. 

 The chapters on the regular conjunction of crystals, on vicinal 

 faces, on the measurement of crystals and on the physical prop- 

 erties characteristic of crystals are brief, but admirably illustrated 

 and full of useful suggestions. The chapter on the optical prop- 

 erties of crystals is one of the best features of the book, and is a 

 very exhaustive and suggestive presentation of this most import- 

 ant subject. By the use of the indicatrix many obscure and per- 

 plexing phenomena of uniaxial and biaxial crystals are explained. 

 Following are short chapters treating of the general physical 

 properties of minerals, chemical properties, isomorphism, pyrog- 

 nostic and microchemical tests, and spectroscopic examination. 



