490 Scientific Intelligence. 



180,000 carats a year maybe hoped for. — Centralblatt fur Miner- 

 alogie, etc., pp. 235, 251. 



6. Interferenzerscheinungen im polarisirten Licht. Photogra- 

 phisch auf genommen ; von Dr. Hans Hauswaldt, Dritte Reihe. 

 Magdeburg, 1908. — The scope and value of this work, of which 

 the third series of plates has recently been published, has been 

 somewhat fully presented in the notice of the First Part (on p. 

 397 of volume xviii). This series consists of 72 plates which, in 

 beauty of execution, are fully equal to those which have preceded. 

 The phenomena illustrated are quite varied in character. Some 

 of the subjects covered are as follows : Phenomena in converg- 

 ing polarized light with circular polarizer and analyzer ; various 

 combinations of quartz plates in converging polarized light ; 

 phenomena presented by highly absorptive media as andalusite, 

 also magnesium-platinum and yttrium-platinum cyanides. 



7. Complete Mineral Catalog ; compiled by W. M. Foote. 

 Twelfth edition. Pp. 320. Philadelphia, 1909 (Foote Mineral 

 Company). — This twelfth edition of the Foote Mineral Catalogue 

 appears in much enlarged form and is made attractive by its 

 excellent topography and the introduction of numerous well- 

 executed figures. It gives the names of all recognized mineral 

 species, including those recently described, which will be included 

 in the Second Appendix to Dana's Mineralogy, now in press. 

 The composition of each species is given, and also the more 

 important physical characters. 



8. Introduction to the Study of Hocks ; by L. Fletcher. 

 Brit. Mus. Nat. Hist., Guide to Mus. Coll. Fourth edition. 8°, 

 pp. 155, 1909. — This is a new edition of the guide book published 

 in 1895. Although considerable of the original material has been 

 retained, much new matter has been added to bring the work up 

 to date. The same general grouping of the rocks is retained, 

 but greatly expanded to include recently described kinds and so 

 altered as to make the primary divisions on the mineralogical 

 basis, the secondary ones those of texture. The numbers of the 

 exhibition cases in the Museum are added on the margin, so that 

 specimens illustrating the phenomena discussed may be readily 

 found. Although the work is intended for a definite local pur- 

 pose, at the same time petrographers will find much that is of 

 general interest in it, especially with respect to the author's views 

 on classification. It is clearly and simply written, the subject 

 matter well chosen, and it will without doubt be of great service 

 in the field for which it was designed. l. v. p. 



9. Determination of Rock-forming Minerals ; by A. Johann- 

 sen. New York, 1909 (Wiley and Sons). — In a previous notice 

 of this work (this Journal, vol. xxv, p. 529, 1908), it was stated 

 that a method of cutting the edges of the pages was indicated, by 

 which an indexing was produced to facilitate the use of the 

 tables. In practice this proved cumbersome and may have hin- 

 dered the use of this very useful work. Since then the publishers 

 have devised an extremely neat and efficient method of doing this 



