November 8, 1912] 



SCIENCE 



637 



sis; tlie second part, to the occurrence, prepa- 

 ration, properties and reactions of the sugars 

 and their allied derivatives. 



Part I., which covers about 500 pages, dis- 

 cusses the sampling of sugars and sugar prod- 

 ucts; determination of moisture; densimetric 

 analysis; the refractometer and its applica- 

 tions; theory and practical application of 

 polariseopes ; the specific rotation of sugars; 

 methods of simple and invert polarization; 

 qualitative methods for the identification of 

 sugars, and methods for the analysis of sugar 

 mixtures. 



Part II., in some 260 pages, deals with the 

 formation of sugars in nature, and their 

 classification; the mono-, di-, tri- and tetra- 

 saecharides, the amino-sugars, cycloses and 

 the sugar alcohols and sugar acids. 



The sugar-tables, which, for convenience, 

 are grouped together in an appendix of 100 

 pages, are paged independently of the rest of 

 the volume. They may therefore be bound 

 separately for laboratory use. 



An idea of the painstaking care with which 

 this work has been prepared may be gained 

 from the fact that the index alone fills 69 

 pages. The style in which the book is written 

 is admirably clear and concise; the merits and 

 demerits of the various methods given are 

 objectively and dispassionately stated; the 

 methods endorsed by the International Com- 

 mission for Uniform Methods of Sugar Analy- 

 sis — of which Commission Dr. Browne is a 

 member — receive full consideration through- 

 out. The text is illustrated by a number of 

 well-chosen and well-executed cuts, and the 

 general excellence of the typography and 

 make-up of the book reflect great credit on the 

 publishers. 



Dr. Browne is certainly entitled to the most 

 cordial appreciation and congratulations of 

 his fellow-workers on this classic contribution 

 to their store of knowledge. 



F. G. WlECHMANN 



Popular Guide to Minerals. By L. A. Grata- 

 CAP. New York, D. Van Nostrand Com- 

 pany. 1912. 330 pages, Y4 plates and 400 

 figures. Price $3.00. 



This book, as its name indicates, is intended 

 chiefly for the general reader and student. It 

 is designed largely to assist in the study and 

 appreciation of the mineral collections to be 

 found in our great museums. It is to be re- 

 gretted that popular interest in minerals is 

 by no means as widespread or as active to-day 

 as it was twenty-five years ago and it is to be 

 hoped, therefore, that this book may help to 

 revive the study of minerals and to restore it 

 to its proper place as one of the more inter- 

 esting and popular branches of natural 

 science. 



The book contains a section on crystallog- 

 raphy, followed by a discussion of the physical 

 and chemical properties of minerals. The 

 section devoted to the description of mineral 

 species — in harmony with the purpose of the 

 book — has been entitled, " Guide to Collec- 

 tions." An extensive history of the develop- 

 ment of mineralogy follows and the book 

 closes with a description of the fine Bement 

 mineral collection which belongs to the Amer- 

 ican Museum of Natural History in New 

 York City and of which the author of the 

 book is curator. 



The illustrations comprise first a series of 

 more than seventy plates giving photographic 

 reproductions of some of the finer and more 

 striking specimens in the Bement collection. 

 Mineral specimens offer many obstacles to suc- 

 cessful reproduction in this way and nothing 

 but praise can be said of the results achieved. 

 It is to be regretted that the line figures used 

 in the book, especially in its earlier sections, 

 have not been reproduced as successfully. 



W. E. PORD 



Yale Universitt 



SPECIAL ARTICLES 



ANTAGONISTIC ACTION OF ELECTROLYTES AND 



PERMEABILITY OF THE CELL MEMBRANE 



1. The writer observed years ago that the 

 newly fertilized eggs of Fundulus die in a 5/8 

 m NaCl solution without forming an embryo, 

 while the addition of a very small but definite 

 amount of a salt with a bivalent metal (with 



