102 



SCIENCE. 



[N. H. Vol. XV. No. 368. 



the use of this reagent, excepting the one 

 statement in separating Ba, Sr, Ca — from 

 Mg, that 'advantage is taken of the fact that 

 magnesinm carbonate is not precipitated in 

 the presence of ammonium salts and ammon- 

 ium hydroxid.' Surely the connnon explana- 

 tion of these group separations — the success- 

 ive breaking down ammonium double-salts in 

 order of their instability by the reagents 

 ammonia, ammonium sulphide, ammonium 

 carbonate and disodium phosphate — is better 

 than no explanation. It may be objected that 

 recent research has disproved, or at least 

 rendered improbable, the existence in solutions 

 of ions indicating ammonium double-salts. At 

 all events, an explanation on the lines of the 

 above quotation regarding magnesium ion 

 might be given. 



In brief, this book can be cordially recom- 

 m.ended to those students v^ho are trained . 

 from the start by lectures based on Ostwald's 

 'Grundlinien der anorganischen Chemie,' and 

 are taught to look at chemical phenomena 

 chiefly in the light afforded by the dissocia- 

 tion theory. 



E. Eenouf. 



Laboratory Companion for Use with Thurs- 

 ton's Inorganic Chemistry. By W. A. 

 ThurstoNj F.E.S., Lecturer on Chemistry 

 in Clifton College, London, Edward Arnold. 

 1901. Pp. 110. 



The author says in his preface that this 

 little book is a reprint of most of the experi- 

 ments in Part 1 of his 'Inorganic Chemistry' 

 and is to be used only as a laboratory com- 

 panion. It is intended to be used before the 

 study of qualitative analysis is commenced, 

 'and may replace such work altogether in the 

 Evidently it is impossible to criticise this 

 case of those who leave school at an early age.' 

 book without a knowledge of the text-book 

 which it accompanies. It is very different 

 from American laboratory manuals. The 

 author holds it 'most imjaortant that the con- 

 nection between physics and chemistry should 

 be insisted on from the earliest stages.' The 

 first thirty-nine experiments are purely phys- 

 ical with exception of one on the hardness of 

 water, which explains permanent and tem- 

 porary hardness, and gives methods for deter- 



mining the hardness of water ; and this before 

 a single experiment on chemical change has 

 been made. 



The experiments given in the remainder of 

 the book are of more chemical nature, and are 

 interesting-, but seem to laek logical sequence; 

 it is to be supposed, however, that this seeming 

 fault would disappear if the book was used in 

 connection with the author's lectures, and that 

 we have in the book those experiinents which 

 he considers to be of particular theoretic or 

 practical interest to young students. However, 

 the book cannot be recommended as a manual 

 in connection with the text-books in actual 

 use in this country. 



E. Eenouf. 



Chemical Lecture Experiments. By Francis 

 Gang Benedict, Ph.D., Instructor in Chem- 

 istry in Wesleyan University. New York, 

 The Macmillan Company, 1901. 

 This book of 435 pages contains brief, clear 

 instructions for performing a great number 

 of lecture experiments. The instructor who 

 has little apparatus at his disposal and turns 

 to Newth or Heumann for help in illustrating 

 his lecture often finds it impossible to show 

 the experiments described, for laek of appa- 

 ratus. The author has rigorously excluded 

 all costly apparatus, and has yet succeeded in 

 giving so many brilliant and instructive ex- 

 periments as practically to cover the whole 

 course. This renders his book invaluable to 

 instructors in schools and in the smaller col- 

 leges. But this is not all; any lecturer who 

 glances through the book will find much that is 

 new and striking. Especially is this true of the 

 e.xperiments on metals, which have received 

 such scant attention in the earlier books. The 

 reviewer has Dr. Benedict's book in use and 

 finds it a valuable supplement to Newth and 

 Heumann. 



Edward Renouf. 



GENERAL. 



'The Fauna and Geography of the Maldive 

 and Laccadive Archipelagoes, being the ac- 

 count of the work carried on and of the col- 

 lections made by the expedition during the 

 years 1899 and 1900,' is now in course of pub- 

 lication in 'Cambridge at the University 

 Press.' Part I. of the first volume appeared 



