70 



NATURE 



[November 17, 19 10 



available, which is afforded by the disintegration of 

 the radio-active elements, seems to indicate that devo- 

 lution occurs primarily along the horizontal scries, 

 and that the highest known member of the helium 

 group — the newiy-christened niton — takes its place 

 in the chain of descent along with the other elements, 

 and cannot be reg^arded simply as a by-product. 



Enough has been said, however, to indicate the 

 great interest attached to this short work, and the 

 service rendered by the author in presenting in a 

 collected form the ideas of chemists, enriched by his 

 own suggestions, on this fundamental problem of the 

 science. 



(2) Dr. Smiles treats of a subject much inore amen- 

 able to experiment than the disintegration of the 

 elements, and the perusal of his bulky volume shows 

 how difficult it is to arrive at any but empirical rela- 

 tions between physical properties and chemical con- 

 stitution, even when the effect of everv minute ch.'inge 

 in constitution can be examined experimentally. The 

 work deals with the chief physical properties of the 

 elements and their compounds (with certain excep- 

 tions which have already been considered in other 

 volumes of the series), and provides an extremelv 

 useful compendium of the work which has been done in 

 this connection. The author has, however, not allowed 

 his subject, great as is the mass of detail comprised 

 in it, to overwhelm him, but has throughout paid 

 special attention to the applications which have been 

 made of the knowledge acauired to the solution of 

 problems of constitution, and to the effect of progress 

 in this branch of the subject on the general trend 

 of chemical theory. The interest is further increased 

 by a preliminary clear account of the nature of each 

 physical property in turn, and a historical sketch of 

 the progress of knowledge with regard to it. The 

 author's final conclusion that further advance will 

 depend essentially on a more complete solution of the 

 problem of valency will probably commend itself to 

 most chemists, and there seems little doubt that, as 

 foreshadowed in many parts of' this book, the study 

 of physical properties will be an imjJortant factor in 

 the attainment of this result. 



In his exposition of the general principles of 

 physical chemistry (3), Dr. Philip has aimed at giving 

 an account of the subject which will be of special 

 value to workers in the borderland regions of biology 

 and chemistry, and has therefore adapted his book 

 both in scope and treatment to attain this end. 

 Without anv sacrifice of scientific accuracy, he has 

 given a sound and readable account of the subjects 

 of chief interest to biologists, and has illustrated 

 them wherever possible bv reference to problems of a 

 biological nature. In addition to the ordinary fare of 

 works on elementary physical chemistry, special atten- 

 tion is paid to osmosis, permeability and imperme- 

 ability of membranes, the properties of colloids and 

 adsorption. On the whole, the author has succeeded 

 admirablv in his purpose, and has provided a valuable 

 and interesting introduction to the subject, not over- 

 burdened with detail and almost; free from those 

 mathematical subtleties which are too frequently the 

 despair of biologists. Arthur Harden. 



NO. 2142, VOL. 85] 



CHEMISTR Y FOR FIRST-YEAR STUDENTS. 

 (i) A College Text-book of Chemistry. By Prof. Ira 



Remsen. Second edition, revised. Pp. xxiii + 702. 



(London : .Macmillan and Co., Ltd., 1908.) Price 



los. net. 

 (2) Outlines of Chemistry. A Text-book for College 



Students. By Prof. Louis Kahlenberg. Pp. xix + 



548. (New York : The Macmillan Co. ; London : 



Macmillan and Co., Ltd., 1909.) Price iis. net. 

 (i) 'T^HE first edition of Prof. Remsen 's "College 

 A Chemistry " was somewhat unfavourably re- 

 viewed in these columns [Nature, vol. Ixv., p. 314 

 (1902)], and, unfortunately, most of the faults then 

 pointed out recur in the present edition. Notable 

 exceptions are, however, the treatment of the ionic 

 hypothesis and of the determination of molecular 

 weights from measurements of osmotic pressure. The 

 least satisfactory portions of the work are those deal- 

 ing with physical and electro-chemistry. Even 

 on the purely chemical side there are some 

 passages which might be amended. Thus it is not 

 generally true, as stated on p. 144, that metals can 

 be distinguished from non-metals according to 

 whether they do or do not liberate hydrogen from 

 hydrochloric acid to form chlorides. (A better 

 criterion is, however, given on p. 169.) On pp. i85-(> 

 volumetric analyses are calculated on the objectionabl" 

 system based on a consideration of the weights of the 

 reacting substances in the respective measured 

 volumes, instead of by the straightforward "equi- 

 valent " method. 



These faults are the more to be regretted since the 

 book is in many ways admirably suited for the purport 

 for which it is intended. Thus Chapter V., dealint^ 

 with the atomic theory and the determination (' 

 atomic and molecular weights, is, for the most part, ;: 

 model of clearness. Attempts have been made to 

 bring the work up to date by the insertion of short 

 references to the phase rule, catalysis, the electron 

 theory, radioactivity, &c. Within the scope allowed, 

 the systematic descriptive portion is excellent. The 

 experimental exercises given at the end of each chapter 

 are well chosen ; but, unfortunately, few first-year 

 students in this country would have the time or the 

 laboratory facilities for carrying them out. 



(2) Prof. Kahlenberg's book is, like the preceding, 

 intended for first-year students, and of necessity covers 

 much the same ground ; but there the resemblance 

 ends. The general plan, as set forth in the preface, is 

 to lead up to general theories through the fundamental 

 facts and laws instead of first laying down general 

 propositions and then illustrating these by facts. 

 Accordingly, no mention of the atomic and molecular 

 theories or of chemical nomenclature and symbols is 

 made until the sixth chapter is reached. 



Physical chemistry does not occupy a prominent 

 place in the book ; nevertheless, seeing that Prof. 

 Kahlenberg is practically the only opponent of the 

 generally accepted ionic hypothesis to be taken seri- 

 ously, we turn with interest to the pages dealing 

 with this part of the subject. On p. 429 we find the 

 remark : •" The main difference between the Clausius 

 and Arrhenius theories is that the latter assumes the 



