September 4, 1919] 



NATURE 



anneal so as to withstand the strain of laboratory 

 use nothing was known at all. 



The researches which are now republished relate 

 mainly to the practical class of problems. The 

 seven papers on the testing- of laboratory glass- 

 ware contain information which has been of the 

 greatest value to glass manufacturers. They 

 should also be very carefully studied by everyone 

 engaged in analytical work. The attention of 

 chemists and physicists is also directed to some 

 interesting pap>ers relating to the calibration of 

 volumetric apparatus and to blowpipe work. 



Experimental work in connection with fefrac- 

 torv materials, furnace problems, etc., is also 

 being undertaken, but'^nly preliminary notes on 

 the results are as yet available. 



The publication contains an account of the 

 educational activities of the department, which 

 includes a school of instruction in blowpipe work. 



M. W. T. 



PHYSICAI. CHEMISTRY. 



(i) Text-book of Physical 'Chemistry. By Prof. 

 A. T. Lincoln. Pp.' viii+ 547. (London: G. G. 

 Harrap and Co., Ltd., 1918.) Price 125. 6d. 

 net. 



(2) Outlines of Theoretical Chemistry. By Dr. 

 F. H. Getman. Second edition, thoroughly 

 revised and enlarged. Pp. xvi + 539. (New 

 York : John Wiley and Sons, Inc. ; London : 

 Chapman and Hall, Ltd., 1918.) Price 165. 6d. 

 net. 



IN the matter of text-books, physical chemistry 

 seems to be coming into its own. It is a 

 healthy sign. Not, indeed, that mere numbers 

 of text-books are any trustworthy measure of the 

 growth and vigour of a science, nor is the un- 

 restricted compilation of them to be encouraged, 

 but physical chemistry is a relatively youthful 

 science, and there is still ample room for in- 

 dividual exposition of the subject. 



We have Ijefore us two general text-books of 

 physical chemistry of moderate size and scope, 

 and it may be said at once that both can be 

 recommended to students who are commencing 

 the subject. In books of this kind the great 

 difficulty for the writer is to know what to 

 exclude, for, of course, much has to be excluded, 

 and no very detailed discussion of any problem 

 is possible. The two books, although of much 

 the same " standard," naturally exhibit their in- 

 dividuality in this respect. There is one point 

 which should not be overlooked : both books are 

 by American authors. It is evident that physical 

 chemistry is taken much more seriously in 

 America than it is in our own country. The fact 

 is that the Americans, like the Germans before 

 them, have realised the fundamental importance 

 'if physico-chemical thinking, not only for advance 



n the theoretical side, but equally so for technical 

 and industrial progress. 



(i) Prof. Lincoln's book is well written, and the 

 fundamental principles are clearly developed and 

 explained. Considerable attention is paid to the 

 laboratory side of the subject. There are a few 



NO. 2601, VOL'. 104] 



historical references, which give added interest 

 to the text. Without going into detail, it may 

 be said that optical properties are particularly 

 well treated, as is also the general problem of 

 heterogeneous equilibrium — e.g. the phase rule 

 and its manifold applications, the principles of 

 fractional distillation, and the solubility relations 

 of three components. (In the last connection a 

 particularly good account is given of the use of 

 the triangular diagram.) There is likewise a 

 fairly comprehensive discussion of colloids, of non- 

 aqueous solutions, and of the ionising power of 

 a solvent. Except in a few sections, only the 

 most elementary mathematics is employed. This 

 makes the book very suitable for those beginning 

 the subject, but, of course, limits its scope. There 

 are a few misprints — e.g. Frick for Fick on 

 p. 434 — and a rather remarkable statement on 

 p. 378 in connection with hydration, which is not 

 quite what the author intends. The absence of 

 a name index is perhaps a drawback, and the 

 use of the term heat-tone as a translation of 

 JVdrmetdnung is to be deprecated. 



(2) Dr. Getman 's book, which now reaches 

 its second edition, is an excellent exposition oif 

 physical chemistry for those commencing the 

 subject. Again only elementary mathematics is 

 used, and, although numerous thermodynamical 

 results are quoted and applied, the author has not 

 attempted any systematic treatment of the prin- 

 ciples of thermodynamics which would have taken 

 him beyond the general aim and scope of the 

 book. It may be mentioned that the subject of 

 conduction of electricity through gases is given 

 much more prominence than is usual in a book 

 of this kind. The same thing is true of the 

 subjects radio-activity, atomic structure, polarisa- 

 tion, and photochemistry. The results of modern 

 research have been incorporated in a skilful 

 manner, and the student is frequently referred to 

 original sources for further information. The 

 presentation of the whole subject is consequently 

 very much up to date. Each chapter is furnished 

 with a set of problems which will be of good 

 service in enabling the student to grasp 

 thoroughlv the meaning of what he reads. 



W. C. McC. Lewis. 



OUR BOOKSHELF. 

 Text-book on Practical Astronomy. By Prof. 



George L. Hosmer. Second edition, revised. 



Pp. ix + 205. (New York : John Wiley and 



Sons, Inc.; London: Chapman and Hall, Ltd., 



1917.) Price gs. 6d. net. 

 The professed object of the author was to satisfy 

 the requirements of civil engineering students, 

 who are unlikely to take up a more advanced 

 study of astronomy, and to produce a text-book 

 intermediate between those formally devoted to 

 astronomy and geodesy, and the short chapter 

 on astronomy generally to be met with in works 

 on surveying. By the lucidity of the explana- 

 tions and the simplicity of the general treatment 

 of the subject, the book seems well adapted to 



