APRIL 1, 1897 | 
a Ale RE: 
507 
OUR BOOK SHELF. 
Short Studies in Physical Science. By Vaughan Cornish, 
M.Se. Pp. 230. (London: Sampson Low, Marston, 
and Co., Ltd., 1897.) 
New Thoughts on Current Subjects. By the Rev. J. A. 
Dewe. Pp. 230. (London: Elliot Stock, 1897.) 
Ir may be doubted whether the republication, without 
additions, of articles and reviews contributed to ephemeral 
literature serves any useful purpose. Many, if not most, 
of the articles in Mr. Vaughan Cornish’s book are re- . 
prints of contributions to Anow/edge and The Speaker ; 
but though they are good examples of what popular scien- 
tific articles should be, the fact that they deal to a large 
extent with current topics, necessarily from the point of 
view of information available at the time when they were 
written, and have not been brought up to date, makes 
their republication undesirable. An article on argon, for 
instance, written in February 1895 (February 1894, on 
p- 75, is evidently a misprint), does not contain a satis- 
factory account of argon as we now know it; and a 
similar objection may be raised to the articles on helium 
(written June 1895), on the Réntgen rays (written March 
1896), and on Moissan’s synthesis of diamonds (written 
in March 1894). The reprinting of a popular review ofa 
popular book on astronomy is still more open to objection. 
The papers included in Mr. Cornish’s book deal with 
subjects in the fields of mineralogy, chemistry and 
physics. They contain a certain amount of interesting 
information, and possess the merit of accuracy ; so that 
they may be read with pleasure and profit by the general 
reader who does not mind being a little behind the 
scientific times. 
The Rev. J. A. Dewe’s volume is wider in scope than 
that of Mr. Cornish ; its subjects are social and philo- 
sophical as well as scientific. The five essays in the 
scientific section deal with sea salts and carbonates, the 
nature of heat, the nature of electricity, stellar and 
absolute space, and the science and harmony of smell ; 
while among the subjects of the philosophical chapters 
are free will versus heredity and environment, and the 
dogmatic and scientific accounts of the creation of man. 
The book has a leaning to metaphysics, but many common 
experiments are clearly described, and sound conclusions 
are arrived at from simple arguments. We commend the 
book especially to men of the author’s profession, 
believing that many of them would acquire breadth of 
thought by the perusal of it. For ourselves, we are glad 
to live in the days when a clergyman can calmly discuss 
facts as to similarity that exist between the physical 
structure of the human body and that of the monkey, 
and can say “they lead irresistibly to the conclusion 
that, as far as the physical part of man is concerned, 
no exception was made in the laws of the material 
universe, but that the body of the one slowly developed 
into the body of the other.” 
Vorlesungen tiber Bildung und Spaltung von Doppel- 
salzen. By Prof. J. H. van ’t Hoff. German, by Dr. 
Theodor Paul. Pp. iv + 95. (Leipzig: Wilhelm 
Engelmann, 1897.) 
THE present work is a reproduction of the substance of 
courses of lectures delivered in Amsterdam and Berlin 
in the years 1894 to 1896. It will be very welcome to 
the larger public to which these lectures are thus made 
accessible. They deal almost exclusively with the re- 
searches of the author and his pupils on the formation 
and decomposition of double salts. The original form 
of the lectures has not been retained, the subject-matter 
being treated under three heads. Under the first, the 
behaviour of a sparingly soluble double salt formed by 
the union of two binary salts, with or without water of 
crystallisation, is investigated from the standpoint of the 
NO. 1431, VOL. 55] 
author’s theory of dilute solutions and the theory o 
electrolytic dissociation. The temperatures and pressures 
at which a double salt can exist, its decomposition by a 
solvent, and the influence of the presence of one or other 
of its components on its stability are theoretically in- 
vestigated. 
The second part contains a description of the ex- 
perimental methods used in the study of the de- 
composition of double salts, in determining transition 
temperatures, vapour pressures of the salts and their 
solutions, solubilities, and other quantities of importance 
in investigations of this kind. The methods are all 
original, and this section should be of great service to 
workers in this field of research. In the third part, the 
behaviour of bipotassium copper chloride, hexahydrated 
magnesium potassium sulphate, sodium ammonium and 
sodium potassium racemates, and the right and left- 
handed Rochelle salts are minutely described, and shown 
to be entirely concordant with that theoretically predicted. 
These lectures, thus, carry the investigation of the 
double salts, described in the ‘Studies in Chemical 
Dynamics,” a step further. In the latter book the 
temperature at which the complete change of a double 
salt into its components occurs was fully studied ; here 
the other conditions which affect the existence of double 
salts are taken into account, and the whole of the region 
in which such a salt is capable of existence inves- 
tigated. The book is one with which all who are 
interested in inorganic and physical chemistry should be 
acquainted. 
Practical Electrical Measurements. By Ellis H. Crapper, 
A.LE.E. Pp. xii +125. (London: Whittaker and 
Co., 1897.) 
THE experiments described in this book should be very 
serviceable in imparting a real knowledge of the funda- 
mental principles of magnetism and electricity. Only by 
numerous measurements can a student obtain familiarity 
with measuring instruments and the principles under- 
lying their construction and use. Such work recorded 
in a systematic and intelligent manner is the best train- 
ing a student can have to qualify him for the testing- 
room of electric light and cable stations. The experi- 
ments described are almost entirely quantitative, and 
they include all the usual magnetic and electrical 
measurements made in physical laboratories. The book 
thus not only furnishes a course in electrical testing, but 
may also be profitably used by advanced students in 
Organised Science Schools and Technical Schools. 
Notes of Lessons on Elementary Botany. Prepared to 
meet the requirements of the Code of the Committce 
of Council on Education ; together with an Appendix, 
intended as an introduction to a British Flora. By 
W. Bland. (London and Derby: Bemrose and Sons, 
Ltd., 1897.) 
Tus little book is not altogether devoid of use ; but the 
author has often sacrificed clearness at the shrine of 
ambition, in endeavouring to compress about three times 
too much matter into his pages. Asit stands at present, 
it is fitted to take a place amongst the cram-books, and, 
like them, is often obscure, or even worse, from the point 
of view of accuracy. We should pity the child who en- 
deavoured to get on without a large addition of oral 
help. Many of the figures might well be improved. 
Dr. Nansen: the Man and his Work. By Frederick 
Dolman. Pp. 108. (London: Society for Promoting 
Christian Knowledge, 1897.) 
Tuis is a very simple story of some of Dr. Nansen’s 
characteristics, schemes, and successes. It contains little, 
if any, new information. 
