November 2, 1899] 



NATURE 



IS a natural parent of gas engines, and it seems possible 

 that some smokeless explosive might be used for driving 

 motor-cars ; for though the fuel would be heavy the 

 mechanism might be simple, and the opportunity for 

 varying the work done at each stroke very considerable, 

 so that its adaptability to the circumstances of motor-car 

 propulsion would be great. 



The work is so full of interesting matter that it would 

 be hopeless, in a short review, to call attention to the 

 tenth part of its contents. Accounts of Egyptian, Greek, 

 Roman and Alexandrian inventions are followed by ac- 

 counts of those of the Byzantines, Arabians and of the 

 Middle Ages. Science progressed slowly in these dark 

 ages. Ten pages suffice for the whole of the inventions 

 of Europe for this thousand years. While the energies 

 of mankind were divided between fasting and praying 

 for others, and fighting and preying on others, there 

 was but little time or opportunity for the study of 

 nature. With the sixteenth century the tide of evolution 

 of the means of studying nature had begun strongly to 

 flow. At first rising slowly it has in this last century 

 come like the bore on the Amazon, almost overwhelming 

 us with the rapidity of its development. 



G. F. F. G. 



OUR BOOK SHELF. 

 The Diseases of Children. By G. Elder and J. S. Fowler. 



Pp. xii -t- 391. (London: C. Griffin and Co., Ltd., 



1899.) 

 Few things show more clearly the advance made in the 

 practice of medicine within the last thirty years than the 

 way in which the diseases of children are now regarded 

 as compared with the place assigned to them a generation 

 or so ago. 



It was thought then that to attend to the common 

 ailments of women and children, those of children 

 especially, was work that scarcely demanded the pre- 

 paration of a complete medical curriculum. Even a 

 professor of medicine at one of the leading universities 

 had the courage within living memory to say publicly 

 that a two years' course would be quite enough for suc- 

 cessful practice "among women and children." 



Nowadays all this has changed. It is universally re- 

 cognised that the physiology and the ailments of men 

 are not a whit more intricate than those of women, and 

 that both are simpler than those of children. To treat 

 young children successfully requires, not only all the 

 training and knowledge every good practitioner ought to 

 posess, but important additions. Some of these ad- 

 ditions, moreover, are natural gifts which cannot be 

 acquired by any amount of training or patience. To be 

 able to read a child's nature easily is as much a gift as a 

 fine ear for music. Some men and women have it, and 

 many more are completely without it. To succeed as 

 specialists in children s ailments it is essential not to be 

 without it. 



The work before us is intended mainly for students, 

 and one of its aims is to show them how and what to 

 observe. A large part of the book is concerned with the 

 physiology of growth, of nutrition and of the nervous 

 system. Many of the illustrations are specially good. 



The sections devoted to the study of diseases of the 

 various systems, digestive, circulatory, &c., suffer from 

 the condensation necessary in a work of this size. It is 

 a hopeless business to try to make pemmican attractive. 

 But, on the other hand, pemmican has its uses, and a 

 book small enough to be carried to the bedside in a 

 hospital ward will often help a student more, for a time, 



NO. 1566, VOL. 61] 



than larger and more interesting works could do. These 

 he will read later and with a mind more ready to ap- 

 preciate them. ^ 



Fowler and Elder's manual will not displace Ashby 

 and Wright's on the same subject, but it is a sound and 

 trustworthy guide in a difficult department of medical 

 practice. 



Analyses ^lectrolytiques. By Ad. Minet. Pp. 170 



(Paris : Gauthier-Villars, Masson et Cie, 1899.) 

 This handy volume, which appears as one of the 

 " Encyclopedie scientifique des Aide-Memoire," affords 

 another indication of the continually increasing applica- 

 tion of electricity to chemical analysis. About a third of 

 the book is devoted to the description of apparatus used 

 in electro-chemical analysis and to general considera- 

 tions of a practical and theoretical nature. The latter 

 contain certain inaccuracies which indicate that the 

 author is not conversant with the advances made during 

 the last decade, in regard to our knowledge of the nature 

 of salt solutions on the basis of the theory of electrolytic 

 dissociation. 



The second and third chapters deal respectively with 

 the analysis of metalloids and with the quantitative de- 

 termination of the metals when present in solutions free 

 from other metals. The fourth chapter treats of the 

 separation and determination of the metals in a mixture ; 

 while the last is devoted to a few technical applications, 

 such as the analysis of industrial copper, of bronzes, and 

 of brass. 



The practical portion of the book is clearly written ; 

 but on account of the lack of details in the case of a 

 considerable number of the analyses, the book can 

 scarcely be recommended to electro-chemical students for 

 use in the laboratory. 



Essaisdes HuilesEssentielles. By Henri Labbd, Ing^nieur- 



Chimiste. Pp. 187. (Paris : Masson et Cie.) 

 This neat little volume, which forms part of the 

 " Encyclopedie scientifique des Aide-M^moire," published 

 under the direction of M. Leaute, is mtended as an intro- 

 duction to the analysis of essential oils, substances which, 

 according to the author, are very liable to adulteration. 



The directions given for analysis are too general and 

 brief to be of real utility to the practical analyst, but the 

 properties of the pure products, compiled from Schimmel 

 and Co.'s publications and from other trustworthy sources, 

 are carefully tabulated, so that the book will at least be 

 serviceable for purposes of reference. 



Chemistry for Organised Schools of Science. By S. 

 Parrish, B.Sc, A.R.C.S. With Introduction by Dr. 

 D. Forsyth. Pp. xiv -f- 262. (London : Macmillan 

 and Co., Ltd., 1899.) 



The course of experimental work described in this 

 volume is designed for students in Schools of Science of 

 the Department of Science and Art during their first two 

 years of study. It is the outcome of experience, and 

 represents the work which pupils from thirteen to fifteen 

 years of age can do and understand. Following the re- 

 formed plan of teaching chemistry, the course begins 

 with simple chemical manipulations, weighing, solutions, 

 distillation, the preparation of common gases, com- 

 position of water and air, formation of salts, carbon and 

 its oxides and a few organic compounds. In the second 

 year's course easy quantitative experiments are given, 

 and attention is paid to the laws of chemical combination, 

 symbols, formula;, &c. The halogens, sulphur and its 

 compounds, the estimation of volume, are among other 

 subjects dealt with. The test-tubing exercises, which 

 once formed the chief part of the work of the student of 

 elementary chemistry, are omitted altogether ; and in 

 their place we have a rationally constructed course of 

 work, in which the intimate relation between chemistry 



