64 



NA TURE 



[Maucii iS, i9og 



for a controversial consideration of the questions at 

 issue. 



This resurrection of obsolete tracts and essays is 

 part of the anti-vivisectionist's stock-in-trade. It 

 enables him to repeat in a book published in 1908 

 the details of experiments made more than half a 

 century ago, and to quote the utterances of a Mante- 

 gazza or a Magendie in a volume dealing with the 

 work of physiologists and bacteriologists to-day. If 

 speaking as avowed vivisectionists we characterised 

 such experiments of Mantegazza, we should admit 

 without hesitation that they were cruel. We have 

 advanced in humanity sincje those days. Even in 

 England, Boyle and his fellow members of the Royal 

 Society approached the subject of experiments on 

 animals^by asphyxiation — without any suspicion that 

 they were employing cruelty in their methods. 



But what have these instances to do with the ques- 

 tion of experiments on animals as practised in English 

 physiological laboratories to-day? A remark by Dr. 

 Leffingwell himself may be commended to the atten- 

 tion of the secretary of the anti-vivisectionist society 

 which publishes his collection of essays. In the first 

 essay. Dr. Leflfingwell says : — 



" In America our physiologists are rather followers 

 of Magendie and Bernard, after the methods in vogue 

 at Paris and Leipzig, than men who are governed 

 by the cautious and sensitive conservatism which 

 generally characterises the physiological teaching of 

 London and Oxford." 



That was written by Dr. Leffingwell in iSSo. 



If the practice of English physiological laboratories 

 was cautious and sensitive twenty-nine years ago, 

 what is the object of re-publishing in England as a 

 contribution to the " Vivisection Controversy " a 

 series of attacks on vivisection as practised in other 

 countries a generation, or more than a generation, 

 ago? What, also, is the object of adding an essay 

 on the " Royal Commission of 1906 " — except to give 

 to the book an appearance of being up to date? The 

 only serious argument in the essay is that " \. C. E." 

 mixture — which is commonly employed on human 

 beings as a very good anaesthetic — ought not to be 

 employed in experiments on animals. This essay is 

 in keeping with the rest of the book in being an 

 appeal, not to facts, but to prejudice, and not to 

 humanity, but to ignorance. E. S. G. 



STRENGTH OF STRUCTURES AND . 

 MATERIALS. 

 (i) The Theory and Design of Structures. By Ewart 

 S. Andrews. Pp. xii-hsSg. (London : Chapman and 

 Hall, Ltd., 1908.) Price <)s. net. 

 (2) The Strength of Materials. By Prof. Arthur 

 Morley. Pp. ix + 487. (London : Longmans, Green 

 and Co., 1908.) Price ys. 6d. net. 

 (i) ' I "'HE soundness of this work as regards the 

 -L theory of the subject is guaranteed by the 

 fact that the methods adopted by the author in 

 dealing with the more difficult problems are based 

 upon lecture notes taken while he was attending the 

 graphics lectures of Prof. Karl Pearson, F!R.S., at 

 University College, London. In the first chapter, 

 NO. i055, VOL. 80] 



which is devoted to the general treatment of the 

 subject of strain, stress, and elasticity, the author 

 deals not only with the case of maximum tensile or 

 compressive and sheer stresses, but also with maxi- 

 mum strain. It is too often forgotten in dealing with 

 complex stresses that the maximum strain does not 

 occur on the same plane as the maximum stress ; it 

 is, therefore, advisable to investigate the question of 

 the maximum stress produced in a body when sub- 

 jected to combined tensile or compressive and shear 

 stress from this point of view. This method of maxi- 

 mum strain, which the author terms the French 

 method, is comparatively little used by engineers in 

 this country, but it is important that designers and 

 students should realise that there is another method 

 of treating the problem other than that ordinarily 

 expounded in English text-books. 



In the section of the book which treats of areas and 

 moments, ingenious graphical methods are described 

 for the determination of areas by means of sum or 

 integral curves, and for the determination of centroids 

 and moments of inertia by similar methods. It is 

 perhaps desirable to point out here that throughout 

 this book there is a large number of examples fully" 

 worked out by both graphical and analytical methods, 

 and in many cases points which are not, or only 

 briefly, touched upon in the general body of the 

 book are fully discussed when solving some of the 

 problems. These worked problems, therefore, will be 

 found of much greater use to the student than is 

 often the case with the examples published in engineer- 

 ing text-books. 



Mr. Andrews, in conjunction with Prof. Karl 

 Pearson, was the author of an original memoir on 

 the theory of stresses in cranes and coupling hooks, 

 and it was only to be expected that the cases where 

 the ordinary assumptions of the beam theory are not 

 allowable would be discussed in this book ; it is to be 

 hoped, therefore, that in future, erroneous theories of 

 the stresses in crane and coupling hooks will disappear 

 from engineering text-books. The correct method of 

 solving the problem certainly involves rather more 

 lengthy calculations, but there is no justification for 

 the sacrifice of accuracy in the calculation of stresses 

 in order to simplify slightly the work of the designer, 

 especially when the results given by the simple formula 

 are seriously incorrect. 



Three chapters are devoted to the deflection of 

 beams, simple, fixed, and continuous, and the distri- 

 bution of shearing stresses in them ; the author has 

 adopted the ordinary analytical method of dealing 

 with the problems, and also a graphical method 

 b ised upon Muhr's theorem that a loaded beam will 

 take up the same shape as an imaginary cable of the 

 same span vt-hich is loaded with the bending moment 

 curve on the beam, and subjected to a horizontal pull 

 equal to the flexural rigidity. In spite of increased 

 attention given to mathematical studies, many en- 

 gineers are still unable, though they have a slight 

 knowledge of the principles of the calculus, to reason 

 in its terms, and such men need graphical methods 

 in order that they shall secure a thorough grip of the 

 problem of beam deflections and stresses. 



