98 



NA TURE 



[May 29, 1890 



others deserves the attention of the medical profession, 

 and Dr. Wood's paper is of the greatest interest in this 

 connection. 



Of the gynaecological articles, undoubtedly the most im- 

 portant is that by Drs. Barbour and Webster, upon the 

 " Anatomy of Advanced Pregnancy and of Labour." The 

 opportunities afforded to these observers have fallen to 

 no others either abroad or in this country, and they have 

 employed them to the full. The illustrations to their 

 paper, as indeed throughout the Reports, are excellent. 



J. G. Adami. 



ABSTRACT MECHANICS. 

 Le(^ons Synthetiques de Mecanique generate , servant d' In- 

 troduction au Cours de Mkanique Physique de la 

 Faculte des Sciences de Paris. Par M. J. Boussinesq, 

 Membra de I'lnstitut. Publiees par les soins de MM. 

 Legay et Vigneron, Eleves de la Faculte. (Paris : 

 Gauthier-Villars, 1889.) 



THE following Table des Matieres will serve to show 

 the scope of this treatise : — 



!•= Legon. But de la Mecanique physique. Notions 

 cindmatiques indispensables. 



2^ Legon. Les deux principes fondamentaux de la 

 Mdcanique. 



3*= Le(;on. Forme des Equations du mouvement ; ce 

 qu'on entend en Mecanique par force, forces motrices, 

 actions mutuelles, &c. Pesanteur. 



4*= Legon. Energie potentielle interne. Action mold- 

 culaire. 



5^ Legon. Principes de la conservation des quantitds 

 de mouvement et de leurs moments, pour un systeme 

 materiel independant ou sans relations exterieures. 



6^ Legon. Principes des quantitds de mouvement et 

 des moments pour un systeme partiel ; de leur appli- 

 cation h, la formation des Equations de mouvement des 

 corps. 



7^ Legon. Idees generales sur les pressions. 



8'= Legon. Raisons physiologiques et psychologiques 

 des denominations de forces, actions, tensions, &c., em- 

 ployees en Mecanique, Forces d'inertie et centrifuges. 



9^ Legon. Principe des forces vives pour un systeme 

 partiel. Travail des forces. Energie interne, 



10"= Legon. Suite de I'^tude des forces vives et du 

 travail ; flux de chaleur ; loi fondamentale de la 

 Thermodynamique. 



11= Legon. Application du principe des forces vives 

 aux mouvements visibles ou moyens locaux ; roles qu'y 

 prennent le travail de deformation des pressions exercdes 

 sur les particules matdrielles et I'energie potentielle de 

 pesanteur ; &c. 



Such is the interesting syllabus of the subjects lectured 

 upon by the author ; and it is melancholy to think what 

 we have lost in the treatment and illustration of such a 

 programme at the hands of Maxwell, as a sequel and 

 amplification of his inimitable little " Matter and Motion." 



But when we open these pages we find a great contrast 

 before us, and a great disappointment. Hardly anything 

 more is to be found here than the elementary banalites 

 of pure mathematics, in the shape of the explanation of 

 co-ordinates and their differential coefficients as employed 

 NO. 1074, VOL. 42] 



in representing the motion of a particle, and thence of 

 a rigid body considered as an aggregation of particles. 

 There is no interesting illustration or application or even- 

 diagram ; merely a sequence of simple formulas of pure 

 mathematics, interspersed with some metaphysical specu- 

 lation ; it is the purest of mathematics even by the side 

 of Lagrange's " Mecanique Analytique " ; we are given 

 plenty of Mathematics, but very little Mechanics. The 

 words of the preface to the " Lectures in Natural Philo- 

 sophy in the University of Oxford," A.D. 1700, by John 

 Keill, Savilian Professor of Astronomy, appear to be 

 applicable even at the present day : " Although now- 

 adays the mechanical Philosophy is in great Repute, and 

 in this Age has met with many who cultivate it, yet in 

 most of the Writings of the Philosophers, there is scarce J 

 anything mechanical to be found besides the Name. \ 

 Instead whereof, the Philosophers substitute the Figures, 

 Ways, Pores, and Interstices of Corpuscules, which they 

 never saw ; " &c. 



These " Legons " are the first of a course of Physical 

 Mechanics to be delivered at the Sorbonne, with the 

 intention of solving the Universe ; but so far the author 

 does not appear in touch with the physical questions, and 

 he derives his mechanical notions from words in pre- 

 ference to facts. No doubt this is an excellent discipline 

 for some minds, but to the applied mathematician it is 

 devoid of all flavour. 



The note to p. 34 we have found the most interesting 

 passage in the book, pointing out that g varies with the 

 position of the sun and moon, but that the variation 

 would be imperceptible but for the tides. 



The French have the advantage of possessing the two 

 \soxAs poids and pesanteur j much of our own dynamical 

 confusion would be cleared up if we had a separate word 

 equivalent to pesa7tteur, something like gravity, or gravi- 

 tation, as proposed by Thomson. 



The word force vive for mv"^ is still allowed to appear 

 in these pages, in spite of all the recent efforts of Thomson 

 and Tait, Maxwell and recent writers to banish it to 

 oblivion ; this is carrying reverence for Lagrange too far 

 for modern progress. 



Maxwell's "Matter and Motion" practically covers the 

 same ground as these " Legons," and the two books com- 

 pared would offer the best idea of the difference between 

 the teaching of abstract Mechanics in this country and 

 in France. A. G. G. 



OUR BOOK SHELF. 

 A Manual of Anatomy for Senior Students. By Edmun d 



Owen, M.B., F.R.C.S, (London : Longmans, Green, 



and Co., 1890.) 

 This manual has been written from a point of view differ- 

 ent from that usually adopted in anatomical text-books. 

 Instead of giving a detailed systematic or topographical 

 description of the whole of the organs or parts of the 

 body, the author has selected those regions or structures 

 which have a special reference to medical and surgical 

 practice, and he has described them as fully as is 

 necessary to bring out the points which have to be con- 

 sidered and attended to by the practitioner. In making 

 his selection, he has not limited himself to a description of 

 those parts or arrangements which are characteristic of 

 adult structure, but he has incorporated in his book an 

 account of such developmental anomalies as are sometimes 



