^56o 



NATURE 



[October 13, i8q2 



oxygen." More objectionable still are occasional in- 

 stances of bogus reasoning, the most striking example 

 being an erroneous proof of the conservation of mass. 

 On three different occasions the indestructibility of matter 

 is stated to be a consequence of the law of definite pro- 

 portions. Almost equally bewildering is an attempt to 

 show that " a molecule occupies two volumes," an attempt 

 which even when correctly carried out might well be ex- 

 cluded from a book which professes to discourage any- 

 thing akin to cramming. No advance is made in 

 familiarizing the learner with accurate conceptions of 

 atom and molecule ; indeed the need for the latter con- 

 ception in chemical philosophy is quite overlooked. 



Throughout the book the author's mode of expressing 

 himself is frequently not the happiest. To say that 

 " air allows all bodies that will to take fire in it," or that 

 *' chlorine does not combine with an excess of hydrogen " 

 is harmless enough perhaps. On the other hand to talk 

 of the " properties of a mixture " being the " sum of the 

 properties of its constituents," or of the gas being kept 

 dissolved in a bottle of soda water " by the pressure of 

 the cork," or to say that " water has weight and exerts 

 pressure " cannot but be puzzling to the intelligent reader. 

 To prepare a thoroughly good introduction, of the most 

 elementary kind, to the study of chemistry, is a work of 

 considerable difficulty, indeed it is one which few of our 

 leading chemists seem desirous of undertaking. Enough 

 we think has been quoted from the book under notice to 

 show that the author has by far underrated the difficulty 

 of this task. J. W. R. 



LIFE AND DBA TH. 

 Essai sur la Vie et la Mort. Par Armand Sabatier. 



(Paris : Bab^ et Cie.) 

 pROF. SABATIER' S "Essai sur la Vie et la Mort" 

 forms the fourth volume of the " Bibliotheque Evolu- 

 tioniste," a series of books published under the direction 

 of M. de Varigny, with the view of expounding in a 

 strictly scientific manner the different principles and the 

 diverse applications of thejtheory of Evolution. The 

 series most appropriately begins with a translation of 

 Wallace's " Darwinism," and it is gratifying to our na- 

 tional pride to find that the two other works which have 

 as yet appeared in the series, Ball's " Treatise on Use 

 and Disuse," and Geddes' and Thomson's " Evolution of 

 Sex," as well as the two others announced as in the press, 

 are all by British authors. 



The present essay, which extends over 280 pp., is the 

 outcome of a series of lectures delivered at the University 

 of Montpellier. It is written in a clear, simple style, 

 devoid for the most part of all technicalities which appeal 

 only to the specialist. The problems of life and 

 death are dealt with from an exclusively biological 

 point of view, and questions of morality and theology are 

 hardly touched upon. It is difficult to do justice to the 

 views expounded in the book in the short space at our 

 disposal, but an attempt may be made to give a short 

 account of its contents. The first part deals with life : 

 the properties of living matter are considered in great 

 detail, and Prof. Sabatier endeavours to show that the 

 attributes of life are found to some extent, at any rate, in 

 NO. 1 198, VOL. 46] 



dead matter. According to his views " la mati&re brute 

 est vivante aussi," but the manifestations are slow and 

 dull. To the Professor's mind living matter and dead 

 matter are not absolutely distinct : between the two states 

 of matter there is only a difference of degree and not of 

 kind. " I^ vie done est partout, dans la matiere dite 

 inanimde comme dans la matiere vivante." The various 

 features in which dead matter behaves like living, are 

 considered at great length ; but, curiously enough, no 

 mention is made of Biitschli's remarkable experiments on 

 artificial amcebas, recently described in the "Quarterly 

 Journal of Microscopical Science." 



This view being accepted, death in the ordinary sense 

 of the word, naturally cannot exist, and the phenomenon 

 which we usually call death becomes but another form of 

 life—" la vie intense " simply passes into the state of " la 

 vie lente." Immortality, according to our author, con- 

 sists in the indefinite continuity of life (" la vie intense ") 

 without arrest or interruption. Like Weismann, he 

 maintains that the negation or the contrary of such 

 immortality involves the presence of a dead body or 

 corpse. Weismann holds that ciliated infusoria are 

 immortal if kept under favourable conditions, these con- 

 ditions, of course, including frequent opportunities of 

 conjugating. Sabatier considers that such infusoria are 

 only potentially immortal, and that the act of conjuga- 

 tion converts this potentiality into a real immortality. 

 In his opinion the primitive protoplasm was immortal, 

 and the habit of dying has been acquired by the higher 

 organisms in response to two stimuli, one internal and 

 one outside themselves. The internal cause of death is 

 associated with a tendency innate in the living being to 

 improve its position in the world, in response to which it 

 has become more specialized, and developed new organs 

 and powers. This specialization has borne with it the 

 seeds of death. The external cause is the surrounding 

 world, which constantly stimulates and promotes the 

 organism to new efforts, and in the struggle for the 

 mastery death is brought about. 



Although we fail to see that Prof. Sabatier has thrown 

 any new light upon the problems he attempts to solve, 

 and although the explanations he advances seem to us 

 inadequate, his book is a useful one, inasmuch as he 

 gives us a careful summary of the numerous views ad- 

 vanced by various writers in the last twenty-five years, 

 on the subject of life and death, and criticises with con- 

 siderable ability the theories of Weismann, Goette, 

 Minot, &c. In fact, his destructive powers seem greater 

 than his constructive. A. E. S. 



OUR BOOK SHELF. 



Contagious Foot Rot in Sheep. By Prof. G. T. Brown, 

 C.B., 16 pp., 8 illustrations, (John Murray). 



THIS pamphlet is a reprint from the second part of 

 the current volume of the Royal Agricultural 

 Society's Journal. A few additional remarks on the pre- 

 vention of foot rot have been added, and if the in- 

 structions given were fully carried out, the disease would 

 soon cease to be troublesome. The preventive suggestions 

 are (i) separation from the rest of the flock for one month 

 of all animals newly purchased; and (2) isolation of all 

 animals affected. 

 In discussing the treatment of the disease. Prof. Brown 



