294 



NATURE 



[January 25, 1900 



Camerarius' method was thoroughly Darwinian. His 

 conclusions were based entirely on most careful personal 

 observations ; and all objections to his explanations were 

 impartially noted and carefully considered. It was largely 

 from the phenomena exhibited by unisexual, and espe- 

 cially by dioecious, plants that Camerarius drew the con- 

 clusion admirably summed up in his own words 

 (Garnsey's translation) : " In the vegetable kingdom no 

 production of seeds , . . takes place unless the anthers 

 have prepared beforehand the young plant contained in 

 the seed. It appears, therefore, justifiable to give these 

 'apices 'a nobler name, and to ascribe to them the signi- 

 ficance of male sexual organs, since they are the recep- 

 tacles in which the seed itself, that is, the powder which 

 is the most subtle part of the plant, is secreted and col- 

 lected, to be afterwards supplied from them. It is equally 

 evident that the ovary with its style represents the female 

 sexual organ of the plant." 



The thanks of all botanists are due to the publishers 

 and to Prof. Mobius, who has prepared the translation, 

 for this somewhat tardy tribute to the work of a great 

 investigator. But few of his contemporaries recognised 

 its merits ; our own fellow-countryman, Ray, perhaps, 

 more than any other. A. W. B. 



fournals and Papers of Chauncy Maples, D.D., F.R.G.S., 

 late Bishop of Ltkoma, Lake Nyasa. Edited by 

 Ellen Maples, Pp. 278. (London : Longmans and 

 Co., 1899.; 

 The presence of an attractive and educated personality 

 for some twenty years in equatorial savage Africa is 

 explained by the fact that Chauncy Maples was an Oxford 

 member of the Universities' Mission to Central Africa. 

 The first sixty pages contain the journal of his journey 

 through the Meto country, an abstract of which was 

 given before the Royal Geographical Society in 1882. 

 The last paper is the unfinished one of a series in the 

 Nyasa News, the first paper printed on the lake, and 

 started by him in 1893. It ends with pathetic abrupt- 

 ness by an unanswered question : he was drowned in 

 the lake as he was writing it. The papers form a sequel 

 to the " Life," which has already been noticed in 

 Nature ; they manifest a sincere, human and kindly per- 

 ception of the aims of scientific investigation. There is 

 much chatty natural history throughout these papers. 

 One of them compares Anyanja with Melanesian as 

 depicted in Dr. Codrington's "Studies." But perhaps 

 the most valuable contribution is the paper read in 1891 

 before the Oxford Graduates' Missionary Association 

 on the power of the conscience, the sense of the moral 

 law, and the idea of God amongst certain tribes in East 

 Africa. Anthropologists will, in fact, find the first-hand 

 impressions of a cultured English gentleman after years 

 of residence. }. F. H. 



Lemons de Chimie Physique. Par J. H. van't Hoff. 

 Ouvrage traduit de I'allemand par M. Corvisy. 

 Deuxi?me partie : La Statique Chimique. Pp. 162. 

 (Paris : Hermann, 1899.) 



We have now before us a French translation of the 

 second part of van 't Hoflfs admirable lectures on 

 physical and theoretical chemistry. Attention was drawn 

 in the notice of the first part (Nature, vol. lix. p. 458, 

 1899) to the somewhat unusual division of the subject. 

 There, under the title of chemical dynamics, equilibrium 

 and velocity of reaction were dealt with on the basis of 

 thermodynamics and the law of mass action ; here, 

 under the title of chemical statics, we have a methodical 

 and systematic treatment of molecular chemistry. In 

 Part I. mathematical methods were of necessity adopted; 

 n Part II. the methods are more purely chemical, and 

 will appeal in especial to the organic chemist. 



After a short review of the nature of the atomic and 

 molecular theories, the author proceeds to discuss 

 NO. 1578, VOL. 61] 



molecular weight and polymerism in a section which 

 occupies half the present volume. Avogadro's law 

 and the molecular weights of gases naturally receive 

 first attention, and are briefly disposed of' Then, 

 at much greater length, come the methods for the 

 determination of molecular weights in solution, the 

 classification being in accordance with the thermo- 

 dynamic cycles involved in their deduction from the 

 gas-laws for dilute solutions. Molecular complexity and 

 the anomalies encountered with isomorphous mixtures 

 and electrolytic solutions are next discussed, the section 

 concluding with an account of the work done on solid 

 solutions. The author clearly discriminates between 

 crystalline and amorphous solutions, and it is interesting 

 in this connection to find that he is of opinion that 

 palladium-hydrogen probably contains the hydrogen in 

 the state of single atoms, and that the retention of dyes 

 by fibres is not, strictly speaking, a case of solid solution, 

 but of surface action, like the absorption of various 

 substances by charcoal. 



The second section of the book is on molecular 

 structure, and includes subjects of such general chemical 

 interest as the determination of constitution and con- 

 figuration, isomerism, tautomerism and racemism. As 

 one might expect from the chief founder of stereo- 

 chemistry, the treatment of this section is masterly, both 

 in its brevity and in its clearness. 



The third and concluding section deals with molecular 

 grouping and polymorphism. In it are discussed the 

 laws regulating the transformation of polymorphous 

 substances, the theories of crystallographic structure, 

 and the orientation of molecules in the crystal. 



To those who teach and to those who study advanced 

 chemistry the book is indispensable. J. W. 



Gli Agrunii. By Prof. Antonio Aloi. Pp. xi -I- 238. 



(Milano : Ulrico Hoepli, 1900.) 

 This book, which is one of a series of manuals, deals 

 with the cultivation of oranges, lemons, and other species 

 of the genus Citrus. 



Among the subjects treated of are the soil and climate 

 suitable to the growth of these plants, manuring, graft- 

 ing, spacing of the trees, pruning, irrigation, parasites, 

 and maladies. One may mention as deserving special 

 notice the tables given to elucidate the scientific treat- 

 ment of manuring, which are calculated from chemical 

 analyses of fruit, leaves, &c., combined with the com- 

 puted production of the latter per plant. With regard 

 to maladies, dififerent remedies, which have been sug- 

 gested and tried, are described. The concluding chapter 

 contains calculations as to the expenses and profits con- 

 nected with the cultivation of the plants in question. 

 The book is small, nicely got-up, and contains five 

 coloured plates illustrating dififerent diseases, and twenty- 

 two wood-cuts. It should be very useful to those con- 

 cerned in the cultivation of oranges and other plants ; 

 many points in it, moreover, are of interest to the general 

 botanist. 



Star-Land. By Sir Robert S. Ball, F.R.S. New and 

 revised edition. Pp. viii -f 388. (London : Cassell 

 and Co., Ltd., 1899.) 

 The new edition of this popular work on astronomy, 

 based on lectures addressed to a juvenile audience, calls 

 for little remark. A few additional illustrations have 

 been introduced, but we are astonished to find that some 

 of the original diagrams have not been amended. Fig. 

 17, for example, shows a large sun-spot far outside the 

 sun-spot zone ; and Fig. 23 shows the altitude of the sun 

 at noon on the shortest day much too great in comparison 

 with the position indicated for the longest day. If the 

 author's name were unknown, diagrams like these would 

 certainly suggest a want of personal acquaintance with 

 astronomical phenomena. 



