July 2, 1900.] 



KNOWLEDGE 



157 



lives and irork of tlie pioneers of modern Italy, and become familiar 

 with such commamlini; personalities as those of Charles Albert of 

 Cariiinan, Camille Cavoiir, and many others, of whom the avera>;o 

 Englishman knows next to nothing. It is a little strange that while 

 so many of our countrjmen .are conversant with Italian art and 

 scenery" and know a great deal about the classic remains which 

 commiind the attention of every scholar, so little interest has hitherto 

 been developed in the constitutional changes and political contro- 

 versies that have taken so great a part in Italian life during the 

 last hundred and fifty years. It is hoped the volume before us vi" 

 do something towards remedying this lack of knowledge. 



" Evolution by Atrophy." By Demoor, Massart, and Vandcr- 

 velde ; translated by Mrs. Chalmers Mitchell. (Kegan Paul.) 

 5s. Much has already been written on the many aspects of 

 evolution, and as science in aU its branches throws otf new slioots 

 as it were, new territory is constantly being appropriated by the 

 evolutionist in his ever-widening sclieme of co ordination. Bio- 

 sociological science is in unstable equilibrium. The naturalist with 

 his limited knowledge of social questions too often erects leaning 

 towers with the centre of gravity outside the base, and the socio- 

 logist, frequently a theorist with little or no training in biology, 

 sometimes builds his pyramids with the apex down.vards. This 

 book, by several authors, aims at presenting a well proportioned 

 view of the structure raised by evolutionists who have prosecuted 

 their investigations into everj- phase of life and the institutions 

 evolved by civilised communities. It is a work full of interest from 

 first to last, but only a skeleton on which new material may be laid 

 and moulded into shape by competent hands. Great inequality 

 obtains in the several chapters ; for example, that on the " Trans- 

 formation of Organs of Animals " is fairly full, while the section 

 on "Atrophy of Institutions" is somewliat meagre. Nevertheless, 

 it is a work of importance, very suitable for the library. 



"Sexual Dimorphism in the Animal Kingdom." By J. T. 

 Cunningham, m.a. xi. and 317 pp. (A. & C. Black.) 12s. net. 

 The phenomena of structure in the animal kingdom may be in- 

 claded, says Mr. Cunningham, under three categories : diversity, 

 polymorphism, and metamorphosis. The present work is devoted es- 

 l)ecially to the consideration of the commonest case of the second of 

 these divisions, and the arguments presented are chiefly concerned 

 with two Sfjecial peculiarities of secondary sexual characters, viz.. 

 (1) these characters do not begin to appear in the individual until it is 

 nearly adult and sexually mature ; (2) they are inherited only by the 

 sex which possesses them. Mr. Cimningham maintains that heredity 

 causes the development of acquired characters for the most part 

 only in that period of life and in that class of individuals in whicti 

 they were originally acquired. In other words, heredity is a 

 tendency in the new individual to pass successively through the 

 same stages of growth as its parent. The theory of evolution 

 put forward, which the author claims as new and original, is stated 

 as follows : " that the direct effects of regularly recurrent stimula- 

 tions are sooner or later developed by heredity, but only in asso- 

 ciation with the physiological conditions under which they were 

 originally produced." In opposition to Weismann, the question of 

 how the inheritance of acquired characters can be produced is 

 not discussed ; in the author's words, " it is a fact that the modi- 

 fications with which I have to deal are hereditary, and my object 

 is to produce inductive evidence that they were determined by 

 special stimulations." After defining his position and setting fort'i 

 the explanation he has to offer, Mr. Cimningham reviews the facts 

 which have been observed in the chief divisions of the animal 

 kingdom, the successive chapters being concerned with Mammals. 

 Birds, Reptiles and Amphibia, Fishes, Insects, and lower sub 

 kingdoms. It is hardly our province to refer in detail to so highly- 

 specialised a piece of work as that contained in this volume. More- 

 over, there is, after all, only a comparatively small amount of 

 material yet available on which to build theories, and it may we'l 

 happen that the accumulation of further data will lead to a necessit- 

 for a restatement of the case — a contingency fully recognised by th"? 

 author. However this may turn out, Mr. Cimningham's work is 

 one that claims, and will doubtless receive, the serious consideration 

 of biologists. 



" The Structure of the Brain." By Albert Wilson, m.d. (EP-ot 

 Stock.) Illustrated. "This work is a re-issue of a more expensivJ 

 book entitled 'The Brain Machine' issued some time since." Ths 

 dominant note in our author's theme is that we are only machlaes, 

 the victims of fate, yet so complex that there remains much at 

 present unknown. " It is no u.se fighting a fractious, self-wiUe 1 

 child. Its brain-cells want cleaning and repairing." " After meals 

 we are sleepy, because the blood has left the brain for the abdom;n." 

 " Our optic centres absorb it (experience) as a photograph, which 

 we recall every time we are exposed to that small danger." In this 

 manner Dr. 'Wilson deals with all the ordinary phases of human 

 life, and he is often very happy in liis concise mode of expression. 

 The book is exceedingly interesting, and is sustained throughout by 

 exact scientific knowledge. 



" A Treatise on Crystallography." By W. J. Lewis, m.a. (Univ. 

 Press, Cambridge.) Ciystallography, at the best, is not an attrac- 

 tive study except to those who are well equipped with the elements 

 of geometiy and trigonometry, and who have, moreover, an inor- 

 dinate love for the ungainly nomenclature employed in the classifi- 

 cation of crj-stals. Professor Lewis has imparted a still more chillini' 

 aspect to the subject by his rigid mathematical treatment Ihroii ;h- 

 out, and the book certainly forms a programme of serio\is work 

 Wo observe that the notation for the crystal forms, tlio treatment 

 by stereogripliic projection, and the anharmonic ratio of four tauto 

 zonal faces, with which the lato I'rofe.ssor Miller's name is asso- 

 ciated, have been adopted. Naumann's symbols, so expressive t ■■ 

 the geometrical relations of the various rhombohedra and scal-no- 

 hedra, are emjiloyed. The index is good, containing as it does .so 

 many names which are invaluable .as a means of reference. Par- 

 ticular care has also been bestowed on the numcrims figures, and the 

 student's itower of solving crystallographic problems may receive 

 a great impetus through the prominence given to the methods used 

 in making diagrams. 



"The Strength of Materials." By J. A. Kwing, F.n.s. 

 (Univ. Press, Cambridge.) Illustrated. Professor Kwing's book is 

 remarkable cliieMy for conciseness. He knows how to express in a 

 nutshell, as it were, what is really necessary Id be said, and does 

 not pad his pages with theories which, like old machinery, have 

 become loose in the joints. Consisting, iis one would expect, very 

 largely of so-called grajihiciil statics, he hanilles the representation 

 of forces by lines and their interiiretation by formulas with ad- 

 mirable skill, .and a student who is fortunate enough to eain 

 possession of this volume will have the " open sesaine " to all those 

 engineering problems immediately concerned with the nature and 

 effects of stresses in the several parts of girders, bridges, beams, 

 and other structures. It is not, however, a beginner's book. To 

 keep pace with the Professor in the present treatise — a lecture-room 

 treatment of the subject accompanied by laboratory and drawing 

 ofhce work — the student must have inured himself to the many 

 difficulties which mathematics, elementary mechanics, and ]ihysics 

 present, before he can hope to tilt with success at the winilmdls 

 here erected. Apparatus as used ab Cambridge is described an,l 

 figured. Tension, torsi(m, crushing, shearing, and the means of 

 obtaining their numerical equiv.ilents — these, and the like, are 

 plastic in the author's hands, and he has put tliem in attractive 

 form for such as have completed the essential preliminaries. 



There are always numbers of photographers who like to use a 

 small apparatus but want to get a good sized picture ; both these 

 desires can be .satisfied in the " Nydia," a neat folding put-into-taa 

 pocket camera which Messrs. Newman & Guardia have recently 

 brought out. 



►-♦-« 



BOOKS RECEIVED. 



Prehistoric Times. 6tli Edition. By tbe Rt. Hon. Lord Avcliiiry. 

 (Williams and Norgatc.) Illustrated. I89. 



Direetory for Science and Art Schools and Classes, S. and A. Z> , 

 1900-1901. (Eyre & Spottiswood(^) (id. 



Hygiene. By R. A. Lyster, li.sc. (Olive.) 2s. 



Electric Batteries. Edited by I'crcivnl Marshall, a.i.m.e. (Daw- 

 barn & Ward.) Illustrated. <id. 



T/ie Proposed National Antarctic Expedition. V>y Wm. S. Bruce. 

 (Pamphlet; reprinted from the Scottish G eoi/raphicil Magazine.) 



Feilden's Magazine. June, 19U(). Is. 



A Little History of South Africa. By Geo. McCall Thcal. 

 (Unwin.) Is. (id. 



In Birdland. By Oliver O. Pike. (Unwin.) Illustrated. Cs. 



Comparative Anatomy of Animals. By Gilbert C. Bourne, m.a. 

 (Bell.) Illustrated. 4s. (jd. 



Chemistry : An Exact Mechanical Phtlosophii. By Fred. G. 

 Edwards. (Chm-cliill.) 38. 6d. 



Annates de V Ohseroatoire National D' Athens. Tonic 11. By 

 Demetrius Eginitis, Directeur. 



Results of Meteorological and Magnetical Ohservations, Stony- 

 hurst College Olservatory, 1899. 



Etching on Metals. — U.seful Arts and Crafts Series. (Dawbarn 

 & Ward.) (id. 



Photography in Colours. By R. Child Bayley. (lliffe.) Is. net. 



Leeds Astronomical Society — Journal and 2Vansactions, 1899. 

 (Wesley. ) 



Liverpool Observatory, Bidslon. — Heport of the Director, 1890. 



Historical and Literary Essays. By Lord Macaulay. (Ward, 

 Lock.) 2s. 



I'he Story of Bird Life. By W. P. Pycriift. (Nownes.) Is. 



Electric Lighting. By A. A. 0. Swinton. (Crosby Lockwood.) 

 Is. (id. 



Local Particulars of the Total Eclipse of the Sun, 1901, May 17-18. 

 (Nautical Almanack Circular, No. 18.) 



