June, 1905.] 



KNOWLEDGE & SCIENTIFIC NEWS. 



135 



REVIEWS OF BOOKS. 



The Principles of Heredity. G. Archdall Reid, M.B., 

 F.R.S.E. (Chapman and Hall, 1905.) This volume is, we 

 are told, addressed to medical men, the evidence relied 

 upon being largely drawn from medical sources. Never- 

 theless the author has so consistently avoided the use of 

 technical language, and his reasoning is so clear and acute, 

 that it should prove very interesting to the general reader. 



The author commences with a chapter upon the " Theories 

 of Heredity," following on with chapters upon " Theories of 

 Evolution. Use and Disuse, and Spontaneous Variation." In 

 these chapters he reviews the main features of the evolution- 

 ary theory, as accepted by the majority of biologists of the 

 present day. The Bathmic theory and the Lamarchian 

 theories are dismissed as fundamentally opposed to observed 

 facts, there being little or no evidence to justify belief in the 

 inheritance of acquired characters, even in the lower forms of 

 life. The theory that organisms are gradually adjusted to 

 their environment by processes of variation and selection is 

 accepted. 



The effects of use and disuse are dealt with in a lucid and 

 most suggestive manner. Man and the higher animals are 

 described as large superstructures of " acquirements " built 

 upon comparatively slender foundations of inborn characters. 

 The hair, the teeth, the nose, the nails, &c., are wholly inborn 

 characters, and are quite unaffected by use and disuse, but 

 the muscles of the legs and other limbs, the heart, the blood 

 vessels, the lungs, &c., can only reach their proper develop- 

 ment by acquirement, and can only be maintained by the 

 e.xercise necessary for their acquirement. It is thus clear 

 that the modifications resulting from use and disuse are not 

 transmitted to subsequent generations, but only the power of 

 acquiring modifications under similar circumstances. 



Under the title of " Recapitulation " the author endeavours 

 to establish and remodel the old theory that the development 

 of the individual is a blurred recapitulation of the history of 

 the race. This theory, as stated by Mr. Reid, lil<e the many 

 other theories of " Heredity," contains much truth, but not 

 the whole truth. Each theory may form a stepping-stone to 

 some final and completely satisfactorv laws of heredity, but 

 one feels that the pressing need nf the moment is work. The 

 laws governing the inorganic world were established by a host 

 of workers experimenting until a mass of organised knowledge 

 was accumulated which placed those laws beyond dispute. 

 Each new work upon this subject impresses one that students 

 of heredity rely too much upon empirical observation, and 

 upon the work of the practical man in rearing animals 

 and plants. Such sources of knowledge are too incomplete 

 and disconnected to enable us to attain a complete know- 

 ledge of this important subject. 



Under the title of " Biparental Reproduction " we are told 

 that its tendency is to result in regression to the specific 

 mean, and that there is not an iota of evidence to prove that 

 biparental reproduction is connected with variation as a cause 

 and effect. The author appears to disregard the fact that in 

 the words of E. Ray Lancaster • : " Breeders of horses, cattle, 

 and sheep, and dog, pigeon and poultry fanciers, crop growers, 

 nurserymen, tulip maniacs, and the like cross- 

 breed here, and crossbreed there, until the specific potential 

 is broken down and strange and unlocked for variations are 

 born ana grown up irrespective of strange and abnormal sur- 

 roundings. From these congenital variations they select the 

 desired forms, and perpetuate them with perfect assurance 

 and security." A good example of what can be accomplished 

 in this manner by biparental reproduction is the result of 

 some hundred years' work upon the rose. From a compara- 

 tively few wild forms, many thousands of cultivated species 

 and varieties have been produced. Chapters upon " Regres- 

 sion " and the causes of " Spontaneous Variation " conclude 

 this section of the work, and chapters upon the " Evolution 

 against Disease," "Narcotics," ".Automatic and Voluntary 

 Action," " the Mind of Man," Methods of Religious and 

 Scholastic Teaching," and other subjects treated from an evolu- 

 tionary point of view, occupy the remainder of the volume. 



In a work of this character, extending over a wide field 

 of knowledge, one naturally finds statements which invite 



* Nature, Nivember 29, 1S94. 



criticism. Mr. Reid may, however, be congratulated upon 

 having contributed a work to the literature of evolution in 

 which he has approached the subject from a new point 

 of view, and which contains much that deserves careful 

 attention. 



The Tutorial Chemistry.— Parts I. and II., by G. H. Bailey, 



D.Sc, &c. Second edition (University Tutorial Press), 3s. 6d. 

 each part. This work, first issued some ten years ago, has 

 already earned a good reputation, but modern progress, with 

 its reforms in the methods of chemical teaching, has demanded 

 that it should be brought up to date. The main features of 

 the work have been retained, but Part I. (non-metals) now 

 contains two distinct sections. Of these, section I. consists of 

 an introductory course based on a series of simple experiments 

 and designed to illustrate the leading laws and principles of 

 the science and to train the student as early as possible in 

 '■ scientific method." Section II. contains a systematic treat- 

 ment of the non-metals illustrated by numerous instructive 

 and typical experiments ; the proofs of composition and con- 

 stitution form a special feature, and in the case of each 

 important substance some account is given of its history and 

 the purpose for which it is employed. Part II. (metals) also 

 consists of two sections, section I. being anaccount of physical 

 chemistry, which has been here brought completely up to date. 

 Section II. is a full account of the metals; the chemistry of 

 radium, electro-chemical methods for extraction of metals, the 

 determination of atomic weights, and many other matters of 

 interest depending upon recent researches and discoveries 

 have received special attention. The book, as it now stands, 

 gives a complete account of chemistry as usually studied for 

 University final degree examinations. For intermediate science 

 students of London University who wish to keep closely to its 

 syllabus, asterisks have been placed to those paragraphs 

 which do not fall strictly within the scope of the examination. 

 There are one or two instances in which one might have ex- 

 pected the book to be rather more up-to-date. For instance, 

 very little is said about calcium or the new method of obtain- 

 ing it. The new alloy " Invar " is not referred to b\' name, nor 

 can we find any allusion to the recently discovered magnetic 

 alloy of copper and manganese. 



Modern Industrial Progress, by Charles H. Cochrane (Lip- 

 pincott Co.), price los. Gd., is really a very fascinating book. 

 It is not by any means a scientifically accurate account of this 

 exhaustive subject, but the story is well told, the illustrations 

 profuse and alluring (if not always very correct), and the 

 matter abundant and of great variety. We are told of elec- 

 tric generators and .X-rays, of electric trains and " converters," 

 of wireless telegraphy, of steel manufacture and the treatment 

 of ores, of aerial navigation and kites. Evolutions in vehicles 

 and roadways, in ships, and in tools of destruction are 

 described, as are canals and tunnels, timber gttting and work- 

 ing, mining, food, and water. Engineering enterprises of all 

 sorts are gone into, and, in fact, to give even a list of the 

 matters which are here attractively described would fill 

 more space than we can devote to it. What is here tcld must 

 be taken with — well, a milligramme — of salt, but this minute 

 saline admixture does not detract from its forming a very 

 readable and even instructive book. 



N-Rays : A collection of Papers communicated to the 

 Academy of Sciences, by R. Blondlot ; translated by J. Garcin 

 (Longmans, Green and Co.; price 3s. 6d. net). — Professor 

 Blondlot has experienced in his efforts to make known the N- 

 rays the truth of the maxim that the way of the scientific dis- 

 coverer is hard ; and though other theorists before him have 

 had to battle quite as hard for their theories, it is doubtful 

 whether the scepticism expressed about the reality of the 

 phenomena he has observed has ever been quite of the same 

 kind. One might say that the sceptics, except in France, still 

 outnumbered the disciples, and that the proselytes were few 

 in number. But in a case of this kind one piece of affirmative 

 testimony must outweigh a great deal of negative evidence, 

 and M. Blondlot's critics^are divided among themselves, some 

 maintaining that the alterations which the hypothetical N- 

 rays produce in the luminosity of a testing screen are due to 

 heat, while others say that the alterations do not exist at all. 

 In the domain of affirmative testimony there has lately 

 been added evidence of the greatest importance from Pro- 

 fessor Hackett, of Dublin University, who has attained such 

 definite results that he is able to discern, through the aid of 



