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KNOWLEDGE >S; SCIENTIFIC NEWS. 



[June, 1905. 



his detector screen, the emission of N-rays from a silent 

 tuning fork ; and from Professor Broca, who has examined 

 and distinguished the so-called physiological causes of the 

 rays. We may perhaps sum up the case for the real existence 

 of the rays by a method of questions and answers. Is the 

 change (in the detector screen) due to physical causf s pro- 

 ceeding to the screen? If so, then the physical existence of 

 the N-rays, or of something analogous to them, is established. 

 Is the phenomenon due to changes produced within the eye 

 itself? If so, then physiology must explain all the correlated 

 and complicated phenomena which result — in terms of optica! 

 illusion such as the structure of the eye could produce. 

 Lastly, is the phenomenon due to the mind of the observer? 

 Then, if so, psychology has a task similar to that we have 

 suggested for physiology. If on the contrary all these hypo- 

 theses are false, and there is no appearance of change in the 

 detector screen : that is to say, if, in other words. M. Blond- 

 lot, Professor Charpentier. Professor Hackett, M. Broca, and 

 M. dWrsonval are united to bear false witness, the whole 

 matter seems one for the alienist, for such a tissue of related 

 and corroborative falsehood was never before recorded. We 

 do not hesitate to say. therefore, that we believe the establish- 

 ment of the objective reality of the N-rays to be merely a 

 matter of time and careful experiment. This end will be 

 furthered by the translation before us of the extremely straight- 

 forward, clear, and workmanUke papers which M. Blondlot 

 has communicated to the Paris .-\cademie des Sciences. Here 

 we have collected his own observations, the gradual process 

 of development of his exDeriments. and his candid efforts to 

 meet and reply to criticism. No one can pretend to pass 

 judgment without carefully reading this collected series of 

 papers, to which additional value is given by M. Blondlots' 

 directions for preparing the detector screens. A screen of the 

 kind is furnished as a frontispiece to the work ; and we cannot 

 do better in taking leave of it than to quote M. Blondlot's 

 warning as to the method of observation of N-rays: "It is 

 indispensable in these experiments to avoid all strain on the 

 eye, all effort, whether visual or for eye accommodation, and 

 in no way to try to fix the eye upon the luminous source 

 whose variations in glow one wishes to ascertain. . . In 

 fact, the observer should accustom himself to look at the 

 screen just as a painter would look at a landscape. To attain 

 this requires some practice, and is not an easy task. Some 

 people, in fact, never succeed." 



On False Education, by Frederick Hovenden, F.L.S., F.C.S., 

 F.K.M.S. (Watts; price 3di. — It is perhaps invigorating and 

 salutary occasionally to read attempts to upset and prove 

 illusory one's deeply-imbibed dogmas, or at all events to hear 

 • hem investigated, dissected, and criticised. We have been 

 brought up to believe in mathematics as a subject deserving 

 of our highest respect ; infallible, conclusive, beyond argu- 

 ment. Yet here we are suddenly confronted with an assertion 

 that the whole thing is a mockery and a delusion I Arith- 

 metic exists : two and two still make four. Multiplication 

 is but addition repeated ; two and two and two, that is, two 

 added three times over, make six. But according to this 

 author, 2 X 3 is not at all the same as 3 x 2. Algebra is 

 delusive ; 2rt x 3'' is nonsense ; as well say multiply two apples 

 by three pears ! All this starts one thinking. Where arc we ? 



What Do We Know Concernlni; Electricity? by A. Zimmern, 

 B.Sc. Pp.140. (Methuen and Co., London; is. 6d. net). — 

 This is a delightful elementary account of electrical phenomena 

 intended for readers who may wish to obtain some knowledge 

 of the subject, and who " yet may not have the desire or oppor- 

 tunity to make a thorough study of the subject." The aim of 

 the author will certainly be fulfilled. Simple though the lan- 

 guage is, it seems to be wonderfully accurate; and throughout 

 a style which appro<aches distinction is maintained. The 

 following extracts — which refer to different questions — will 

 illustrate the author's cautious attitude : " The pictorial repre- 

 sentation fof the processes of electrolysis] which scientists 

 now adopt as' a ' working hypothesis ' is this ! " " The modern 

 conception of an ether is an invention due to Huyghens. I 

 use the word invention advisedly because we have no experi- 

 mental evidence for its existence. . . . Yet . . . there 

 is a great and increasing amount of circumstantial evidence 

 for the existence of somf</ii(i(^ of which the ether as we conceive it 

 is the expression suited to our present knowledge." This is excel- 

 lent. We leave the book with regret that we have not referred 

 to"t)ie chapters on the passage of electricity through gases and 

 on radio-activity. 



Bacteriology. — .A. Laboratory Guide in Elementary Bacteri- 

 ology, by William Dodge Frost, Ph.D. Third edition (Mac- 

 millan; price. 73. net). -If one wished to review Dr. Frost's 

 guide to the bacteriological student in the shortest possible 

 number of words, one would say that it was exactly what it 

 professes to bs in its title. It details for the student the exact 

 methods that he will have to follow in the bacteriological 

 laboratory in order to obtain a thorough working knowledge 

 of the science, and to fit him for more extended research. 

 It is arranged with two ideai in view ; the first, and perhaps 

 the more important, to indicate the experiments which a 

 student will have to make and the best way of making them — 

 and in this respect the third edition differs from those which 

 have preceded it by substituting new and improved methods 

 of established examinations of bacterial cultures; and. the 

 second, the best order m which to take these experiments. Thus 

 we proceed from the making of bouillon for cultures to the 

 inoculation of animals and the bacteriological examination 

 for human autopsies. The second subdivisional arrange- 

 ment of Dr. Frost's volume is that which suggests the studv 

 of the various bacteria in groups, the most logical and 

 reasonable method, and the one which is most in keeping 

 with recent tendencies. It is a most valuable and practical 

 manual. 



Sociology. — Sociological Papers, by Francis Galton, E. 

 Westermarck, P. Geddes. E. Durkheim, Harold Mann, 

 V. V. Branford, and James Bryce. (Published for the Socio- 

 logical Society: Macmillan). — The contents of this volume 

 consist principally of the papers read before the Sociological 

 Society last year, and amid a mass of interesting material, 

 the essay by which Dr. Francis Galton strove to establish the 

 new science of " Eugenics " is. perhaps, the most important. 

 Dr. Gallon's idea is that we niav establish the coming race, 

 sound in wind and limb, in mind, and in morals, by selective 

 breeding. It is a hypothesis which we believe to be vitiated 

 by the fact that we do not know what to breed for ; that it 

 is not the fittest that survives, but tiic more fit; and short 

 of exterminating the unfit at birth, a proceeding to which 

 mankind still entertains a sentimental objection, we do not 

 think any method of artificially improving the births of the 

 world would effect much. More entertaining, however, is 

 Dr. Gallon's effort to remedy a noticeable omission in the 

 annals of talent. We have many biographies of great per- 

 sons, but no collection of biographies of gifted families; and 

 since it is probable that brain is as much a heritage as bone 

 or muscle, it is as well for those who wish to improve the 

 race to know how far and in what directions the cleverness 

 of a pareot is transmitted or inherited. Dr. (^lalton's way 

 was to send a letter to Fellows of the Royal Society asking 

 them to give particulars of the noteworthy achievements of 

 their near relatives ; and from the 250 replies received, he 

 arrived at the general conclusion that ability as measured 

 by achievement tended to be a family characteristic in 

 a marked degree. Achievement as a rule was measured 

 by mention in the " Dictionary of National Biography," 

 m the " Encyclopiedia Britannica," and in a lesser degree 

 in " Who's Who ? " but besides families distinguished in 

 this way, there were others whose members were reputed 

 to have a high level of ability. We each of us have on 

 an average ten near male relatives who live long enough to 

 attain distinction if they have it in them — two grandfathers, 

 one father, two uncles, one brother, and four first cousins. 

 Usually distinction is sufficiently rare to make it probable 

 that if one of these ten reaches Dr. fialton's standards of dis- 

 tinction, there is genius in the family ; but Dr. Gallon's statis- 

 tics show that where Fellows of the Royal Society are con- 

 cerned there is the average of no fewer than four distinguished 

 persons in the ten. Some of the family trees are so remark- 

 able as to be worthy of special notice — that of the Darwins, 

 for instance. Charles Darwin was the grandson of lirasmus 

 Darwin, F.R.S., physician, poet, and philosopher ; and of 

 Josiah Wedgwood. F.R.S. He was the son of Robert Darwin, 

 F.R.S., a distinguished physician ; ;ind was the nephew of 

 Charles Darwin, who h.id a career of extraordinary promise. 

 He was, of course, related to other descendants of Josiah 

 Wedgwood, and to the Galton family among them. Of his 

 four sons, Francis, George, and Horace are all I-"ellows of the 

 Royal Society, and Leonard Darwin is a brilliant scientific 

 Engineer officer. Similarly, the Horslcys are related to the 

 Hadens, the Brunels, and the Bramwells. 



