76 



NATURE 



[May 28, 1896 



in-formed that many of the sensations which he refers to 

 taste are in reality referable to smell, and it is on account 

 of the same ignorance, that the child thinks he is treated 

 irrationally when his nose is held while his castor-oil is 

 being administered to him. 



A few facts of this sort will be all that an ordinary 

 reader will carry away from a perusal of this book. The 

 book will be really valuable only to the physiologist who, 

 like Dr. Zwaardemaker, is willing to devote himself to 

 the study of the physiology of smell. 



Computation Rules and Lngarithins. By Prof Silas W. 



Holman. Pp. .\lv + 73. (New York and London : 



Macmillan and Co., 1896.) 

 The first portion of this book treats of the way to use 

 logarithms so as to apply no more figures than necessary ; 

 the author pointing out that probably one half of the time 

 expended in computations is wasted through the use of 

 excessive number of places of figures, and through the 

 failure to employ logarithms. With this in view, rules 

 are given showing what place tables to employ, and also 

 how many figures to retain to obtain an accuracy of any 

 desired percentage. 



That such rules are of high importance may be seen 

 from the fact that the use of five place tables when four 

 would suffice nearly doubles the labour ; using six place 

 instead of four nearly trebles it, thus wasting a hundred 

 and two hundred per cent, respectively of the necessary 

 amount of work, and probably a greater proportion of 

 time. 



Besides these rules and the usual explanation to the 

 collection of mathematical tables, there is a short treat- 

 ment on " Notation by Powers of Ten," which, as the 

 author sees, is a method that if taught with elementary 

 arithmetic, it would enormously facilitate the teach- 

 ing of logarithms ; but his " Symmetrical Grouping of 

 Figures " about the unit's place is a departure likely 

 to be received with some degree of conservatism. There 

 is a useful paragraph on the " Habit in Reading off 

 Numbers or Logarithms," which consists in emphasising 

 and grouping the figures in a certain habitual way. The 

 latter part of the book is taken up by a collection of 

 mathematical tables, e.g. logarithms, antilogarithms and 

 cologarithms to four places, logarithms to five places, 

 logarithms of the trigonometrical functions, slide wire 

 ratios to four places, &c. The decimal point, usually 

 omitted, has been retained in the tables for facilitating in 

 reading off. 



Rema7-kablc Eclipses. By W. T. Lynn. Pp. 52. (London : 



Edward Stanford, 1896.) 

 This " sketch of the most interesting circumstances con- 

 nected with the observation of solar and lunar eclipses, 

 both in ancient and modern time," appears at a very 

 appropriate time, since in a little more than two months 

 the general public will be mildly interested in a total 

 eclipse of the sun, for the observation of which in Norway, 

 Japan, and elsewhere, many astronomers are making pre- 

 parations. Mr. Lynn has contrived to compress a mar- 

 vellous amount of very readable information in his slender 

 little volume, and as a condensed statement of the history 

 of eclipse observations his essay is admirable. The book 

 is uniform with " Remarkable Comets," and it deserves 

 the same successful career as its forerunner. 



The Old Light and the New. By Wm. Ackroyd, F.I.C. 



Pp. 102. Illustrated. (London : Chapman and Hall, 



Ltd., 1896.) 

 We very much question the wisdom of placing this 

 book upon the market. The information on researches 

 with Rontgen rays is very sketchy, while a large portion 

 of the book, dealing with theories of the natural colours 

 of bodies, is nothing more than padding, and is altogether 

 out of place in a volume of this character. 



NO. 1387, VOL. 54] 



LETTERS TO THE EDITOR. 



[The Editor does not hold himself responsible for opinions ex- 

 pressed by his correspondents. Neither can he undertake 

 to return, or to correspond with the writers of, rejected 

 manuscripts intended for this or any other part of NArUKE. 

 No notice is taken of anonymous connnunitatioiis.'] 



A Curious Idiosyncrasy. 



A STROiSGLY marked idiosyncrasy has lately come to my 

 notice, which should be recorded. A lady of my acquaintance 

 was walking with a relative, Colonel M., when the wife of a 

 tenant addressed her, and described how the hand of her own 

 child had been pinched in a door. Overhearing her story, 

 Colonel M. became quite unwell, so much so as to lead to par- 

 ticular inquiry, which resulted in showing that allusions to any 

 accidents of that kind aftected him at once in a very perceptible 

 way. Finally, at the request of the lady, he wrote an account 

 of his peculiarity, which she forwarded to me. Thereupon I 

 corresponded with Colonel M., who slightly revised what he had 

 written, and sanctioned its publication. It is as follows : — 



" From my earliest remembrance, and still up to now, any 

 sight of an injured nail in any person, even if a total stranger, 

 or any injury, however slight, to one of my own nails, causes 

 me to break into a deadly cold perspiration, with feeling of sick 

 faintness. But still further ; if I chance to hear any one else 

 narrating in casual conversation any injury of this particular sort 

 to themselves or others, it brings on me exactly the same feeling 

 I have described above. So much is this the case, that many 

 years ago, when I was in the prime of life, at a large dinner 

 party, when one of the guests near me persistently chanced to 

 goon talking minutely of some such little accidental injury that 

 had befallen him, I turned very faint, tried all I knew to shake 

 it off, but could not, and presently slid right under the table quite 

 unconscious for the moment. This is the more singular because 

 on no other point am I in the least squeamish. In old days I 

 have seen soldiers flogged before breakfast without its affecting 

 me, though some of the rank and file would be very much upset, 

 and in cases of death, illness, or wounds, I have never ex- 

 perienced, as an onlooker, the sensations I have alluded to 

 above." 



I may mention that the mother of Colonel M. had pinched her 

 own finger-nail badly shortly before his birth, and, as is not un- 

 common in coincidences of that kind, she believed her accident 

 to have been the cause of her son's peculiarity. He writes 

 to me : — 



" Asa boy I was conscious of this repugnance of mine, but 

 was ashamed of it, and never used to mention it to any one. 

 When I became a young man I one day mentioned it privately 

 to my mother, who it appeared had already noticed it in me as 

 a child. She then told me the incident about her own finger, 

 and she and I being both utterly unscientific persons, assumed 

 then and there that my squeamish feelings about injuries to finger- 

 tips must be connected with her little accident." 



In reply to further questions, I learn that the injury to the 

 mother, however painful at the time, was not so severe as to 

 leave a permanent mark. Also, that no analogous peculiarity 

 is known to exist among the near relations of Colonel M., of 

 whom he specifies his father, brother, three sisters, nephews and 

 nieces. He has no children. 



This anecdote proves, so far as the evidence goes, that a very 

 peculiar idiosyncrasy may spring suddenly into full existence, and 

 need not develop gradually through small ancestral variations 

 in the same direction. It is a more astonishing phenomenon 

 than the equally sudden appearance of musical faculty in a 

 single member of a non-musical family, being very special, and 

 so uncommon and worse than useless that its ascription to rever- 

 sion, in the common sense of the word, would be absurd. That 

 is to say, it would be silly to suppose a sickly horror of wounded 

 finger-nails or claws to have been so advantageous to ancient 

 man or to his brute progenitors, as to have formerly become a 

 racial characteristic through natural selection, and though it fell 

 into disuse under changed conditions and apparently disappeared, 

 it was not utterly lost, the present case showing a sudden rever- 

 sion to ancestral traits. Such an argument would be nonsense. 

 But though this particular characteristic is of negative utility, its 

 existence is a fresh evidence of the enormously wide range of 

 possibilities in the further evolution of human faculty. 



Fk.\.ncis Galton. 



