NATURE 



[May 14, 1 89 1 



represented in the forms most approved by climatologists, 

 and discusses with much precision the meaning of different 

 kinds of mean values ; though, indeed, it omits all mention 

 of the geometric mean, the application of which in clima- 

 tology was lately under discussion in the Royal Meteoro- 

 logical Society. But it is, we fear, hardly elementary 

 enough to meet the requirements of beginners and 

 amateurs, especially such as regard a formula of any 

 complexity with something of that distant respect that 

 they accord to holy mysteries ; and on the other hand it 

 aims at nothing beyond the formal and statistical present- 

 ment of facts, and never deviates into the seductive, if 

 sometimes illusive, field of physical causation. It is what 

 its title proclaims it to be, a guide to the working out of 

 meteorological observations for the purposes of climato- 

 logy—the climatology, that is to say, of the temperate 

 zone. For those who work in a more extended 

 field, some of the author's methods and dictates 

 may be found to need modification. His schedule 

 of the usual hours of observation makes no 

 mention of those most frequently observed in the 

 tropics, and his uncompromising condemnation of the 

 use of Lambert's formulae in reducing wind-registers, 

 however justifiable in the case of the variable winds of 

 these latitudes, ignores that of countries where trade- 

 winds or monsoons blow steadily for weeks or months 

 together with but little deviation from the normal quarter, 

 and where the direction undergoes a regular oscillation 

 daily. In working out this daily oscillation at such 

 places, the use of Lambert's formula is not only justified 

 but almost indispensable. 



Within the somewhat narrow limits that Dr. Meyer 

 has prescribed to himself, he has executed his task care- 

 fully and conscientiously, but in this country, at least, 

 his merits are likely to be appreciated by only a sm^ll 

 class ; chiefly, indeed, by that estimable few who find in 

 plodding labour its own sufficient reward. The student 

 who is endowed with some share of scientific imagina- 

 tion, who loves to trace the inner workings of Nature, 

 and sees in diagrams and tabulated statistics only means 

 to this end, will find Dr. Meyer's work a somewhat dry 

 study ; and when he shall have mastered its contents, 

 should he ever be challenged by Arthur Clough's " Ques- 

 tioning Spirit," and asked, 



" What will avail the knowledge thou hast sought?" 



he must answer as he best may from his own mental 

 resources. His author, at least, will not help him to 

 a reply. 



Intensity Coils : how made and how used. By " Dyer." 

 Sixteenth Edition. (London : Perken, Son, and 

 Rayment.) 

 In this book a simple and interesting account is given 

 of galvanic batteries, induced electricity, and the methods 

 of making and using intensity coils, which include numerous 

 experiments that may be described briefly as " popular." 

 In the present edition many other branches of the subject 

 have been touched upon, including electric lighting, elec- 

 tric bells, electric telegraph, electric motors ; and a few 

 words are said on the telephone, microphone, and phono- 

 graph. Although the book is not presented as a scientific 

 treatise, but simply as a guide containing the necessary 

 instructions for making and using the above-named in- 

 struments, yet by its means many may be led to make a 

 more advanced study of the subject, which to-day is of 

 such high importance. 



Getieral Physiology. By Camilo Calleja, M.D. (London: 

 Kegan Paul, Trench, Triibner and Co., Limited, 1890.) 



The author of this book means by the word "phy- 

 siology " " discourse of nature " ; and his intention is to 

 denote by it " the study of positive science in the abstract 

 sense." The scheme he has set before himself is nothing 

 NO. II 24, VOL. 44] 



less than " to comprehend under the fundamental prin- 

 ciple of mechanism— conservation of energy — all the 

 laws and theories concerning nature." In order to show 

 the spirit in which he sets about the accomplishment of 

 his task, it may perhaps be enough to say that he regards 

 the planets as "bodies constituted of organic and in- 

 organic matter," and that to him living organic matter 

 seems " the proximate agent of planetary movements, for 

 which non-living bodies are only the cosmic medium." 

 The sun, we learn, is not "a body in combustion," but 

 "principally a great reflecting mass, which, situated in 

 the focus of the orbits of many planets, reflects their 

 infra-luminous emissions, these producing light by their 

 conglomeration." As for " natural light or daylight," it 

 is " a photothermic radiation produced by transference, 

 not only of the radiating motion of the planets, but also of 

 the motion engendered by solar living beings." If anyone 

 is attracted by writing of this kind, he will find plenty of 

 it in Dr. Calleja's amusing volume. 



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 '^K'^Xiwe.. 

 No notice is taken of anonyvtous communications. 'X 



Co-adaptation. 



It sometimes appears to me that the neo-Darwinians must 

 speak a language of their own, because they are so fond of telling 

 me, in a stereotyped phrase, that, " if words have any meaning," 

 such and such words have expressed some meaning which no 

 ordinary grammatical construction can extract. The present is 

 a good case in point. Prof. Meldola says that he finds " a 

 remarkable discrepancy " between my two previous letters on the 

 above subject, and seeks to reveal it by quoting from the first 

 letter, thus : — 



" ' I do not . . . hold myself responsible for enunciating Mr. 

 Herbert Spencer's argument, which the quotation sets forth, I 

 merely reproduced it from him as an argument which appeared 

 to me valid on the side of "use-inheritance." For not only did 

 Darwin himself invoke the aid of such inheritance in regard to 

 this identical case, . . . ' &c. If words have any meaning, 

 this implies that Dr. Romanes agrees with Darwin in regarding 

 this case as one in which ' use-inheritance' played a part." 



Does it ? When a man says that in his opinion a certain 

 argument in favour of a certain conclusion is valid, is this 

 equivalent to his saying that he accepts the conclusion ? And 

 when he adds, twice over, that he purposely abstains from ex- 

 pressing any opinion of his own with regard to the conclusion, 

 is this equivalent to his saying the precise opposite ? 



The state of the case is simply as follows. Prof. Meldola 

 reproduced Mr. Wallace's argument against Mr. Spencer's 

 defence of "use-inheritance." I wrote to show that this parti- 

 cular argument was invalid ; but that there was another argument 

 on the same side, which,. if adduced, would be valid, supposing 

 that it could be sustained by_ facts. Now, in his reply, Prof. 

 Meldola abandoned the invalid argument, and adopted the one 

 which I had stated. Accordingly I wrote a second time, in 

 order to show that we were then agreed upon this being the 

 only argument which could be logically brought against Mr. 

 Spencer's position. But I again added that I would express no 

 opinion as to whether this argument could be successful in sub- 

 verting Mr. Spencer's position. In point of fact, with regard to 

 this question I have no fully-formed opinion to express. But, 

 unless the neo-Darwinians have eventually become unable to 

 comprehend the attitude of " suspended judgment," one would 

 suppose that they might still appreciate the difference between 

 sifting arguments as good or bad on both sides of a question, 

 and finally deciding with regard to the question itself. 



Christ Church, Oxford, May 8. George J. Romanes. 



I wrote in good faith when in my last brief communication I 

 expressed the intention of allowing the subject to drop, because 

 I considered that the discussion had arrived at a stage when 



