44 



NA TURE 



{May 21, 1874 



The examples given by Mr. Spencer were examples of 

 «HOTtiHi/l'-formed conceptions based on this unconsciously- j 

 formed preconception acquired during childhood and boy- 

 hood. Mr. Spencer gave three instances into which this 

 preconception tacitly enters : one chemical, another relating to 

 the melting of ice, and a third to the process of weighing. The 

 last is the only one into which the relation between force and 

 motion can be supposed to enter. But the consciously-formed 

 conception that double weights will balance double masses, and 

 so on, is not one into which there really enters any relation be- 

 tween force and motion. The notion of weighing is that of the 

 equal forces of equal masses at the ends of equal levers. So long 

 as there is motion, there cannot be equilibrium. The idea of 

 motion is excluded when weighing is complete. 



When Mr. llayward says that Mr. Spencer has taken 

 Newton's "Second Law ol Motion" as an example of uncon- 

 consciously- formed preconceptions, he utterly misapprehends Mr. 

 Spencer's meaning. The " Second Law of Motion" is one of 

 those developed conceptions derived from the orgmiz preconcep- 

 tions above described. 



Mr. Spencer's argument appears to be briefly this :— I. There 

 are numberless experiences unconsciously acquired and un- 

 consciously accumulated during the early life of the individual 

 (In liarmony with the acquisitions of all ancestral individuals) 

 which yield the preconception, long anteceding anything like 

 conscious physical experiments, that physical causes and effects 

 vary together quantitatively. This is gained from all orders of 

 physical experiences, and forms a universal preconception re- 

 specting them, which the physicist orother man of Science brings 

 with him to his experiments. 



2. Mr. Spencer shov/ed in three cases — chemical, physical, and 

 mechanical — that this preconception, so brought, was tacitly in- 

 volved in the conception which the experimenter drew from the 

 results of his experiments. 



3. Having indicated this universal preconception, and illus- 

 trated its presence in these special conceptions, Mr. Spencer 

 goes on to say that it is involved also in the special conception 

 of the relation between force and motion, as formulated in the 

 "Second Law of Motion." He asserts that th^s is simply 

 one case out of the numberless cases in which all these conscious- 

 reasoned conclusions rest upon the unconsciously-formed conclu- 

 sions that precede reasoning. Mr. Spencer alleges that as it has 

 become impossible for a boy to think that by a smaller effort he 

 can jump higher, and for a shopman to think that smaller weights 

 will outbalance greater quantities, and for the physicist to think 

 that he will get increased effects from diminished causes, so it is 

 impossible to think that "alteration of motion " is not " propor- 

 tional to the motive fjrce impressed." And he maintains tliat 

 this is, in fact, a latent implicatiion of unconsciously organised 

 experiences just as much as those which the experimenter neces- 

 sarily postulates. 



I may add that if mathematics included in its range the con- 

 nection between objective phenomena and the answering sub- 

 jective states, this question woula }be one for mathematicians ; 

 but at present it is, as it seems to me, a question pertaining to 

 the psychological basis of inductive logic. James Collier 



Bayswater, May 18 



The Glacial Period 

 I THINK there are but few points in Mr. Belt's letter ("The 

 Glacial Period," Nature, vol. x. p. 25) to which Geologists 

 who have devoted much attention to the ice action will not 

 take exception. May I be allowed to call attention to onj or 

 two? 



1. I do not believe that there is evidence, which anyone 

 accustomed to glacier " spoor " would admit, of an extension of 

 the ice- cap so far south as the Thames valley. 



2. It is in the highest degree improbable that the shells on 

 Mo=l Tryfaen should have been scooped out of the bed of the 

 North Sea by moving ice and transported to their present 

 position. Apart from the dilTiculties of a glacier thus walking 

 so far up-hill, and of shells having e.scaped utter smashing in 

 this uncomfortable mode of transport, Mr. Belt has forgotten that 

 Wales was a centre from which radiated glaciers, and at one time 

 an ice-sheet, which surely would have warded oil from its own 

 hills the northern intruder. What evidence is there that the ice- 

 sheet ever followed its path ? All that I know points to I0c.1l 

 glaciation. 



3. Mr. Belt forgets that the various sea-marks are often at 

 very different heights above the present water-level — as is so well 



shown in Scandinavia — and that no lowering of the water will 

 explain this. The height of even 600 ft. whicli he claims is one 

 that rests on many assumptions and but little confidence can be 

 placed on the numerical results. 



It would be easy to discuss many other questions which he 

 raises, but this would occupy far too much space. My present 

 purpose is not so much to do this, as to utt-r a protest against 

 such a portentous development of a theory winch has for some 

 time past been assuming nightmare proportions. 



St. John's College, Cambridge, May 19 T. G. BonneY 



Lakes with two Outfalls 



It is quite possible that 1 am wrong in my memory of the 

 Nystuen watershed ; and as Prof. Stanley Jevons examiaeJ the 

 place critically, I can have no doubt that I am so. I passed 

 merely as a traveller, and described what I had seen, from a 

 memory, not specially sharpened by a knowledge of tlie impor- 

 tance of the point, at the time the observation was made. I 

 know well what tricks one's memory plays under such circum- 

 stances, particularly when one has been rambling over many 

 similar localities ; and my letter indicated that I was in doubt as 

 to the particular lake which gave the double outfall. I passed, 

 too, just after much heavy ram, and it is possible that the boggy 

 bottom which Mr. Jevons describes was temporarily converted 

 into the lake, which deceived me. I may add, that both the 

 guide who brought me over the mountains from Aardal, and the 

 Skydsgudt who took me to Skogstad, confirmed the double out- 

 fall. 



My object, however, in writing, was chiefly to draw attention 

 to Norway, as offering an admirable field for the settlement of 

 the controversy, without going to the wilds of America. If 

 there be such phenomena, and I believe there are, they may 

 assuredly be looked for in that land of hard granite rock, moun- 

 tain plateaux, and innumerable watersheds of all sizes and 

 varieties, and if the hundreds of educated Englishmen who go 

 there every year be only impressed with the importance of 

 accurate observations, the point may soon be settled. 



Certainly I agree that Colonel Greenwood, who has kindly 

 favoured me with a most interesting letter of advice, has done 

 excellent service by his quite justifiable incredulity, and I shall 

 myself be content to have made a mistake, if by it I shall be 

 the cause of greater accuracy in others. W. B. Tiielwall 



27, Burghley Road 



Glass Cells with Parallel Sides 



I SEND you a brief description of a method I have recently 

 employed for rapidly fitting up glass cells with parallel sides, 

 believing that it may be ol interest to your readers. 



A piece of indiarubber tubing (or of solid rubber) bent into a 

 semicircular form is placed between two equal-sized rectangular 

 plates of glass, the ends of the tube terminating at the upper 

 edges of the glass plates ; the plates are then held together by 

 passing two strong indiarubber rings over their ends. If the 

 rings are of such a size as to exert the requisite compression a 

 semicircular water-tight cell is thus obtained, which can be taken 

 to pieces and cleansed with the greatest ease. 



A trough so made served well to exhibit with an ordinary 

 magic-lantern the experiments described on pp. 173 and 174 in 

 Tyndall's " Heat a Mode of Motion," and smaller cells suitably 

 fitted with platinum wires, and held in the wooden frame of an 

 ordinary lantern-slide, enabled the galvanic decomposition of 

 acidulated water and of saline solutions to be thrown upon a 

 screen and thus rendered visible to a large audience. 



Queenwood College, Hants. Frank Clowes 



Brilliant Meteor 



When nearing Holyhead at 0.50 A.M. on the 19th inst. the 

 most brilliant meteor I have ever seen passed slowly across the 

 heavens. It formed near Antares, remained stationary for two 

 or three seconds, and then slowly moved to the northward, 

 disappearing in the Great Birar. Throughout, the soft 

 green light showed every portion of the hull and rigging 

 with as much distinctness as a number of pyrotechnic 

 fires could have done. The shape was that of au elongated 

 ellipse, slightly contracted at one end, with the major a.xis of 

 the apparent diameter of the sun. A short time before it dis- 

 appeared six sparks .as large as Jupiter were discharged from the 

 southern end, and I thought a crackling sound followed. 



Celtic, May 20 Wm. W. Kiddle 



