June 26, 1885.] 



♦ KNOWLEDGE ♦ 



553 



In 1S71 I saw in the Emjlish ilechanic a drawing of an apparontly 

 straight cut between two lunar lakes, which it was suggested was 

 qnasi-humau work ; but it maybe merely a crack j further informa- 

 tion seems requisite. 



Regarding Jlr. Mackie's other letter (1755) I do not think it 

 correctly represents what I wrote ; part of it I do not understand ; 

 and the.rcst seems rather a courteous effort to help me out of a hole, 

 by the apt attachment of a cosmical donkey who finds himself 

 " unbeknownst " equidistant from two equally fascinating bundles 

 of solar system, between which he (as I understand) trots up and 

 down while humming (to the music of the spheres) 



" How happy could I be with either 

 Were t'oiher fair charmer away ! " • 



I half fancy Mr. SI. has got the wrong tortoise by the ear in the 

 Achilles hypothesis. 



A magnet will take up iron only pro rati, and so long as gravita- 

 tion does not prove stronger. I do not think it is the poles exactly 

 which attract the needle : not even the magnetic poles. 



itany scientific men are of the opinion that the regions of space 

 are traversed by " magnetic currents." Also, that there are mile- 

 stones on the road to Dover. I hope this may make matters clear. 



IlALLYAEDf. 



P.S. In my letter (1757, P.S.) p/o/ii-presence should be pluri- 

 presence — a theological term, chiefly used of Satan (because omni- 

 presence is an attribute of Diety). I thick you have rarely printed 

 a letter more deUghtj'ul than that of "Commentator" (1750). 

 Bnt let me assnre him I do not disclaim special creation of man 

 any more than I affirm it. I simply confess I know nothing about 

 it. I think Professor St. George jlivart has admitted that it is not 

 of the essence of Christianity ; and lie is certainly an uncompro- 

 mising Christian. One phrase of "Commentator" rather puzzles 

 me : — " The excess are cut off, but, on the whole, there is room for 

 all." I think there must be a meaning in this. H. 



THE COLOUR OF THE MOOX IX A LCXAR ECLIPSE. 



[17S0] — The following account of Observations of the Lunar 

 Eclipse of October 4 last, made by Mr. James Smieton, of Brongbty 

 Ferry, possesses considerable interest in connection with the dis- 

 cussion on the Ruddy Eclipsed Moon which has recently been 

 carried on in these columns : — 



" On turning to some notes made at the time, I find that, about 

 the middle of the total phase, the moon appeared to the naked eye 

 as a dim bluish-grey globe, not unlike a nebula or tailless comet. 

 Its apparent, size, too, seemed greatly diminished." (This last 

 remark does not accord with my recollection.) " Seen through the 

 telescope, the details of the mountains could only be made out near 

 the edges, as the centre of the disc was shrouded in an almost inky 

 blackness." (Neither does this accord with my recollection, as I 

 saw the disc through the telescope all of a uniform, putty-like, 

 dirty-white colour. His station was a full mile to the eastward of 

 mine.) 



" About 10.20 p.m. the eastern edge began to brighten, and a 

 faint ruddiness for the first time showed itself. This state of 

 matters continued with little change till 10.45 or so, when, just as 

 the total phase was passing off, a brilliant streak of silvery-blue 

 light encircled the eastern limb (of the shadow), while the rest of 

 the disc glowed with the most delicate tints of lavender, green, 

 and pink. The order was as follows : — Xext the streak, lavender, 

 then greenish-blue, then apple-green, then pink, the latter colour 

 gradnlly blending into a coppery haze that covered the western 

 part. It may be noted that the ruddy tint which first appeared on 

 the eastern side gradually passed westward with the progress of 

 the eclipse. I have no doubt whatever as to the appearance of the 

 mddy tint after the middle of the total phase, though why it 

 should not have manifested itself earlier is difficult to explain." 



The explanation, I think, is that the cloud which hid the earlier 

 progress of the eclipse from our view gradually thinned out ; first 

 there was a dense cloud and total obscurity ; then a thick misty 

 clond, and the disc seen of a dirty white colour ; then this mist 

 getting less dense, and, as the light of the moon began to show on 

 the north-east of the umbra, a faint copper colour gradually spread- 

 ing itself over the moon ; and, finally, the mist still clearing, the 

 beautiful blue arc fringing the umbra and delicately shaded, as my 

 friend describes. The faint indication of moonlight on the north- 

 east, and the first appearance of the copper colour, being exactly 

 coincident, seemed as if the one was the cause of the other; but I 

 fancy this could not be (?). Sene.x'. 



• A neat adaptation of the old schoolmen's definition of Nothing 

 — Chimcera iombitans in vacuo. 



ON REFLECTION. 

 [17S1] — As regards the rolli-etiou puzzlo of " M. T. 11.," already 

 noticed by myself and other correspondents, does it not follow that 

 if light bo due to waves produced in a medium actually present, 

 and if reflection be merely a change in the direction of such waves, 

 due to their falling upon a surface which they do not peuotrnte, 

 the waves must travel in tho now direction (i.e., reflection must 

 occur), whether an eye be present to perceive them or not ? 



W. H. G. 



INFINITE niVISIBILITY? 



[1782]— "Uallyard's" letter (1,717) still cannot get over tho 

 infinitely divisible atom. I am in tho same predicament : there 

 ought to bo a limit. Tho difficulty consists in this : If I havo an 

 "atom" or "any quantity" of inattor, I can "halve" it. Of 

 course, tho half can bo divided again, and so on ; but my reason 

 cannot follow. Why? Because it is "limited," "finite"; but 

 logic tells me that thoro must bo "infinite" division "possible" 

 if there can be "infinite" mnltiplicaticm, or else mathematics 

 have no meaning; although it is not practicable to deal with 

 "infinity," either small or large. Let "Ilallyards" endeavour to 

 calculate how many " mathematical " points would make, say, 

 half-an-inch ! F. W. II. 



UAECKEL ON MIND. 



[1783]— If Mr. II. A. Bulley, letter 1764, will read Haeckel's 

 "Pedigree of Man" (there is an English translation) ho will find 

 him neither an " extreme " materialist, nor " denying dogmati- 

 cally." Haeckel certainly denies various dogmatic assertions, 

 which, from their very nature, are imposssiblo of proof either by 

 experimcTit or reason. All the theories set forth are endeavoured 

 to be exjilained by reason of empirical proof, logic, or probability. 

 And surely it must be more satisfactory to explain phenomena in a 

 natural, reasonable way, than by the "assumption" of the super- 

 natural and the miraculous. 



My simile of mind, with the " scent " of a flower or the 

 "reflection" in a glass, was meant to show that " mind "_ is a 

 res media, a resultant, an effect of two material agents, in itself 

 intangible yet real. As the scent proceeds from the living flower 

 by the influence of sun warmth, so thought proceeds from the living 

 brain under the influence of stimuli. Or as the picture of an 

 object in a glass is intangible yet real, so is mind, thought of an 

 object, in the brain real yet intangible. 



Therefore it appears to me that if one or other of these factors 

 is absent or inactive, the effect in the soul or mind goes also. 



In conclusion, Haeckel does not deny the existence of " sonl" as 

 a persistent, imperishable " force " in nature. On the contrary, he 

 says. All nature, i.e., all " matter." At all events, all organic matter 

 is, in a sense, gifted or possessed of a soul. 



Since whatever is, was, and will be, there can be only " change " 

 —constant, unceasing, varying change, as it seems to me, in one 

 endless, ever-revolving circle. I would alter the words quoted of 

 Montaigne, Man wor'rs according to tho causes that work upon 

 him. F.W.H. 



THE IMMANENCE OF LIFE IN MATTER. 

 [1784]— If "Commentator" will read Haeckel's "Pedigree of 

 Man " he will find that this follower of Darwin does postulate what 

 "Commentator" calls "self-existence" to all matter; innate, 

 inherent, self-existent energy, which all matter, organic and in- 

 organic, is everywhere possessed of. There is a "soul" in every- 

 thing; matter gravitating moves of its own accord, magnetic iron 

 attracts or repels, as do bodies electrical attract or repel each other. 

 There is chemical affinity, the elements of one compound separate 

 by contact with another, form fresh combinations, &c. — in short, tho 

 energies of matter are only at present beginning to be somewhat 

 understood. As to that convenient progenitor, at least all living 

 matter does now begin with simple protoplasm, as embryology most 

 amply demonstrates. Is there a plant, beast, or man which has 

 not had to pass this first stage of existence in its life ? There is but 

 one law, and its working seems to me uniform, viz., necessity. If I 

 understand Darwinism aright it means constant "change," constant 

 motion; design, creation, arise first in the human brain, they are 

 "ideas" only; for who designed the "designer," or who created 

 the creator — those convenient names to cover our ignorance ? 



F. W. H. 



IS DARWINISM DOUBTFUL ? 

 [1785]— The probability of any theory being the true one 

 depends on its power of harmonising a greater number of tajta 

 than any previous one of similar pretensions. Darwinisw or 

 evolution is admitted by friend and foe to fulfil this condition. 



