♦ KNOWLEDGE ♦ 



[Aug. 21, 1885. 



If 



would they get away so far from the main body ? (I 

 ion that last year I watched for them after midnight, but 

 as 1 saw none in half an hour, I went to bed.) 



4. Is the following a valid objection to your theory of a meteor's — 

 or rather a meteor — train, being ejected from planets, sun, or stars ? 

 Observation or analogy show that all these bodies rotate. If a 

 shower takes two days or two years to fly past a given point, we 

 must presume (unless a lengthening-out happens in transit) that 

 the shower took two days or two years for the process. But if the 

 process did last so long as this, it would be impossible for all the 

 ejected matter to be expelled from the rotating body in the same 

 direction — unless, indeed, the material was discharged from the 

 poles of the rotating body. 



The fixed radiant-point question is very interesting, and I hope a 

 good exposition of the subject will appear in Knowledge. 



More Light. 



[1. Meteor systems lengthen out. 2. This agrees with my theory 

 at least as well as with Schiaparelli's. 3. The "gem of the ring " 

 of Leonids has passed completely away from the neighbourhood of 

 the earth's orbit. We may, however, be shortly expecting to see 

 some of the meteors scattered in front of the main body. 4. If a 

 shower takes two days or two years noiv in passing a given point, 

 it by no means follows that the original cluster took that time in 

 starting — on the contrary we know the present extension of the 

 flight is greater than of old. Hence this peculiarity implies no 

 objection at all to my theory. 



Lastly I may remark that my theory was suggested years after 

 I had examined and described the peculiarities " More Light " 

 touches on, besides a number of others which few of those who just 



them. My essays, written in the years 1866-71, on the November 

 meteors alone would make a good-sized book. — R. P.] 



INVISIBLE SUNS. 



[1876]— I was much interested by an article by Mr. Proctor 

 which appeared in Knowledge a few months ago, pointing out the 

 comparatively small number of orbs which are likely to be in- 

 habited at any one time. It seems to me that the same chain of 

 reasoning leads to the conclusion that the universe must contain 

 many invisible suns — great orbs like our sun, which have cooled 

 down sufiiciently to emit no light of their own. 



Some of these may probably be in a condition, as regards tem- 

 perature, permitting of their habitation by living creatures. It is 

 a curious speculation, What forms of life would be found on such a 

 globe, illuminated, as it would probably be, only by starlight ? 



Mcs.^FiK. 



SUN WORSHIP. 

 [1877]— If the writer of the letter No. 1835, page 79, in Know- 

 ledge for July 24 of this year will give in Knowledge the source 

 of his information respecting the sun worshippers of Mexico and 

 Peru who " held dogmas almost identical with Christianity," I shall 

 be extremely obliged. Zeteo. 



LIFE IN THE MOON— DEATH OP PLANETS— BLUE SKIES 



—MOISTURE OF THE ATMOSPHERE— SOLID OXYGEN- 



THE WATERS ABOVE THE FIRMAMENT. 



[1878]— By referring again to letter 1812, " Hallyards " will 

 find that the remarks contained therein, concerning imaginary men 

 in the moon, are just as applicable to his new example of Uley 

 Bury as they were to the case of the Pyramids, which he has seen 

 fit to lay aside. 



Unless " Hallyards" can demonstrate the probability he assumes, 

 the age of life in the moon must have overlapped a period, the 

 exact counterpart of a given period of life on the earth, and yet 

 not have exceeded the present ; he may throw back the age of man 

 and his work as many centuries as he pleases without affecting the 

 question in the least. 



In the absence of an occasional fact or even probability to guide, 

 it is penetrating far enough into realms of imagination, to picture 

 either an inhabited moon, or a moon never the abode of life, without 

 defining a limit to the civilisation or brain power of the merely- 

 conjectured Lunarians. Furthermore, the wish to compare speci- 

 mens of human work, lunar and terrestrial, without a comparison 

 of the circumstances giving rise to the work in either case, shows a 

 decided tendency to build " castles in the air." 



I must inform "Hallyards" that I do not "contend" for the 

 "man in the moon," my contention is simply that there may have 

 been men in the moon for all he has said to disprove it. There are 

 perhaps more weighty reasons against an inhabited moon than 



those advanced by "Hallyards." (By-the-way, I should like to 

 hear a few particulars of " Uley Bury" and H.'s authority for its 

 remote age.) 



" There is nothing to show that planets die, so long as they have 

 their sun." Which is (or rather was) the sun of the moon, the 

 earth, or our sun ? The earth, I should think ; and since the 

 moon's sun has cooled down suflicient to bear life, the death of its 

 planet can be easily understood. What will the earth be like when 

 our sun is cool enough to bear life ? 



Tlie "positive fact" that northern skies are bluer than those of 

 the "sunny south" needs some slight corroboration. 



Walking through a picture-gallery a day or two ago, I could not 

 help noticing how different tints of blue (independent of cloud 

 colour) were characteristic of different latitudes. We are all prone 

 to mistakes (" H." not excepted) ; but seldom is the fact so ex- 

 emplified, as in the case of our artists in their endeavour to repro- 

 duce nature, if " Hallyards " in this instance be correct. 



Once again, " Hallyards " has supplied me with the argument 

 against himself. A better proof that the amount of aqueous vapour 

 must be greater in warm climates than in cold, I could not have 

 wished than that instanced by the sudden introduction of " French 

 rolls" into this discussion. Because in France, " rolls " and things 

 in general are unusually dry, he concludes that the atmosphere 

 likewise is dry. Will " Hallyards " explain where the moisture of 

 the rolls, &c., has gone ? It has simply evaporated, which means, 

 the solvent power of air being raised by an increase of temperature, 

 the water required to saturate it is drawn from wherever water is 

 exposed, be it lake, river, rill, or " roll." 



I am asked to " demonstrate that (the atmosphere of) the 

 parched Soudan has more water than the storm-swept Arcades." 

 If the foregoing example is not suflicient, the following figures will 

 explain :— 



Air absorbs one hundred and sixtieth part of its weight in 

 aqueous vapour at 32°, one-eightieth at 59°, one-fortieth at 86°, 

 summer heat, and a twentieth at 113°, intense heat. 



As to solidified oxygen and nitrogen, like the discovery of the 

 conjectural metal hydrogenium, it has been accomplished num- 

 berless times within the last twenty years, if every scientific 

 announcement of the fact is to be credited — we have been deceived 

 so often that incredulity is somewhat pardonable. I made the 

 assertion that these gases could not be solidified on the authority 

 of at least half-a-dozen standard Chemistries, but I will not dis- 

 pute the point, as it is of no moment. I admitted in last letter that 

 all gases might be solidified. 



Referring to the " waters-above-the-earth " theory, a scanty 

 glance through the first chapters of Genesis will show " Hallyards" 

 that its origin is shrouded in no ambiguity, and we are not even 

 dependent upon the Hebrew records for its exposition ; it was an 

 universal idea. Alex. Mackie. 



[The question of the possibilities of past life in the moon though 

 suitable enough for suggestions, is not one for discussion. We can 

 fancy many things but can establish nothing. — There can be no 

 doubt that there is more moisture usually in the air over hot 

 regions than over cold ones. Oxygen and nitrogen have both been 

 solidified, — and by more than one process. — R. P.] 



EVOLUTIONISM. 



[1879] — So much has been lately written in Knowledge about 

 the Darwinian theory, that perhaps I also may be allowed to raise 

 a point or two that seem as yet untouched. 



I cannot help thinking that the reason why Darwinism is so 

 generally accepted at present is because it is a theory so admirably 

 suited for our present phase of thought. In these days of inven- 

 tions, of rapid advance in science and in material civilisation, 

 when the ideas of all instinctively turn, whether they will or not, 

 in the direction of the unlimited development of human resources, 

 the notion even of an inexpansible millennium becomes too narrow 

 for us, and in such an age this new evangel of progress could not 

 fail to have an immense following. A century ago, had there 

 been found a historian who could philosophise on history as we do 

 now, and could he have foreseen the enormous strides that have 

 lately been made in science and its application to material re- 

 sources, he might have been able to predict that a theory of this 

 nature would arise — he might even have laid down some of its 

 main characteristics. The moral to be drawn is this ; the more 

 completely a theory is the creature of its age, the more deeply 

 ought it to be distrusted. 



Again, it really seems to me that the " struggle for existence" 

 has too much to carry. It appears to be forgotten that slight 

 variations (the only kind admitted) are alsolutebj and totally in- 

 effective in this struggle because their results are so small. To 

 illustrate : I wear moustaches on my lip which in eating con- 

 tinually get inconveniently into my mouth, but are most ungraceful 



