March :5, 1882.] 



♦ KNOWLEDGE • 



391 



!3[nstotr6 to Coriedpoulifnts, 



* ^* AU communxcationa for the Editor rrquirituj early attention tkould retuh the 

 Office on or bi^fore the StUurda) preceding (*« current iiene of KkowlBDOK, the 

 increatini -irrulution of which compete tit to go to prete early in the veek. 



HlXT;; TO CoBBKSPOXOBirrs. — 1. Xo guettiont aiking for ecientijtc information 

 eanhe anirrred through the poet. 2. Letter! ernt to the Editor for correepondente 

 cannot be forwarded ; nor can the namet or addrettet qf correepondentt be gicen in 

 tmewer to pricatc inquiriet. 3. iVo queries or replies savouring qf the nature qf 

 adcertitemcnts can be inserted, i. Letters^ queries^ and replies are inserted^ unless 

 contrary to Sale 3, free of charge. 5. Correspondents should write on one side 

 onh of the paper, and put drawings on a separate leqf. 8. Each Utter, query, or 

 rtply should have a title, and in replying to letters or queries, r^erence should be 

 made to the number qf letter or query^ the page on which it appears, and its title. 



- S. Question answered at p. 94, No. 5. — R. Mortimkb. Xot 

 :>«. Other matter (about probable explosions) suitable for 



papers — next time you think they are likely to occur. — TvRo 

 : ■NOMicfS. Subject of earth measurement not so simple as you 



to think.— Science and Akt. Fear most of our readers do 

 <are twopence about the rules and regulations of the 

 oe and Art Department ; so can hardly find space for article 

 ing that they •' muchly need correcting." — J. MfBRAV. Jly 

 sir, it would take a page six times as large as ours to present 

 diagrams properly. The .sun may expand our '"atmostphier" 

 i'3 one side, which gives to it a rotating motion, and " our 

 1 approaching the sun down the decrescendo line." may be 



■ cause of solar time," but these profundities are not for us. — 

 :alkenzie. Thanks. — F.J. B., Jo.s. R. Geeex. Thanks; but those 



■ cts already provided for. — Reduiti^. You calculate ^^•ithout 

 dering interest ; that might bo the brokers' way, but it is quite 



! rect. — Ail Roots. I would rather not " extract for you the fifth 

 • <{ 5053632, or the eleventh root of 11, or the thirteenth root 

 O. &c.. lie." A rtde can be given for such cases, but no one 

 works them out otherwise than by logarithms. — J. OEMTnw.^ixE. 

 not know " why Government did not appoint" mo " Astro- 

 1' Royal " ; nor can I conceive why I was not appointed to the 

 niand of the Channel Fleet. Perhaps it may have been ttat a 

 ial training is required for these offices, and that I have had 

 nunc. Or it may be that I ought to have offered my services in one 

 or other of those capacities. When I do, I shall expect a favour- 

 able response. — Enqciree. Xot S"6, nearer 8"'88. For the calcu- 

 lation, tr>- this : — Earth's equatorial radius (or say, 3,960 miles), at 

 aun's distance, sustends 8"'88. Hence the full ciicumference of a 

 circle having sun's distance as radius 



= 3,960 miles x 360 x 60 x 60^888, 

 •nd earth's mean distance is equal to this distance, di\'ided by 

 2x314159265. — A. Rischgitz. Fear the geometrical proof is 

 fiuniliar to most mathematicians. — T. J. Potter. Thanks. — T. R. 

 Allinson. Thanks for vegetarian great men. But wait till list of 

 carnivorous great men is published. Why do you include the 

 notorious "eccentric" Sir Richard Phillips ? Two-thirds of the names 

 you give are of such a class that we might fill ten numbers of 

 Knowlepge with the like, if once we began.— T. Wolstenholme. 

 Thanks ; but instances of animals nursing young of other species 

 now sufficient in number. — Wer.nek. I'Uere is " no plane of 

 oscillation of the earth." Cannot understand question 2. — 

 H. M. You will have noticed the misprint 37/5 inches for 

 <y377o. — E. T. Whiielow. Thanks ; but Mr. Brothers has promised 

 ■ach papers. — J. P. S.^ndiands. 1 am sorry that you think you 

 bave been treated unfairly ; but if you remember the rule you in- 

 fringed you will see that 1 had reason to complain, not you. You 

 eonmder that "Found Links" and my own article on "Luck," 

 touch on religious questions ; therein I am disposed to agree with 

 yon. No subject of which we treat in these pages can fail to-do so. 

 Bat you wish to emphasise, and 1 decline to have emphasised, the 

 diSsrence of view which may exist according as these matters are 

 tiewed from different standpoints. Leaving Professor Wilson to 

 daal with "Found Links," let me illustrate my point of view from 

 1^ articles on '" Luck." There can be no doubt that some minds 

 •l^ect to a consideration of that subject in which the influence of 

 ftwidence is left, ex necessitate, out of consideration ; but you are 

 ■0* to consider that the entire absence of any direct discussion of 

 Ptovidence signifies an absence of recognition, still less a denial of 

 ita effect. You wish me to say what my views are in this respect ; 

 but this I decline to do, beyond such general reference to the matter 

 as you find in my last article on the matter, page 311. If I allowed 

 myself this privilege,^ whether my views are on your side or 

 not, I could not refuse the same pri\'ilege to others. Believe me. 1 

 have no wish to act unfairly, and I do not think I can be justly 

 charged with so doing. — Igxobamcs No. 1. You are right, see 

 editorial letter on the subject in last number. — E. Clodd points out 

 that as Prof. Tennano is dead (he died while 1 was abroad), letters 

 addressed to him as suggested will probably not reach him. — C. J. C. 

 '^n Sunday night, Feb. 19, at 7.43 p.m., saw a magnificent meteor. 



colour deep orange, path very short, leaving a trail of fire about 

 5". — Ignokamis No. 2. If we take De Vico's estimate, the day of 

 Venus is, as you say, very nearly of the same length as our own, 

 and, as you also say," she certainly has no moon whose tide- 

 raising action could have lengthened it. But the sun would 

 raise high tides on Venus, supposing her oceans like ours. 

 An orb's tide-raising action varies inversely as the cube of 

 the distance. Now, roughly. Venus's distance is seventy-two 

 hundreths of the earth's, and cubing this proportion, we find that 

 the tide-raising action of the sun on Veims exceeds his action on the 

 earth in the same degree that 1,000 exceeds 373. Whence it 

 follows, that as the sun's tide-raising action on the earth is two- 

 tifths of the moon's, his action on Venus exceeds the moon's action 

 on the earth as 2,000 exceeds 1,865.— G. A. Newcomen. Thanks. 

 Answer a little too difficult. — Disappointed. Are we too mis- 

 cellaneous or too astronomical ? We can't be both, yon know. 

 How^ever, in our last number, we were more astronomical than 

 we have yet been or are likely to bo again. — V. S. says that in 

 most ships now the *' forecastle " is under a raised deck forward, 

 which is called the " top-gallant forecastle." — M. Welb, Webb^ 

 or Gei.b ? We iiiu.';( insist on the rule that letters and queries be 

 kept separate and properly arranged for the printers, or wo cannot 

 deal with a tithe of the correspondence. — Geo. M. Not correct. — 

 E. M0E.TEM. Thanks, question sufficiently answered already. — K. 

 Thanks, picture almost too rough to give any idea of what 

 the objects may have been. — F. W. Cory. Probably you are 

 right in thinking that "A Constant Reader" would not find 

 the weather prognostics for liis district so often erroneous 

 if he combined his observations mth those made by others. 

 Your letter is somewhat too loi-g for insertion. We fear 

 your suggested increase in the numbers of meteorological 

 observers would only have the effect " of adding " (to use Sir 

 Geo. Airy's expression) " millions of useless observations to the 

 millions which already exist." — J. J. J. Some of those Planchette 

 experiences are, I know, very singular, and very difficult to explain 

 as phenomena illustrating the influence of imagination on corporal 

 actions, which, nevertheless, I cannot but think they must be. I 

 could not well open the matter for discussion here, simply because 

 we could have no assurance of the truth of the accounts sent us. 

 You are not to imagine that I question your statements — in fact, I 

 have had somewhat similar experience within my own family circle. 

 — H. A. BuLLEY. Have given more than due space to moon's in- 

 fluence, which has been proved to be slight. — H. A. B. Lightning con- 

 ductors do not act by repelling lightning, but the other way. — 

 H. MuiRHEAD. The brain-wave theory must be put on a more 

 scientific basis before it can be regarded as a part of knowledge. 

 We have no experience of ethereal waves acting directly on the 

 brain. What is the organ by which such waves affect the brain, 

 and how ai-e they conceived to act ? — J. Mackenzie, M.D. Nay. 

 Admitting the abstract of an able lecture by an eminent doctor 

 does not mean that we open the pages of Knowledge to the dis- 

 cussion of a medical subject. A paper sent us about vaccination, 

 whether for or against, would be submitted to a competent medical 

 advisor, and if regarded by him — first as sound, secondly as suitable 

 — it would l|B,ve a good chance of being admitted, if it were also 

 short. — Lestor Francis. — If you notice, we are beginning micro- 

 scopic matters — but at the beginning ; presently we shall come to 

 details. You see the difficulty of getting all in at once ? — H'Sett. 

 Your views seem near the truth, as far as at present seen, though 

 it is not considered that evolution is necessarily advancing. We 

 thoroughly agree with you that argument with persons unacquainted 

 with geological eridence is utterly useless. We would insert much 

 of your letter if our space were not so crowded. Note promise and 

 hopes expressed in our last, however. — Marshall Leigh. The manu- 

 facture of artificial wine hardly in our line. — J. A. S. We are likely 

 to have chemical papers soon, but for your pm-pose the Chemical 

 Neiiv, edited by Mr. Crookes, is the very thing.— J. B. Dimbleby. 

 The time measurements of your association are wrong, but how 

 can one show it ? Transits do not always occtir in pairs, as yom- 

 society seems to think ; and some of your teams (poor Venus in 

 teams) would be very lop-sided. — John Gledstose. The moon can 

 nearly always be seen in that way, in clear weather, when new. 

 In America I have seen the unilluminated part (or rather the part 

 not illuminated by the sun) when the moon has been nearly half 

 full. The darker part is illuminated by earth-light. Our earth 

 would appear as a large nearly full moon in the sky above those 

 parts of the moon. — R. Mortimer. Yes, your warning reached 

 the office of Knowledge before the colliery accident ; but we 

 did not see it till afterwards, and we have no daily issue. 

 Such warnings, to be of use, should be sent to the daily 

 papers. — William Miller. We cannot answer questions through 

 the post, nor give in Knowledge an opinion as to articles adver- 

 tised therein ; that is, not in reply to questions. Consider how 

 open to abuse such a course would be.— rH. H. Tlie tides raised by 



