150 



KNO^A^I-EDGE 



[Dec. 16, 1881. 



grr»t iir«l. Thu^. if )-f 



uia 



• (H.ifi. " to him (Im wno « French iloj,-) ho -^ 

 ^k.< > nui.e'.bi)ul u nnir (o the -oud.I of th« »or.l iw Ihn ..■•t;' »' "'".^/i""". '" 

 ™ ho .,.rd cuckoo, but uo o-«r<.r. If cno hnd b«cn loU he «";' " h"^ 'h^""^'' 

 ......1.1 l.i.,...lonniu«l oa well for ihnl word, or forhalf-n-donu olhom. Jn sonicnucn 



r^T dm.Mir X d" "•' cen ind herd by M . Uibnilr, " could ..jr. in Oerm.n 

 r«!'coS;i ,U; Wo hid a doK „n,.o «hich could ,ing, but ib.t "HU'rcd » Ro^' 

 di^l of "iA«lio believe " too.-.Ioiin Stkhlb. Your eipUnnlion not ncim«r>. 

 b^ wcU rTeived tteienoo no more quclion. tho .un'» heal th.n «. quo.t...n 

 Ih. he.t ofTflrc »hich ..rm,. u,'-Alt..b. Query »' "'7.;^/ "»«"■'; 

 r^^.eirn->" "f '^^ "o «S ■tV^n'ot.-XtM;'^ 3;M.^ 



i, nn«und. for the ar^gl i» obv.ou.lv ""'/""''":?- "'"^"^"b^'^i 

 Your flrrtri-nll uraount. to th.R, that ■' T"" ''7« .'n':\?i^r r^m Xh you 

 moves in the Fifteen I'uizle, you can como back to the po.ilion Irom wlucn you 

 ■twted- your .ccond, to thi». that startinR from a cerlmn ponlion and nmkinK 

 „" number of move, you cannot work b«:k to a certam other P«'''°". f^'^^y 

 re/emblinR, but not identical with, the former. But thui does not depm e ho 

 puicle of ita interest as a mathematical eniRma. 1 ou can .>>»'-'i';i' ,"■>*". P™'':'; 

 Kh, numerous eiperimenta ' ' (only) that those ''-">'«"« '°7"»''';'/°! Xr 

 arc twenty billions of different roi.l.ons which can bo attained from one or oiner 

 of your two sUrting pontions. If you had (that is. if vou had worked at the 

 puiilo ten Umes or so a day. durinR a life of some twenty thousand years) there 

 puiiic 10 _u ^ ^^^ problem-pretty, though not difl!cult-of showing why 

 variablj- be attained. T'"^°^''«''°'f,"""'™'„P""'®Jfihp'smXsl 



Tbaskitar 



that on p. 117, but if o». «, 



for your commimication all the same, 

 with regard to space. Note bcginni: 

 and reply toW. K. W. below.— Jauk 

 shall appear shortly.— Eclkcticcb. 

 lla\c been obliged 1^ much shorten y 



IferUit 



eive such note* M Jtn 



iderstand. — J. P. B, 



'enpondctio* 



woald still 



these rMiUts can invariably be atlamea. incnmereis iiicii,:oi ^.^ 

 how to attain any assigned position from another of the samoord 

 number of movei. On the whole, it is as pretty ahttle pu^^le, I ""f. ff""^ '^ 

 vented since "Sohtaire," which involves "on""'"-? neat mathematical reAat.ons^ 

 C.IROMO. Thank, ; but question, suffic ently <^^Y."i'^"'^^~^^^oIZ^^ov, 

 Your feara were expressed for others, but seemed to be yours. Anyhow, we know 

 your lettor would have raised most undesirable controversies.— !■ . 11. »• '",'; 

 lunar iUusion is not dependent on the vastness of the sun s distance "• » 

 eiplanaUon was sound. The plane through the observer s eye and '!"' ^''""'''*; 

 sagitta due south passes through the east and west points on the horinon. \\ omcl 

 mfntyour letter did space permit - R. Ravmbnt. Hope shortly to insert your 

 fe7ter^-A.v Admikbh'^ You are very good, b"' fTJT'^rSl^?,°uTenU " 

 would not quite Uke it.-E. BlKOEss. Thanks for " Help to Chess Students, 

 Crowded out at present.-ATHOS. Of course you are "K'>1 ■",'^7"'^^''' ''i'' 

 solar dark bnes, as interpreted, prove the sun to be intensely hot The argu- 

 ment would beabove comprehension of the paradoiere, ho^evei-.-RoD S. Coccn 

 Letter «li.<ill shortly appear, it possiblc.-G. W. NivEN. Short notes on such 

 trick, would suit well enough.-tS. N. H. O. No space at present Thanks for 

 replies.-A. L. 8. Thanks for account of lunar rainbow (wl'V call it Ins 

 Lunaris?). No room for it at pre.sent.-J. Fbaseb. Still hold the 

 i^'epted theory of the tides. No earthly reason why 'he earth should 

 fidl into the moon. Your theory wholly untenable. ^T. Thanks. - 

 F. W. C. Cannot insert answers recommending instruments by parti- 

 cular make™. We are sure of your bona-JiJe, ; but others """''1 '^''',", "f" 

 to do Ukewise with less worthy motives.-J. M. Many thanks; but the 

 question had been answered suffii-ienlly, though we could not lind room at once 

 lor reply -W F Dknni-X-o. Thanks; your letter shall appear.-CABLO f. 

 JonssoN. Thanks; but we tnko replies respecting comets as part of subjectwe 

 are discussing in articles-if only we could get a line or two m 'f ««*"£;, O'^" 

 qoestions aiiswered.-H. O. HoLliNOWOETU. WiU try to Bnd tfom-D Aktag 

 iJax. Airy'B Essay on " Undulatory Theory of Light" (m his malhematical 

 essays) Lloyd's and Potter's treatises were what we used to read at Cambridge. 

 -IsQuiKBB. Moore-9 "Lalla Rookh " is not a recognised astronomicjJ 

 authority ; stiU " half retired •• (from the earth) ivoukl correspond nearly enougn 

 with Ume when Venus •• looks loveUest."-S. N. W. \ ou evidently have not yet 

 "rasped the meaning of the modem theory of evolution, lour remarks apoly 

 well to such theories as Lamarck's and others ; but they arc dead; why play 

 Falstaff at Shrewsbury over them?-J. D. " As fast as we fil a telescope, you 

 say, "the earth's motion ought to displac'c it." That is just what the earth 8 

 motion does. It is this motion that the driving clock of a telescope is devised to 

 .■orrect, by constantly carrying the clock the otherway.-F. H. 8., J.Gotti-bied, 

 and otherJ. Thanks ; " Mapc Squares " crowded out for the present.-L i-EBllBBS. 

 Received ; thanks.— Mabel W. L. Pressure of time was the cause of printer s 

 error ■ but it was of the less importance, as Brewster's ideas were entirely incorrect. 

 - S U F — Wepreferour " happy laughter " to be independent of comparatively 

 " low repUes." Your method of studying the luminary in ouestion is uiisound.— 

 .1 Gottfried. Thanks for your magic squares; the method shall appear. Ihereare 

 others yet.— ANoairw Aitkbn. Your answer to Cymro's question is sutftciently 

 sound, but we have not room for second solutions. The arst was correct The 

 llrst pivrt of answer to Query « is also omitted, as the triseclion of a nght angle 

 famiUar to all students of geometry. The other solution is really the same as 



.. ,,r >,...:» „„.,._„,. „ot BO crowded we would pive It. Thanks 



We must ask you to consider our position 

 ig of our letter in correspondence column, 

 s SUAW. Article on " Right-handednc-ss" 

 We give you alone this fiom de plume now. 

 jur letter.- W. U. R. Thanks, but longer 

 parts could not be placed. There is no 

 Utin word meridionalii). MerUmmm is the word. Albeit we leave such 

 point, to the printers.— W. T. Lynjt. Thinks, but the ciact time when 

 Halley's comet was Brst obsen-ed in 1759 is not Ukely to interest the majority 

 of our readers and space considerations trouble ns. We put in your flrst letter, 

 heinuse it involved a correction of our own statement . Otherwise, these questions 

 <pf dates priority, manner of observation, and so forth, seem of httle importance 

 How often has the error about Tycho Brahe and the new star been repeated, and 

 what harm has it done? We must not be microscopical in such matters.— 

 HtBlus. To save space, have been obliged to incorporate your letter in our own. 

 — Alki. J. E. Your 3-equare punr.Io is very neat.— Musicus. Why want to 

 learn how to " get in the way of talking " while you play the piano? Did you 

 ever hear anyone do so who had the least feeling for music? hone such can play 

 well when oiJieri talk. Probably, it i, as easy for a mere " performer to talk 

 while he phiy, as to talk while someone else is playing, and as diUlcult (rather as 

 impossible) 'for a real musician to do one as the other. To anyone with the 

 .lighteot particle of musical feeling, there can be nothing much more trying 

 than to hear people talk while a noble air is nobly rendered, unless it be 

 to hear a skil'ul executant talking while the notes of a noblo J;r P»«» 

 wilhout life or eipression under hi, agile but not musical lingers. —K. F. H. 

 ■Hianks.- Herheet R. Weller. Unquestionably a meteor. Some meteors move, 

 apparently, quite slowly, and the larger often have the comelic appearance 

 vou indicate -H. A. S. " Puizled's " problem is sufficiently eiplained. It is 

 "much older than the publication you mention, though, doubtless, new to him. 

 Your other problem, depending on half a live man being equal to a man half 

 dead is amusing, but would be out of place here.— K. J. P. Why w-iU corre- 

 spondent, take 80 much care to make their communications too long for inser- 

 tion ?— A BioLonisT. Your reply to No. 62, if inserted, would lead to others 

 being sent, which might read Uke advertisements. Thanks equally.— J. H. W. L. 



We will 



Si[i'B.Moi"muci;;' we fear, over Ih.- «"•""";;■■" 



K. J. Baonm. Com-ction inwrted. ^''*"''"- -— J,,; „„dor.i 



suggest with }'l"f-"J'^''l ^™':^;.5rcnT" n° t;^ ^..^^^^ 



Unow«--th«l fancy often mimic, reason. . . 



anow, iimi i»" J g^j misjoming •hapea 



Wild work produces oft, and most in dreama 



111 matching words and deeds long pastor late. 



lU roalcning wo™ ;, hard^ eip inatorj. The oo««0on 



the ■"'^^'"'..iH" n o°i tfe "arth JuffidentiT prov^e that these ?<?!«. k"« 

 already answered, we omit, "P^* ,*" ?f "?XSent "-H. E. W. W. 



'h"ol'ut'';:ind"a.;"d rh":Velo";ory ch"'e"eed'','trat of^ither The prindjl. 

 absolute wind, ana 'ne veiotiij "■ j Lampbet. UnqucstlcliaWj, 



^L'"" Iniwle r o"f '?hrA"de'nt.?- wo'u'ld L Juu'of interest ^f-' --a™.. .* 

 I'de^^Lowle ge; andocc.iona.pape™ onth^.^^^^^^^^^ 

 cannot, as yet, arrange for '"e sysieniaut " ^, ^jjeduo attenUoB.— 



{<Vv»v.-i'i"Lvr ffiVs fV7S«V.^'^^^^^^ 



'sfarT^n S^ove^ber,^"!^ M^ » ^^^^^^^^ 



unfair ? There was, of oouye less ^"""P™*''''?^"'^^ ' th"^4«'p^DdJSS 

 not have been strange h^^'*""' ^7" r°"„ were interesting. TwoVeren*- 

 occupled.too much space ^^^^-^vVbeVn pur.rong "he origi'nal article, .^ 

 ^L'^i^:" r, mXt?;'.uT|ested that the" -"" should J.e put a^ong^ 

 „„„j„r,..o Yoii must remember that we have to consider tnose woo »ui 



nereafterwemu.stbe more 8tr,ct, though as -ti. ^^ ,«h«ic.l 



l:r'"M';rlin°8fof . p^£cLf^^^^^^^^ 



"3 hT^th. However, the Indians who B.f .''"Sl'l.rof flesh-L?°t wWd. 

 cated otherwise. The ouestion "hither it is the use of flesh meat 



has raised man above \is ''I'-'j^, ,*^"'?»'!L''jJe of "he^dL.«ed high 

 cussion. It scarcely seems probable m the face 01 tne a b_ 



p, to lower prices.— T. K. ALttusos. '^»'_ "5 1, A„ better than cet 

 „,„. ■-"Orable.-ABNOtD Ramspbx^ y^ebb'^ "cele^tfi Obiectl lor Comio. 

 Midler's smaller map »« <he m^n or Webb^ Ce^e ^^ ^^^^^^.^ ^ 

 Telescopes," '°,«hich there ,s an eiceiieni map g ^^ pubUshere, would 

 book is about lOs.; Madler 8 map alone, from the Ixep^^^ inst^ent 

 cost, 1 suppose, a shiUing or •"■yThomas ^°^^k^ > °"^ 6^ g p , eorrectrf 



tS^'w^ n "ne who ha: rea'd LyeU's ramarks on 'he book in b. 



Children differ singuhirly. Certainly «'"^^,^f ''°,' ' ',^''1^ but her novel-writing 

 not of itself show that h-r br«n was ab,j^,™aUy <U,v elo^^^^^ h^^ ^^^^^^ ^ B 



rp-e^^c'^:fTori^t^terr;?ur ¥te ^i^ -J^,"- ^'tik'T^^ltllSl: 



fc"g?vrw^e^?y^rthTrrp^ortii?.wof^rf - b^e a-a.-w.,^. 



tiopc lo ^>t ,**'^" J . j„„„ „;tVr,„t imurini' the maps. Doubt it. — A. ■*• 

 vclumoneeii not contain them. _ ' nis iB_»irt« j ^^_^^^ ^_^^^^^^^ Onioi 



page is now numberwl 

 and 2. -Ed.] 



;Tofo™ p«t TtThi f^^d volume. Compare N... I 



(he 



Dates aitd Hocbs for thb Stabs ei NoTJMBB.-These are «i follow. 

 Jt foTr n:::be.;-Oct. 30.at 10» o-cloek; Nov. 3 lOJo'cloc.; Nov. VOoa^ 

 Nov. 10. Oi o'clock ; Nov. U, H o'clock; Nov. 18, 9} o clock ; Nov. 2B, 9 o cUh± 

 Nov. 26. 81 o'clock ; Nov. S9, 8i o'elock ; and Dee. 3, «< »i ■"J""''- . 



Contents of Kkowledge ^o. 6 



P10«. 



Dreams. By Edward Clodd W 



IntelUgeneem AnimaU^ ^-^ "" 



Bohds, Liquids, and Gases.-Part 



IV. Hy W. Mattieu WiUiama .. 



Perspocti'vo Illusions. By H. J. 



Bla<-k. P.O. 8 ,,, 



Rkviews —British Ferns , ■ ■•• '" 

 Hiercglvphieal Inecription, of the 

 RakariVvramid,. By a Member of 

 the Society of Biblical Archn-olegy 111 

 CoRBRsro.vDKNCBr— ToOur Reader, 

 — Prof esoor Clerk Marwelland the 

 Reversibility of the Gramme Ma- 

 chinc-Sundav Art Eibibition— 



not- 



The Pyramid and Paradoiei»— 

 Pvram'id Measures— Possible DliJy 

 Variation of Pendulum Darinn • 

 Theory of Evolution- ProblOM 

 Geometrically Insoluble — A R«- 



eoroeincaiiy iu»v.»»~ - — 



jarkable Rainbow, ic _ "» 



The Southern Skies in December— 



(llluitratiJ) 



11» 



Q„„,<,, IM 



liephes to Qtiories }~ 



Our Mathematical Colomn »» 



Our Whist Column •" 



Our Ch.>M Column }" 



Answers to Correspondento »-" 



