April G, 1883.] 



KNOWLEDGE • 



201 



AN ILLJLSXRATED 



MAGAZINEOF^ENCE 



[ . PLAIN LTVf CRDED -lYACT Vi DESCRIBED /i 



LONDON: FBI J) AY, APRIL G, 1883. 



Contents op No. 75. 



FAGB. I TAOB. 



■Science unil Art Gossip 201 I Mr. Whistler's Etchings. (lUui.) 20S 



A Naturalist's Tear. X. The I Serials Kcceivcd 209 



Pt»rmii;.n. Bt Grant Allen 203 I Cokbkspokdbncb :— Stays and Fat 



Son Worship. By K. A. Proctor ... 2(H i —Saturn's Kings — Rotarion of 



"Our Bodies." IX. Absorption Planets — The Mnon's Vertex- 



and Blood Hepair. Bv Dr. A. The Hamiltonian System— Ketro- 



Wilson, F.R.S.E.. 4c. ." 204 cession of the Sea, ic 210 



Tricycles in H'*3. Bt John Brown- Our Mathematical Column 213 



ing, F.K.A.S : 205, Our Chess Column 213 



The Amateur Electrici«n. (Illut.) 206 Our Paradoi Comer: The Flat 



Periods of the Aurora 207 ' Earth Theory 2U 



^rinuf anil Sirt (go6£(ip. 



Parado.\ers have strange ways. We give in our Para- 

 dox Column (but, out of consideration for our readers, in 

 small type) the latest illustration of the ways of earth 

 flatteners. In answer to many inquiries and some com- 

 .plaints about the introduction of this particular paradox, 

 we may note that we agree with what Prof. De Morgan 

 said aViout that very paradox — that it would do good, by 

 setting many who accept the usual theory because it is the 

 usual theory, examining the reason of their belief. It also 

 serves to show how little reasoning power some human 

 beings possess. For instance, here is a theory which sets 

 the sun 900 mUes above a circular Hat surface about 

 6,000 miles in diameter ; and here are the zetetic folk, who 

 number, I dare say, a round dozen, if not a score, who 

 cannot see that if there is a point vertically above a cir- 

 cular plane and one-seventh above its diameter from that 

 |)lane, it must be in sight from every point in the plane. 



Then comes Dr. Collins Symons, with his little work of 

 200 pages, lauded by the Oxford Chronicle and Bucks and 

 Berks Gazelle, stating, and to his own satisfaction }>roving, 

 that Neptune is illuminated as brightly as the earth, or 

 Venus, or Mercury. I am abused in that paper because I 

 cannot make any believer in this preposterous theory 

 understand why no one who knows anything of science 

 accepts it, and scarce any one even thinks it worth while 

 to take the least notice of it. I am now pointedly asked 

 to name any ph}-sicist or astronomer except myself who 

 has written a word against the discovery : to wliich I 

 simply answer that I should be very much surprised to 

 hear of any. It was only the accident that, as Editor of 

 Knowledge, I received a question relating to it (probably 

 from l,)r. Symons himself), which led to my noticing it 

 myself. 



Onk of the odd blunders made in the 0. C. and B. and 

 B. G. (the believer in such an absurdity was bound to fall 

 into many odd blunders) suggests a pretty little problem 

 in mathematics. I said " the loss of light by atmospheric 

 absorption, in a room of ordinary size, is inappreciable," 



which is of course true. To tiiis the sir.gular reply is made 

 that Dr. Thomas Young pointed out that only one LV^OOt^' 

 part of the sun's light reaches us when he is on the horizon 

 and his beams pass through 200 miles of air. Rooms are 

 not usually 20U miles long, but that is a detail (as folk say 

 I say, though 1 have not said so, very often, in Knowledge). 

 Now the problem I suggest is this. Supposing 1,999- 

 i!,000ths of the sun's light lost in passing through 50 miles 

 of air of uniform density equal to that at the sea-level (on 

 the average), how much is lost in passing through a yard, 

 or five j'ards, or ten yards ? It would content the average 

 parado.xer, I fancy, to say that since there are 88,000 yards 

 in 50 miles, the loss would be 1 88,000 of l,999-2,000ths 

 in one yard, or roughly about a 90,000th — say one 10,000th 

 part as the utmost loss by absorption in a room nine yards 

 long. This of course would be utterly inappreciable, even 

 with the most delicate photometer — and I was writing 

 about ordinary eyesight. 



But it would be a shame to take advantage thus of the 

 ignorance of those who fancy Dr. Collins Symons has made 

 a great discovery — as indeed he has, only it is of the 

 mare's-nest order — so I give the correct solution of the 

 problem in the Mathematical Column. It will be seen 

 that the reduction in a yard of air is about nine times as 

 great as that above indicated — though still the absorption 

 even in ten or twenty yards would be inappreciable by 

 ordinary eyesight. 



Me. Hampden, the flattener of the earth, has been really 

 handsomely treated in these columns. When Knowledge 

 had been but recently started, he asked for permission to 

 air his preposterous views here ; and not receiving any 

 particular encouragement, wrote such letters as he is 

 accustomed to write, in which the changes were pleasingly 

 rung on the terms " liar," " coward," " scoundrel," and 

 " dastard," with correspondingly elegant adjectives. He 

 also threatened (and doubtless he carried out the threat) 

 to denounce the Editor of Knowledge to all who might 

 advertise in these pages. Yet, later on, we gave him space 

 (having, as we believe, established our position in the world 

 of serials) to describe and explain his views — in our Para- 

 dox Column. But he could not be persuaded to limit himself 

 to what was thus allowed him. Instead of describing his 

 own views, he simply maundered on, through page after 

 page of MS. about the accepted theories of the earth's form, 

 by which the commerce of the world is regulated, and which 

 is justly esteemed by those who can follow the researches 

 of Copernicus, Galileo, Kepler, and Newton. Asked to 

 explain a few difficulties which obviously exist in his 

 absurd theory, Mr. Hampden flies to simple abuse, the 

 natural resource of an advocate who has no case, nor skill 

 (as Parallax had) even to defend a bad case. He resumes 

 his appeals to those who advertise in Knowledge, as if any 

 true theory were ever established by libel ; calls us by all 

 the foul names which his singularly copious vocabulary 

 contains ; abuses Messrs. Wallace, Tyndall, Huxley, 

 Spencer, Sir Edm. Beckett, and a host of other eminent 

 men — by no means of the same school — and all this in 

 perfect safety, since he knows perfectly well that he is not 

 worth legal powder and shot. 



But Mr. Hampden represents those who smile at his 

 absurdities as opponents of religion. Verdant Green was 

 in the habit, Mr. Cuthbert Bede informs us, of modestly 

 attributing his verses, and especially his weaker verses, to 

 one William Shakespeare. Mr. .John Hampden goes con- 

 sideraVjly beyond that feeble O.xonian, for he assigns his 

 theory, assuredly the most absurd that has ever presented 



