Oct. 5, 1883.] 



♦ KNOV\^LEDGE ♦ 



219 



" Let Knowledge gi-ow from more to more." — Alfeed Tennyson. 



Only a small proportion of Letters received can possibly he in- 

 serted. Corresponde-xts must not be offended, therefore, should their 

 letters not appear. 



All Editorial communications should be addressed to the Editor of 

 Knowledge; all Business communications to the Publishers, at the 

 Office, 74, Oreat Queen-street, W.C. If this is not attended to 



DELAYS arise FOR WHICH THE EDITOR IS NOT RESPONSIBLE. 



All Remittances, Cheques, and Post Office Orders should be made 

 payable to Messes. Wyman & Sons. 



The Editor is not responsible for the opinions of correspondents. 



No commonications are answered bt post, even thoogh stamped 

 and directed envelope be enclosed. 



SIE WILLIAM HERSCHEL. 



[947] — I shall feel obliged if your contributor " A Fellow of the 

 Royal Astronomical Society" — the one, I mean, who wrote "The 

 Sun in a Three-inch Telescope " — will communicate his authority 

 for the statement that " Sir William Hershel lost an eye " in an 

 attempt to look at the sun without suitable protection. It may be 

 true ; but to the best of my recollection I never heard of it before. 



Collingwood, Sept. 28, 1883. J. Herschel. 



ASTRONOMY OP THE TIMES. 



[948] — The Times of September 22nd, in its leader on Professor 

 Ball's address to the British Association, informs us, in reference to 

 the Earth's Orbit, that " the distance that separates ua from the 

 sun is variable, being greatest when our planet is on the major axis, 

 smallest when it is on the minor axis of the ellipse," so that, putting 

 a for the semi-major axis of the earth's orbit, and c for the 

 eccentricity (when, of course. e<l) we must infer from the Times 

 that 



a (1 — e) > avl — e'-, 

 and therefore, that 



^/l^e > \^T+~e. 

 which is, &c. J. R. C. 



CURIOUS PHENOMENON. 



[949] — In your number of September 14 last, page 173, is an 

 account of a curious phenomenon, which is illustrated by an en- 

 graving. 



This evening, Sept. 21, at 8.30 p.m., I observed just such a 

 phenomenon also in the E.N.E., about 20° above the horizon. 



Tlio sky was cloudy at the time, and in the very words of the 

 article mentioned, '* For a moment I imagined that I was view- 

 ing the apparition of a new and glorious comet," the light was too 

 white to have an artificial terrestrial origin ; it remained well in 

 view for five minutes, but before I could bring a telescope to bear 

 upon it, it slowly faded. Mrs. Harbin. 



Preston Hoase, Yeovil. 



THE "SUN AND PLANET" BICYCLE. 



[950] — There aro two misprints in my letter (942). In line 9, 

 the word " seat " should be " feet " ;'and about " Sigma," I said that 

 lie seemed to have «o idea that Mr. Browning spoke of geared-vp 

 wheels. 



As to appearance, I should think a man looked better on a small, 

 neat machine than inside such a squirrel-cage as a GO-incli " Otto." 



S. J. 



HULL-DOWN SHIP. 



[951] — Your interesting articles called "Pretty Proofs of 

 the Earth's Rotundity" have caused mo to take a new interest 

 in the visible sea-horizon, and I have been observing it while 

 on the south coast recently with a 3i-incli telescope, of the 

 kind recommended in Knowledge. But a phonomeaon I do not 



understand at all has presented itself : to a ship, hull-down there 

 have seemed to be two horizons, a nearer one clear and distinct, on 

 which the rise and fall of the waves could be seen, and a farther 



one which really concealed the ship and gave it the appearance of 

 floating in the air ; and still more oddly a kind of reflection of the 

 ship's sails connected the more distant with the nearer horizon, 

 something as in this sketch, which I hope you can make out. Is 

 this usual ? Would you kindly explain it for the benefit of myself 

 and a few friends who saw but could not understand it, and you 

 will greatly oblige H.A.L.S. 



[Doubtless there was a layer of still air above the distant water 

 surface, of density greater than that of layer of air next above it ; 

 and the ship was reflected in that as in a horizontal mirror. R. P.] 



TOTEMISM. 



[952]— Mr. Edward Clodd, in the fifteenth chapter of his in- 

 teresting series of articles on " The Birth and Growth of Myth," 

 touches on the customs and prohibitions which totemism has 

 imposed upon savage and barbaric peoples ; he quotes as instances 

 the American-Indians and Australian tribes. He also speaks of a 

 form of salutation common to a certain province in China, but he 

 has omitted to notice a singular custom of the same type which 

 prevails in the native States of Cochin and Travancore in the 

 Southern part of the Indian peninsula. 



These States cannot be styled savage or barbaric. One-third of 

 the whole native population is Christian ; of the native castes, the 

 so-called Namburi Brahmins rank first ; after them come the Nairs. 

 It is of these we would speak. The rulers of these States are them- 

 selves of Nair descent. When they succeed to the throne they are 

 made Brahmins. They are "new-born" by passing through a 

 golden cow, or vessel of that metal, which then becomes the pro- 

 perty of the Brahmin priests. 



The females of the Royal families in these States invariably 

 marry Brahmins, but all Nair women have the privilege of 

 choosing their own husbands; bylaw they may change them as 

 often as they will, but this, it is said, is going out of fashion. 



Obviously, this custom led to great confusion in the matter of 

 inheritance ; therefore amongst the Nair caste a man's heirs are 

 not his own children— his property descends to the children of his 

 sisters or of his female cousins, however remote. 



With regard to polyandry, wo think it will generally be found to 

 exist in mountainous districts, and where the soil is very poor and 

 can only support a very small population. Snch, at least, are the 

 conditions in Ladakh, or Western Thibet, where this custom pre- 

 vails. Certain lOuropeans, who closely watched them for some 

 years with that object, could never discover that its inhabitants 

 practised infanticide. Co.smopolitan. 



LETTERS RECEIVED AND SHORT ANSWERS. 



E. D. Giroleston'e. — Imprimis, let me remark that I only object 

 to the waste of time over the study of formal logic, especially by 

 those who aro capable of reasoning correctly. I would not in the 

 slightest degree object to your studying logic. And now to your 

 illogical defence of Jack Ketch. You "argue correctly enough about 

 a suppositious Jack Ketch, who never existed save in your imagi- 

 nation. If the legislature had to select an executioner from among 



