Oct. 31, 1884.] 



KNOWLEDGE . 



373 



mynas, parrots, aud starlings, which are social birds, all fly fast, 

 and by cleaving — they never soar. 



The wagtails have a jerky, cleaving flight, as if -they were always 

 winding up for a fresh exertion ; it consists of dips and rises. 



That singular bird the Darter or Snake bird {I'lotus anhir)ga(?)), 

 quite at home in the water, is equally at sea on the wing, flying 

 clumsily and laboriously, and resting repeatedly in soars. Our 

 egrets, as a rule, fly leisurely, with steady flap, but 1 have seen 

 flights of them adopting the soar as well, as if the exception ran in 

 families. 



Dragon-flies flap and soar, the former when on the feed, and the 

 latter when sunning themselves. Flying-fish both soar and flap; 

 pea and guinea fowl flap awkwardly in rising, and soar on alight- 

 ing; white ants flap in swarming. Bnt some birds, strange to say, 

 eeem to progress by soaring, i.e., apparently irrespective of 

 momentum, and this power is exhibited in these in an astonishing 

 manner. Take any one of the many instances I can adduce, and 

 iAye phenomenon is equally marvellous. 



A bright, cold-weather day, and a cobalt sky above you, and 

 perhaps half a mile up in the ca^rulean, you see a couple of adju- 

 tants and half a dozen condors and vultures soaring, their keen 

 eyes the while watching the earth. Watch the adjutant. Having 

 lost his momentum he flaps his enormous wings once or twice and 

 then treats you to circles and circles of soar, apparently endless, 

 until you marvel whence his power comes. And so with his 

 companion condors and vultures. 



On one occasion I was travelling eastward by rail, and noticed 

 ;in adjutant soaring towards the line, and half a mile off on my 

 left, when he had crossed above, and I again looked out on my 

 right, he was still soaring, and certainly had not flapped in the 

 interval. What is this wonderful power ? It is difficult to believe 

 that a mile soar is the momentum of one or two flaps of powerful 

 wings. It may be so, for on riuod ice you may momentumise a mile 

 with a few good fla])S, so to speak, of your skate-clad feet, and 

 that, too, in the face of friction. 



Then, too, these soarers have a less 'dense resisting medium at 

 their favourite heights, and so a powerful flap gives a prolonged 

 momentum. The poisers are very wonderful in their action, and 

 are best illustrated by the kingfishers ; the adjutants overcome 

 gravity by soaring ; another vastly smaller and weaker bird do so 

 by poising, which consists of a stationary position, secured by 

 rapid and invisible flutter-flapping, the points of the wings being 

 directed upwards. The extraordinary thing is that, with this 

 immense display of muscular power, they should remain absolutely 

 stationary until the plunge; so stationary that you can cover the 

 kingfisher with your gun for a minute or more. Another wonderful 

 thing is its power of instantly overcoming momentum ; thus, 

 baffled in the plunge, the kingfisher will take two or three bounds 

 in flight, and tlwn instantig jioi.s(> exactly at the right clerafion. 

 Toms poise, but not so steadily and persistently as the kingfishers, 

 nor with the same muscular action. 



Other poisers are the sun-birds and moths, while probing flowers 

 for honey, but their movements arc not so) striking as those of the 

 kingfishers. R. F. H. 



LETTEKS RECEIVED AND SHOET ANSWERS. 



Ghost of a Lhtle Boy. Such a slip as that of — 5 hours for 

 + 5 hours in no sense invalidates the argument of "C. R.," that for 

 a ghost to appear at the instant of the death of its owner it must 

 do so at a different hour in America to that at which such owner 

 gave it up in England. — A. R. Paxn'ett. The British Association 

 Catalogue has been for years out of print, and is only procurable at 

 a very high price indeed. Jlr. Wesley, of Essex-street, Strand, 

 London, would be the likeliest man to procure you a copy. I do 

 uot know where "Jliidler's Comet Catalogue" is to be had, but 

 there is a very good one in Chambers's " Descriptive Astronomy." 

 — G. PixxixGTO.x (23, Chichester-street, Chester) should forthwith 

 aiake the acquaintance of J. Murray (of Newcastle), and exchange 

 views with him. " Pompey and Caesar am berry much alike, 'spe- 

 cially Pompey." — Miss tie Jersey Moore. The conductor of this 

 journal is so dunned for his autograph that he has been reluctantly 

 compelled to make a rule to refuse it ; and regrets, extremely, that 

 lie can make no exception in your particular case. — J. B. Do 

 you seriously suppose that the conductor of Knowledge would 

 suffer his name to appear continually were it not true ? — 

 J. McLagax. " Physical science " is such an extremely compre- 

 hensive term that the only reply I can give to your query is the 

 form in which it appears is : All. Lyell's " Students Elements of 

 Geology" ought to suit you for the purely geological part of your 

 subject, which, though, is now made a very heterogeneous one. — 

 n. C. Halle. Tide letter by B.M., F.R.C.S.— William Ruxiz. 

 I am wholly unable to help you. I have never heard of the person 



yon name publishing anything bnt the grossest and most scurrilous 

 abuse. See concluding paragraph (in capital letters) at the head 

 of the correspondence columns. — F. H. " Better late than never " 

 sends the seventieth or eightieth answer received to Mr. Bidder's 

 Figure Puzzle. — S. E. TnoEXTox. The best college in which you 

 can studj' to become an Electrical Engineer is the School of Sub- 

 marine 'Telegraphy and Electrical Engineering, 12, Prince's-street, 

 Ilanover-square, W. — William Millar. We need not trouble Mr. 

 Mattieu Williams. It is merely a form of puffing advertisement. The 

 moon -was in her descending node at the time of the recent eclipse. — 

 Veritas. I cannot undertake to answer questions which should be 

 submitted to a solicitor. Law can only find a place in these 

 columns in its aspect of a branch of sociology. — Fleming, Wilsox, 

 & Co. Mr. Ganga Rani's pamphlet was reviewed on p. 75 of the 

 current volume of Knowlebge. — Some Anontmous Correspondent 

 sends me two religious rhymes utterly inappropriate to these 

 columns, either for insertion or review. — J. Luky asks Mr. Browning 

 to describe the various two-speed tricycle gears now in use, with 

 their weight, mode of fixing, Ac. He also seeks a definition of " a 

 steep hill," as understood in the Eastern Counties. — J. O'Neill. 

 Thanks. It will be utilised. — J. P. B. I know of no single cheap 

 Encyclopedia of the comprehensive character you require. Nichols' 

 " Cyclopaedia of the Physical Sciences " is an excellent book of refer- 

 ence in a small compass, and 1 have some idea that its publishers 

 also issued a corresponding one of the Natural Sciences. Maunder's 

 " Treasury of Knowledge " contains a Gazetteer, a precis of his- 

 tory, and a mass of other information. Perhaps, though, your best 

 plan would be to try and get a second-hand copy of the old " Penny 

 Cyclopaedia." It is a perfect repertory of information, although 

 the Physics are not quite up to date. — Maximilian Strong. Out 

 Lord was undoubtedly bom four years before the " Anno Domini " 

 of the calendar. Suetonius says that Tiberius was born 42 K.v. ; 

 and, as he was 54 when he became emperor, his reign must have 

 commenced A.n. 12. — Ferr.^rius. Tour quotation is from Pope's 

 " Essay on Criticism." "Pierian" was an expression applied to 

 the Muses, &c., from Pieria, a tract of country in Thessaly. — W. 

 Stringfield. Dr. Gerber's book was sent to us for notice by the 

 Messrs. Triibner, whose name was printed on the title-page, whence 

 the Reviewer copied it. — L. P. asks if any of our readers have 

 tried the Hamiltonian method, and, if so, with what results ? — 

 Henry Morley. You can no more multiply a sum of money into 

 itself than yon can trees by trees, or paragraphs by chimney-pots. 

 — W. H. K. S. You are confusing in a very odd way " a refusal 

 to consider evidence" with wilful unbelief. A man ignorant of 

 evidence cannot be said, in any legitimate sense, to have any belief 

 at all. What is meant is this. The object before me possesses the 

 attributes of whiteness, flexibility, semi-transparency, and so on, 

 and the sum of these I call a sheet of paper. Suppose now that 

 you were to tell me that my salvation depended on my belief 

 that it was really (say) a roast goose. If this were so, my 

 damnation must be inevitable ; and yet this is scarcely 

 an exaggeration of what is often described from the pulpit as 

 " wilful imbecility." — W. Received. — C. Carus-Wilson. I regret 

 the blunder, for the rectification of which steps have been taken. 

 — E. W. Young protests against the Tulgarism of " don't " being 

 used for '* doesn't," iu connection with a singular nominative. — T. 

 Harrisox. " Fontenelle " will be continued. I condole with j-ou 

 sincerely on having to Usten to such stuff as that of which you 

 send the report. The person you refer to will get no more unpaid 

 advertisements in these columns. — C. Hunter. I regret my 

 inability to supply Knowledge to your League gratis. If I began 

 by doing so there are numerous associations throughout the king- 

 dom who might equally claim to receive it for nothing. — J. M. 

 Coates. As yours is one of several requests for a description of 

 a graphical method of predicting a Lunar Eclipse, one shall 

 appear in due course. — Dr. Davey. Your book shall receive atten- 

 tion. — Thos. Radmore. Thanks for your friendly letter. I shall 

 always be glad of any original observations of interest. — Thos. 

 Baugh. Certainly uot. How could the subject himself, or any 

 spectator (real or imaginary) be examined or cross-examined ? 

 Science cannot possibly deal with such a case. — W. S. C. I should 

 scarcely think that a patent is now in existence for the mere use 

 of asbestos in a gas fire. Gas fires are no* " all unhealthy." — 

 C. H. Kesteven. Doubtless the fish decomposed from radiation 

 and moisture. — A. M. D. I have never iu my life heard either of 

 the man or of his " philosophy." — Nemesis. Shall receive imme- 

 diate attention. 



WHIST. — J. E. BucKBARRow. You appear to refer to (what I 

 imagined was as dead as Queen Anne) Long Whist. With regard 

 to the question you raise, the law was explicit : " Honours can only 

 be called at eight points, and then only by the player whose turn it 

 is to play." The fact of his adversaries standing at nine points 

 does not affect this rule, one way or the other. 



