38 



♦ KNOWLEDGE . 



[Jan. 9, lSt-5 



consideration that it became known to mankind half a century ago, 

 if it is only now that for the first time I am benefited by it. Bat, 

 if I pique myself on knowing every new thing that comes out, at least 

 as soon as any one else, I am reasonably offended at having any- 

 thing presented to my notice as new which I have known, tried, 

 and, perhaps, discarded years ago. 



la not the "Ideal" lamp, which was noticed so favourably in 

 your "Inventor's Column," the same, to all intents and purposes, 

 if not identically, as the one of which I here annex a figure, which 

 represents a lamp now on my tabic, where it has served its pur- 

 pose, on and off, for some three years 'i I also gi%'e below it the 

 figure of the so-called '■ Ideal" lamp, which is obviously a faithful 

 copy — exact in outline and shading, differing only in the sharpness 

 of impression. Surely it verges on the absurd to offer the " Ideal" 

 lamp as a lifif invention. — I am, yours faithfully, J. Hesschel. 



Collingwood, Dec. 22. 



[Colonel Herschel appends to his letter two woodcuts, one repre- 

 senting the "Empress" lamp, and the other the "Ideal" one. 

 They are, as he says, absolute facsimiles, the one being seemingly 

 printed from a cliche of tbe woodblock of the other. — Ed.] 



A .SELF-LIGHTIXG GAS-BCRNEK. 



[15-58] — I was amused to sec in your ''Inventor's Column," of 

 Dec. 2G, an item re " A Self-Lighting Gas-burner and Tap." The 

 idea is far from new, and is nlso unnecessarily complicated. The 

 same object would be achieved by the very simple device of making 

 the usual tap so that it could not be entirely turned off, and thus 

 leave a minute light always burning. This plan obviates the 

 necessity fur a second burner of any kind. 



Tears ago I had such a burner and tap as you describe from a 

 Mr. Weston, of this town, who had patented it. I found it to 

 answer very well, except that the small light was liable to be blown 

 out, which, of course, was fatal to its use. The patentee then made 

 a rather ingenious sheath or cap to protect the small light ; but, in 

 the meantime, I had taken out the plug of an ordinary gas-tap, and 

 in three minutes I filed a small channel round it, so that it let a 

 little gas escape when the tap was turned off, and hey, presto I I 

 had the " very thing." I have had this tap and burner burning in 

 my bedroom now for a number of years, and, being protected by a 

 globe, it has never once been blown out. It answers every pur- 

 pose; we have only to turn the tap "on" to have a light; and 

 when it is turned " off," sufiicient gas still comes through to 

 maintain a small and invisible light, costing, as near as I can 

 estimate, about one penny per month. I have 3Ir. Weston's 

 " improved" invention still in use in the cellar, but, in spite of its 

 protective cap, it has been out several times (filling the cellar with 

 gas) ; and another objection to it is, that the small light in time 

 enlarges its orifice and allows too much gas to come through. I 

 believe Mr. W. has remedied this objection also, but, as my simple 

 plan leaves nothing to be desired, I have not tried his last 

 improvement. WiLlUM PitKAKD. 



Sheffield. 



MATTER. 



[1550j— Mr. F. Routledge, letter 1513, asks what basis can there 

 be for the statement of Hceckel on atoms having an unalterable 

 nature, &c. I reply, the answer is contained in his own letter, viz., 

 " it is an inference which he (Haeckel) thinks it fair to make from 

 his experiments." I quite agree with Mr. Routledge that the mere 

 statement of authority, although he be the Pope claiming infalli- 

 bility, has not any claim upon our belief, unless the statement be 

 in accordance with reason and logic. But Mr. Routledge goes too 

 far ; he asks us to accept his ip.<c dixit, instead of Haickel's state- 

 ment derived from experimental experience. 



Mr. Routledge quotes Professor Clifford's " Ethics of Belief," to 

 prove what ? That Hteckel's opinion on atoms is an error of 

 judgment ? Xo I Hence I ask, how docs Professor Clifford's 

 authority apply ? 



It is conceivable to Haeckel, and to myself also, that attraction 

 and repulsion are concomitants of pleasure and displeasure. lam 

 attracted to things I like, or derive pleasure from ; is it then un- 

 reasonable to conclade that like causes act in atoms ? That like 

 effects are produced by like causes ; that atoms, even if uncon- 

 sciously, like each other, and are thereby attracted ; or dislike each 

 other, and are thereby repulsed? In conclusion, "the fear of 

 consequences" onght not to enter the field of honest research; 

 let us have the truth — it is our Haven of Rest. F. W. H. 



[There is a verbal ambiguity in the word "attracted," as used 

 by " F. \V. H.," which materially impairs the force of his argu- 

 ment. To say that a man being "attracted" by a beautiful object 



is an analogoua thing to a needle being " attracted " by a magnet, 

 is to be guiltv of the Fallacia equirocationis of the Schoolmen. — 



Ed.] 



THE CARXIVUROUS PARROT OF NEW ZEALAND. 



[15G0] — Your readers will perhaps be interested to read the 

 following extraordinary action of a New Zealand species of iiarrot 

 called a Kia. "While engaged in laying out the survey for a line of 

 railway in the mountains at Arthur's Pass, one evening, the men 

 set out to return to their camp, taking a track over the mountain 

 instead of through the dense bush. They were followed by a very 

 handsome jet-black sheep-dog, belonging to one of the men. The 

 dog, having lagged behind, was presently heard yelping and 

 barking, and the owner went back to assist, thinking it might have 

 fallen among the rocks and hurt itself, but it soon came up to him, 

 carrying in its mouth a mangled kia, and then the dog was found 

 to be severely torn and pecked on the loin. The parrot had evidently 

 swooped down on the dog and commenced its depredation, as the 

 kias are accustomed to do to the sheep with invariably fatal result, 

 but the dog, after recovering from its surprise, must soon have 

 succeeded in getting hold of the bird. This species of parrot keeps 

 to the higher parts of the mountains, mostly near the snow-line. Jc 

 has lately become a terror to shepherds from the numbers of 

 sheep it kills, by tearing open a hole in the loins and eating 

 the kidney fat. Of late the sea-gull has joined the parrots in 

 killing Iambs and sheep, and we hear that even horses are occa- 

 tionally killed by sea-gulls when found helpless in the snow. The 

 Kia is the only parrot I ever heard of that attacks a living animal ^ 

 but it is observed that all New Zealand wild birds, including the 

 handsome little parrakeets, have a propensity for eating raw meat, 

 greatly preferring the gut. I have seen the carcase of a sheep 

 hung up to a branch at a diggers' camp so covered with parrakeets, 

 robins, bush canaries, and fantails, that nothing of the carcase 

 conld be seen except the legs and hoofs. C. N. Bell. 



Christchurch, X.Z. 



^See Knowledge, Vol. I., pp. 381 and 471. — Ed.] 



LETTERS RECEIVED AND SHORT ANSWERS. 



F. T. B. I think that if you will consult any of our contem- 

 poraries who give reviews of books, you will find that the appending 

 of prices of works to the literary notices of them is never practised. 

 To introduce such an innovation might be to supply certain readers 

 of K.NOWLEDGE " with as much information as they require," while 

 others might wish to know the size, number of pages, and style of 

 binding or covering of the volume noticed, and so on. The more 

 the merely commercial element is dissociated from criticism, the 

 more likely is such criticism to be honest and unbiassed. The 

 object of every one who writes notices of books in these 

 columns is, I verily hope and believe, to give an absolutely 

 impartial opinion of their contents ; in entire disregart} 

 whether such opinion makes or mars the sale of the work 

 under review. — Jos. M. Lnminons paint is made for out-door 

 use, and is then mixed, I believe, with some oil medium. That 

 sold in small bottles, which is, as you say, mixed with warn> 

 water, is for experiments indoors. Carriage-gates, itc, hav£> 

 been painted with the oil-paint, and have stood, I understand, 

 very well. — Geo. H.iiLEY. Will be dealt with in Article 

 XVIII. on "Electro-plating." Please see paragraph, in capita! 

 letters, which concludes the heading of the Correspondence 

 Columns. — W. M. Siureock. Could you furnish a very short; 

 precis of facts ? — J. Faeear. I cannot describe the photo- 

 phone at length here ; and can only say that it is ai> 

 extraordinarily ingenious piece of apparatus for transmitting 

 sounds through the mediate action of light on the curious metal 

 Selenium. I am ignorant of the meaning of the word " Karoo." — 

 TnoM.^s Foster. 7/ the printing of the letter of " H. L." in the 

 same type as the articles on p. 439 of our last volume did mislead 

 any one into the belief that your series of essays were in any 

 sense whatever intended as a reply to that writer, I quite feel 

 that I should apologise to you. It never, however, occurred to 

 me then — and I am very loth to believe now — that the mere fact 

 of the difference of type in a communication so obviously taking 

 the form of a letter was calculated either to originate or foster 

 such a delusion. — Hugh Clements. Thanks: but enough has 

 already appeared about your "' Weather Cycle" in these columns. 

 E. D. Girdle.stone. As there is no more familiar fact in optics 

 than that the colours of objects have their origin in the absorption 

 of certain rays of the spectrum and the reflection of the remainder, 

 I rather fail to perceive precisely what you are driving at. See Sir 

 John Herschel's " Familiar Lectures on Scientific Subjects." — R. T. 

 Shea. The best book on the suljject is Davies's " Preparation aj.d 



