Mat 4, 1883.] 



• KNOWLEDGE • 



269 



fi-ront appearance according to its surrouodings : or, more coarsely, 

 to the way in which tepid water api^ears hot or cold to a hand 

 placed ia it after being in coM or hot wator respectively. — U. 1'.] 



THE DIVIDED SKIUT. 



[»09] — I haTc read the letter on the new skirt by " A Lady," in 

 Knowlkdce, April 13, and I think the description may prejudice 

 many against this valuable garment. 



The only similarity to gentlemen's trousers is the division. Each 

 leg is one yard in circumference, and the whole is loose and com- 

 fortable. The appearance of mine is so like a petticoat that in 

 raising the dress the difference is imperceptible. 



I have given a pattern, in three sizes, with instructions, to Miss 

 M. Knight, High-street, Maldon, Essex; and she is prepared to 

 supply them to any one on receipt of a Postal Order for One Shilling. 

 A Member of the L. S. A. 



[The aathor of the article referred to informs us that many 

 ladies prefer the divided skirt as she described it, and even less 

 • full " (whatever that may mean) ; but that, even as described by 

 her, the ap|>earance is like a petticoat when the dress is raised, as 

 ir: stepping into a carriage. Quite a number of correspondents, by 

 the way, seem to imagine that the skirt of the dress is divided. One 

 even asks if we could not publish a photograph of " A Lady " to 

 show what the divided skirt is like, which, of course, would be 

 <|uite out of the question, even though it would show the divided 

 skirt. The mistake about the skirt probably arises from the 

 pu-tures which have appeared in Piincli and other comic papers, 

 showing a divided dress. The divided skirt is entirely concealed 

 by the skirt of the dress, which is not divided at all. I am requested 

 to note that for tricycling the divided skirt is better without the 

 plaits, which are apt to catch as the feet pass each other. — R. P.] 



ilK: 



IXTEHPLAXETARY .ETHER. 



[810] — With reference to G. M.'s letter on the rotation of planets 

 (No. 770, p. 210) and ytmr footnote thereon, will not the hyjiothe- 

 tical ether, if such a substance there be, have some effect in acting 

 •• a *' break " on the rotation of planets, and likewise as a resisting 

 force on their circuits round the sun Y I suppose it is now pretty 

 well established that some such substance must pervade, space 

 acting as a link of intercommunication between the widely-scattered 

 puta of the material universe. It is evident that there must be 

 aome medium of communication, as the waves of light cannot be 

 propagated through a void, but must have some material pathway. 

 Snch a substance must also offer a resisting medium to the passage 

 of the heavenly bodies through space, and, given sufficient time. 

 Bast ultimately bring them to rest, unless their initi.il f<irce is re- 

 newed from without. Granting this resisting medium, it is clear 

 that the gravitating force of the sun will eventually overcome the 

 centrifugal tendency of the planets, and draw them one after 

 •DOther into it. I will be glad to hear what science has to say on 

 tkig point, and whether any evidence of snch a resisting medium 

 Iiaa been obsen-ed. " W. U. 



[We infer the extreme, the practically infinite, tenuity of inter- 

 planetary matter, from the fact that neither rotation nor revolution 

 is appreciably affected by it.— K. P.] 



ANIMAL IX.STINCTS.— A WKAXGLER'S PUZZLK. 



[811] — George J. Romanes, Esq., in a lecture delivered in the 

 Hnlme Town-hall, Manchester, March 1879, said, in referring to 

 animal instincts, that there were satisfactory reasons for con- 

 dnding that most animal instincts were the outcome of a natural 

 growth, and that the few outstanding cases which were not capable 

 «rf explanation (at that time) in this way ought to be considered as 

 objects for further scientific inquiry, and not to be set down as 

 npematural, and, therefore, beyond the scope of such incjiiiry. 

 The instincts not susceptible of explanation in this way were enu- 

 ■Jerated by him to be (1) the migratory instinct, (2) the so-called 

 "homing" instinct, and (3) the instinct manifested by certain 

 waap-like insects. " These insects," he said, " lay up a store of 

 ■pWers as food for their larvae when the latter leave the egg. To 

 4> this they stiog the spiders in a certain spot of the body where 

 Aere is a large nerve-centre, the effect being that the spider is not 

 killed outright, but merely parahsed, and so does not decomjiose 

 during its imprisonment, and while the eggs of the wasp are in the 

 process of hatching." 



Perhaps some of yonr biological, readers may be able to say 

 whether further " sciontitic inquiry " has bpen made, and with 

 what results. 



I have seen no answers to " A Wrangler's " questions (No. 70, 

 1^ 138). In reference to (1), if the man threw some object (say 



his cap) away from his body, would not the reaction dislodge him ? 

 I could not answer for him escaping without bodily injury. 



U. ASKKH. 

 [That would do ; but if he had no such object to throw, blowing 

 would do : he would slide off, and have to take bis chance as to the 

 sequent fall. — R. P.] 



A DISCOUNT DODGK. 

 [812]— The multiplication "dodge," given by Mr. Green (750, 

 p. 1G8), brought to my memory a discount "dodge," of which a 

 friend of mine was wont to make use, and which I never saw used 

 before, nor referred to in any arithmetic. I dare say my friend 

 found it in some book, but I never questioned him on this point, 

 and cannot do so now, seeing that he, poor fellow, gave over 

 figuring on this earth some six or seven months ago. To find out 

 the discount on any sura at the rate of 2J per cent, or 5 per cent, 

 is easy enough, without the aid either of figures or an interest 

 table; but, to find out the discount on a given sum, at such rates 

 as 3J per cent., 3j per cent.. U jier cent., lic, is not so easy. My 

 friend's plan was to multiply the principal sum by double the rate 

 of discount, the product, after cutting off the right-hand figures, 

 showing the amount of the discount in shillings — thus, supposing 

 an invoice amounting to £132. 15s. had to be subjected to a discount 

 of 3J percent., the operation of calculating the same, according 

 to the long way and the short way, would be as shown below : — 



Lon? Wav. 132 15 

 3i 



LETTERS RECEIVED. 



More Light. All right. — J. G. JonNSON. Hope to lecture there 

 and elsewhere soon. — No Name, bit No Malice. No sense and no 

 manners. — G. F. The phenomenon was a paraselene — not very 

 common, but well known. — G. F. M. Thanks. — a Centaitri. Im- 

 possible to answer yon here. — Naturalist. An old joke, but good. 

 — Attentive Re.mier of "Knowledge." Questions forivarded. — 

 J. MuNRO. Quite natural. But then yon see those paragraphs, Ac, 

 which you do not care for were written in response to the wishes of 

 others who take a different view. I do not tell you to cease to read 

 Knowledoe, but can you not leave out those paragraphs here and 

 there which you do not care for, remembering that tastes differ? — 

 John Gree.nfiei.h. How many times your annual subscription 

 would pay, do you suppose, for such a letter as yours ? Try this 

 little sum. Are jou, by any chance, one of " the great men," uU 

 of whom yon say " I have offended, and consequently no one will 

 write for me " ? Now, before you retire in dudgeon and discontent 

 (bnt very much to my content), learn that I am not aware of having 

 offended a single "great man." Nine-tenths of those whom I have 

 invited to write here have done so, and are likely to continue. You 

 mnst not think that because I declined to give admission to certain 

 wild theories of your own, I have offended all the rest of " the 

 great men." As for " resigning," to whom should I resign ? To 

 the proprietor of K.\owLi!DGE ? Very well. The Editor of Know- 

 ledge hereby offers his resignation to the proprietor; and the pro- 

 prietor of Knowledge hereby declines to accept the Editor's resig- 

 nation. — Hen'BY Li"pton. Consider that I raise my hat to you in 

 token of adieu, and pass on. (Little space wasted here, any way.) 

 — C. T. Highgate. Omittance is no quittance. — H. C. Swan. Doubt 

 if Dr. Wilson would gravely reply to any advocate of the old phre- 

 nology. — C. P. L. B. Do not know of any work on the miocene 

 formation, and especially on the Savalik Hills of India ; but perhaps 

 some correspondent of Kxo«xe1)GE may be able to tell us of one. 



