March 3, 1882.] 



KNOWLEDGE 



389 



decennial periods from twenty to sixty. . . . Whilst the brain- 

 weight ia nearly 10 per cent, less in the female than in the male, 

 the statirre is only 8 per cent, less ; " [and, therefore, the weight 

 about 23 per cent.'less.— Ed.]— E. D. G. 



CATS AND DOGS.— SCIENCE AND RELIGION. 



[305] — A kitten, just weaned, was presented, a few years ago, to 

 « near relative of mine, who already had in his house a little 

 Maltese terrier bitch which had never had any puppies, and was 

 not in the way to have any. Well, imagine our surprise when this 

 little bitch at once began to suckle the kitten, and continued to do 

 ao, to my knowledge, for weeks, showing all the time an affection 

 amounting to jealousy for the kitten. The suckling repeatedly 

 went on upon my own lap, so in this case 1 will venture to state the 

 fact positively. 



Mav I support your own admirable resolves and dicta on this 

 subject by the following e.tcerpt from the " Life of C. Kingsley." 

 ii.iar the end of vol. ii. ; — " When a friend remarked that Darwin's 



il:ination of certain geological phenomena would hardly be con- 

 red orthorlox,' Charles Kingsley observed; — ' My friend, 

 I, lis orthodoxy is Truth; if Darwin speaks the truth, he is 

 jrlliodox.' " E. D. G. 



PARTIAL LOSS OF SPEECH. 



306]— Reading your article in No. 14 of Knowledge on 

 Brain Troubles," has brought to my mind a very interesting 

 instance of the total loss of speech under mental excitement, men- 

 tioned by Darwin in his '• Expression of the Emotions," lic, (chap, 

 liii., p. 324) : — •• A small dinner-party was given in honour of an 

 extremely shy man, who, when he rose to return thanks, rehearsed 

 the speech, which he had evidently learnt by heart, in absolute 

 silence, and did not utter a single word, but he acted as if he were 

 speaking with much emphasis. His friends, perceiving how the 

 case stood, loudly applauded the imaginary bursts of eloquence 

 whenever his gestures indicated a pause, and the man never dis- 

 covered that he had remained the whole time completely silent. On 

 the contrary, he afterwards remarked to my friend, with much satis- 

 biotion, that he thought he had succeeded uncommonly well." 



AETHrR Reeve. 



OPTICAL ILLUSIONS. 



.307] — The following is an illusion which, I think, has not yet 

 i;ii)eared in Knowledge : 



ABO 



The distance from 4 to B appears to be greater than that from 

 B to C, although thev sire in reality both exactly equal. — Yours. Ac, 



F. W. G. 



[308] — Take a sheet of penny stamps (one stamp vrill show it, 

 bat not so plainly as many), and look at the elUpse enclosing the 

 Queen's head, on which are written the words " Postage and Inland 

 Eevenuc." This ellipse appears of the form of a slightly elongated 

 octagon. I see it plainer by averted vision. — Yours, Ac, 



R. A. Law. 



DURATION OF LIFE. 



[309] — How does Mr. Allison mean that it " depends on our- 

 selves, in a great measure, whether we die at 35 or 75 years," when 

 •peaking of such fatal diseases as cancer, in his article under the 

 above heading in Knowledge, page 228 ? S. 



OPIUM— BACILLI— MICROSCOPICAL. 



[310] — If " Young Pill-Box" will study the peristaltic action of 

 the intestines in some standard physiological text-book, he will 

 f rrily find the explanation he seeks. In lead-poisoning, one of the 

 prominent symptoms is colic, i.e., spasmodic contraction of different 

 parts of the digestive canal. Opium (and, better still, belladonna), 

 by removing contraction, relieves the constipation. Opium is 

 also of great service in constipation from obstruction for a similar 

 reason. 



Would any of your readers kindly inform me where to find the 

 most recent information anent Bacilli and their kindred ? I mean 

 from a natural history point of view. Most of the Botanical text- 

 books pass very Ughtly over this group. I wish to study the subject 

 from every point of view. As your readers are well aware, these 



micro-organisms are of the very highest interest just now (vide 

 Pasteur's researches, Ac.) 1 have Cohn's papers. 



Also, will some practical micro.scopist kindly inform me whether 

 the P objective of Zeiss ( = 1-14 in. nearly), is sulBciently powerful 

 with a low eye-piece for the investigation (of Bacilli, io.) ? The 

 stage appliances I possess are of the simplest, and will not permit 

 me to use a higher power. 



I, and I feel sure, many others, would rejoice very heartily if the 

 Editor of Knowledge would arrange for the appearance of micro- 

 scopical papers similar to those on the practical use of the tele- 

 scope now appearing. There does not happen to be any journal 

 which gives poor beginners in microscope technology the aid which 

 Mr. Proctor affords to beginners in telescope work. Will he listen 

 to the cry of A Medic.il Well-wisheb ? 



[Our correspondent will find microscopy was introduced last 

 week. — Ed.] 



TELESCOPE. 



[311] — I should certainly advise "Country Solicitor" (237, 

 p. 275) to invest his money in a silvered glass reflector. He can get 

 one by the first maker in England, of 8i inches aperture and 6i feet 

 focus (the largest size he could conveniently move about), well and 

 firmly mounted, with a battery of nine or ten eyepieces, for £40. A 

 refractor of equal power, i.e. about 7J-inch aperture, would be some 

 10 feet long, would be almost necessarily a fixture, necessitating the 

 erection of an observatory to put it in, and the object-glass alone, 

 without tube, stand, or any accessories, would cost him at least 

 twice as much as the reflector. The latter would certainly be the 

 handier instrument of the two. He would be able to take it out of 

 the house, and set it up in five minutes ; and the silver film would 

 certainly last, if decent care were taken of the mirror, at least two 

 years, and, if tarnished then, would be renewed by the maker for 

 iialf-aguiuea. Either the reflector or refractor would exhibit to him 

 most of the objects in the new edition of Mr. Webb's book ; though, 

 of course, he could not expect to see the inner saiellites of Uranus, 

 or separate the close pairs in such stars as o Equulei or J Sagittae 

 with such an instrument. H. Sadleb. 



VEGETARIANISM. 



[312"' — From letter 207, p. 251, it would appear that there are 

 fanatics to be found amongst the opponents of vegetarianism. 



The case quoted of the prisoners at Waltenburg proves simply 

 nothing. The " theoretically nutritious" food was adopted only on 

 the failure of the potato crop, and was certainly a poor bill of fare, 

 even for a vegetarian. The more generous course which followed, 

 and which created such a marked improvement in the condition of 

 the prisoners, consisted of five articles of diet. Of these, three, at 

 the least, enter largely into the menu of those who advocate the 

 vegetarian system, and would probably have effected the same 

 beneficial results without the aid of either meat or coffee. 



One Open to Conviction. 



CHINESE COUNTING. 

 [313"' — The Chinese have a method of reckoning by the aid of 

 the fingers, including addition, subtraction, multiplication, and 

 division, from 1 up to 100,000. Every finger on the left hand 

 represents nine figures — viz., the little finger units, the ring finger 

 tens, the middle finger hundreds, the forefinger thousands, the 

 thumb tens of thousands. When the three joints of each finger 

 are touched from the palm towards the tip, they count 1, 2, and 3 

 of each of the denominations aforesaid ; 4, 5, and 6 are counted on 

 the back of the finger-joints. In the same way, 7, 8, and 9 are 

 counted on the right side of the joints from the palm to the tip. 

 The forefinger of the right hand is used as a pointer. — Yours, 4c., 



PSCCATI. 



(©ufrirs. 



[269] — RcsT.^Why does salt water rust iron more than fresh 

 wate. — G. W. J. 



[270] — Blowi-ipe Chemistkv. — Could any reader of Knowledge 

 give me the undermentioned information with reference to the 

 blowpipe described in Vol. I., No. 7, page 137 of Knowlbdoe, viz. : 

 How and where the piece of brass is soldered on ? also where the 

 brass nozzle is to go ; also the air balloon and the trumpet mouth- 

 piece ; and for what purpose the hole is bored through tube between 

 A and B of drawiag r as I have tried to form one and failed. — 

 AM-ttKI^K. 



