1(H2 



KNOWLEDGE 



[Dkc. 



1881. 



Uu tlio Gront Bcor boon mndo u»o of by "ony people for 

 inoasurinK time, in connection witli the Dog-star or nny other? 

 Bentley, in lila Hindu AHtronomy, siiyH tUat the Uindux had the 

 following method of nieiiHuring the amount of preeeMtnii ; They 

 U88unied an imaginnrv line, or great circle, passing through the 

 poles of tho ecliptic and the l)e)^inning of one of their lunar 

 astcrisms called Mo'ilin (instead of tweke solar signs, they had 

 twenty-soven lunar asterisms). This great circle, which was 

 called tho line of tho liishis, was supposed to cut some of tlie stars 

 of tho Great Hear, and the precession was noted by stating the 

 degree, Ac, of any iiu^iviMc lunar nstcrism cut by that Hied line 

 or circle as an index. That is to say, their asterisms shifted, pre- 

 cessionally, juit as our " Aries " has got into I'iseea, and they 

 measured the amount of precession by the passage of the asterisms 

 over the assumed fixed line. This fact suggests to me to ask 

 whether the Egyptians made out nny similar connection between 

 the Great Bear and Sirius, or between the Pole-star and Sirius. I 

 know that a lino drawn through " the pointers " would not pass 

 through Sirius, because the Kight Ascension is so different ; but is 

 any sort of connection knonn to have existed? — tiF.oiiCK St. Ci.air. 



[58] — SiBius AND Orio.n. — I have met with a statement that Sirius 

 is in the shoulder of Orion. Knowing that Sirius was in the Great 

 Dog constellation. 1 was puzzled. Did the Orion constellation at 

 any time include Sirius ? — Geo. St. Clair. 



[59] — Mkrci'ry's Revolutiox. — The "Science Primer on As- 

 tronomy" (by J. Norman Lockyer, F.R.S.), p. C2, says that 

 Mercury is 8-1 days in traversing its orbit. Jlost books which I 

 liave looked into give Mercury's sidereal revolution as S7 days 

 23 hours 15 minutes 43 seconds. Is the sidereal revolution some- 

 thing different from the " traversing of the orbit ? " — George 

 St. Claib. 



[GO] — Sound. — How does sound penetrate through a brick wall ? 

 — S. 



[61] — Will the Editor, or anyone else, inform me the name of the 

 great comet that appeared in our northern sky this last midsummer; 

 also, how long it takes to make one journey round the sun ? — 

 S. C. H. 



[62] — Alool. — Wliere abouts in Pcrsius is the variable star 

 Algol ? If this is tho same star as in the head of Medusa, I suppose 

 the latter constellation is a i)art of the former. Is it so ? — F. H. S. 



[63] — Algol and Mika.— When are Algol and Mira at their 

 brightest ?— F. H. S. 



[64] — Star Letters and Nvmbers. — Not having examined a 

 stellar map before those that appear in Knowledge, will you kindly 

 explain the following ? I have been under the impression that tho 

 stars of all constellations are named after the Greek letters, aud 

 when these arc exhausted, the numerals are then resorted to, begin- 

 ning, of course, at 1 ? I find this is not the case, e.g., take Lynx, 

 as marked in tlie map on No. 1. The brightest star is of the fourth 

 magnitude, and is n ; there are only two others marked in thi.s 

 •constellation, but instead of their being /3, y, or 1, 2, thev are called 

 31 and 38.— K. H. S. 



[65] — New Star in Cassiopeia. — I am told that a periodical star 

 in Cassiopeia will shortly appear, and it will be so bright as to be 

 seen at noonday. Is that so ? — V. H. S. 



[66] — Has Venus ever been seen in the daytime ? — F. H. S. 



ixrplifg to ©iifrifsf. 



[11]— LoGARiTnus. — Without knowing the extent of accuracy 

 desired by Mr. (Jrundy (query 11, p. GO) in his computations, it is 

 difficult to advise him as to the class of tables he retiuires. Copies 

 of the ordinary " Seven-place " tables of Uutton, Habbage, Sang. 

 and others are easily procured second-hand (tho first for pre- 

 ference) ; (Jcrman tables to |six places, by Ursinus and Bremiker, 

 can be purchased at Nutt's; and tho best of several five-place logs, 

 will be found in Oalbraith it Haughton's series, now published by 

 Cassell. This includes u table of " Sum and difference" logs, by 

 Gauss. Tho last table is made si)ccially applicable to Life con- 

 tingencies and the general formation of tables by a continuous 

 method, by P. Gray, who inserts it in his " tables and forniuhe," 

 tabulating for each log. that of tho function 1-h.r. An error in 

 Babbage may hero bo noted. In the eight-figure series attached to 

 his larger table, the log. of 103 (an important figure, as being the 

 initial 1, plus its interest at 3 percent.) should be 01283722, not 

 01283723. Tho most complete table of Anti-logarithms is the old 

 folio of Dodson, frequently to be picked up at the stalls; see also 

 S'lortrede's tables to seven placesin the usual form. — Yours faithfully, 



H. S. A.' 



[19]— Comparative An.vtomy of Bibor and A.mhaiji. — Charloi* 

 SherlMjrn asks, What are the corresponding bones in man and other 

 mammalH to the " furcida " (furculum) of binls ? I am surprised 

 Mr. Slierborn hag not iliscovered the answer to his ipierj- iu any 

 good manual of zoology. The " furculum " of a bird (anyli'^, the 

 ** merry-thought ") is composed of the two c'>llar-bones or claviclcH 

 *if the bird, which are, in nu)8t cases, firndy united to form one 

 l)One. This bone, in turn, is joined to the breast-bone, and forms 

 a strong arch, or, rather, keystone, of the shoulder. It should 

 be remembered that in a bird's shoulder there are three typical 

 bones — scapula, or shoulder-blade ; clavicle, or collar-bone ; and 

 coracoid bone — on each side. The coracoid bone, developed as a 

 distinct bone in birds, reptiles, and lower vertebrata, is represented 

 in all mammals, except the lowest, as a mere process (coracoid 

 process) of tho shoulder-blade. In the lowest mammals ('.'J., 

 Ornithnrhijiichuii and Krhidtta of Australia) tho coracoid. as in the 

 bird, is articulated with the brea.st-bone. In this resi>ect,ii.s well as 

 in the absence of sutures or distinct lines of union between the 

 skull-bones, and in other joints of internal anatomy, the lowest 

 quadrupeds present a striking affinity to birds. — Andrew Wilson. 



[25] — FoRM.s OF Food. — As explanatory of the terms relating to 

 food in Dr. Carpenter's paper, which puzzle " Desdichado," I would 

 advise him to read a simple elementary treatise wherein foods at 

 large are treated. Such a book as Corfield's " Laws of Health," 

 Is. Gd. (Longmans), will assist him. Foods are divided into (1) 

 Nitrogenous (containing carbon, hydrogen, oxygen, and nitrf>gpn, 

 and sometimes sulphur and phcsphorus) and (2) non-nitrogenous. 

 Of the latter, there are four chief varieties: — (1) Water (11 j' I) ; 

 (2) fats and oils (CHO) ; (3) sugars and starches (amyloids or 

 hydro-carbons) (CHD, but differing from fats in the amount of O 

 they contain) ; (4) minerals (e.g. lime, salt, iron, 4c.) " Desdi- 

 chado " will obtain all necessar}' information concerning foods from 

 any primer of physiology, and such knowledge should form, indeed, 

 part of every .system of school training. — Andrew Wilson. 



TRAINING. 



WE have before now spoken of the singular views which have 

 prevailed with regard to the diet best suited for men who 

 were desii'ous of developing their physical powers to the highest 

 degree, and of the harm which has been done by the empirical, and 

 in many cases ridiculous, rules which were laid down. Some of the 

 most objectionable of these are now happily set aside, and the 

 opinions of those intelligent persons who taught that mutton was 

 better than beef for " wind," that all fluids should be avoided by 

 men who wish to "get into condition," that meat was to be eaten 

 without salt, and that pedestrians should drink sherry and boxers 

 port, would be laughed at, even by tho most ardent fanatic in an 

 Eiglit ; but, though a good deal of nonsense has been got rid of, a 

 bad system still prevails, and there is no exaggeration in stating 

 that harm is still done by the regulations respecting diet which, 

 even in these days, are unhesitatingly obeyed. At one time, no 

 doubt, some of these rules appeared to liave a certain scientific 

 sanction ; but it has now been well established that tho views on 

 which this sanction was based were not only erroneous, but directly 

 opposed to the truth. In so far, therefore, as rules which are in 

 accordance with them have any effect, they must have a bad effect. 

 It is true that they do not work so much ill as might be ex|>ected, 

 but this is because the men who follow them are usually very 

 young, very vigorous, and lead, ajiart from diet, a most healthy life. 

 Still, unless moilern physiological teaching is altogether wrong, 

 even the modified system now followed nmst cause some evil, and 

 the sooner it is swept away tlie better. If it be siiid that the men 

 who train steadily often attain very " high condition," the answer is 

 tliat this is due in no way to their food, but to constant and fitting 

 exercise in the open air, to regular hours, to strict temperance with 

 regard to alcohol, and to abstinence from, or great moderation in, 

 smoking. Strength is attained not by diet, but in spite of diet. 



That erroneous views should at one time have been held is not 

 wonderful, for in support of them the great name of Liebig could 

 be quoted by those who had sufficient energy and intelligence to 

 attcmjit a scientific study of the question. It is now, however, 

 well establislicd that in some of his conclusions Liebig was wrong, 

 and notably that he was wrong in thinking that muscular or 

 mechanical effort was entirely supported by nitrogenous food, and 

 that the heat-giving foods sustained the process of combustion 

 which is constantly going on in the body, but did nothing morc. 

 If he was right, of course, the more muscular work a man did, the 

 more nitrogenous food he would require ; and trainers were there- 

 fore not mistaken in favouring meat, and in looking with great dis- 

 like on those foods which are commonly thought to produce fat ; 

 but then, unfortunately, Liebig has been shown to have been in 

 error, and any system of diet which is in accordance with his views 

 cannot be a good one, and is in all probability a very bad one. The 



