346 



KNOWLEDGE 



[Fer 17, leo2. 



line* (Gb FCf, Ac, nearly a doKon) in n McClcan'H star opoctroscopo. 

 Pcrliapa Kmuvi.fdok wonUI Iii'lp some of iig bp((innorB by ffiviiiff 

 occiixionally n few pxampIcB liow ccrtiiiii lines inny bo cosily pro- 

 dorcii nitliuiu tlio niil of a Dunscn bunipr, as wo do not nil live in 

 ((ns-ronRiiinin); clistrirls. 



If A. T. C, pnjfr 230, will prick four pin-holos, he will see four 

 invertoil pin«, enrli pin will appear in a circle of its own, whi<'li 

 ovorlaiiR the one next to it ; and if lie will liol.l the piece of card 

 the other way bcfurc and look at the square hole through one of the 

 pin-holes, he will sec the siiuare lengthened outwnnls, and divided 

 into tlirce sections, the lightest in the middle. Two pins will seem 

 to bo in the parallelogram; half of each pin will appear much 

 darker than the other half. Is the appearance mainly dno to 

 iBtorforenco ? C. B. T. 



©iirnrs;. 



[2 IS] — Would any of yonr renders kindly help me in the followiHg 

 difficulty ? 1 have a good many fossils from the Barton clay, 

 liondon clay, and other similar formations. Some of these, viz., 

 (hells, are beginning to crnnible, others, chiefly vegetable remains, 

 have broken out into crystals, and some have after this disappeared 

 into powder. I have also had impressions of leaves, &c., but these 

 hardly lasted a week. Would some fellow geologist kindly inform 

 mo of some means of preserving these fossils from decay, as other- 

 wise it seems a life's labour almost to form anything like a collection ; 

 and also what are the blackish metallic nodules one finds in the 

 London clay ; and are the forms it sometimes takes casts of vegetable 

 remains, as thoy are very similar in appearance ? And, further, 

 are any fossils to be found in the brick earth, such as lies around 

 West Drayton ? and, if so, what kind and whereabouts in the for- 

 mation is the best place to look for them ? — Lkpidodexdrox. 



[249] — AnsTiiACT Kea.soking.— Can any readers of Kxowledgk 

 give mo («) a scientific definition or absolute test for abstract 

 reasoning ? (I) Is objective and subjective reasoning the same in 

 kind and differing only in degree ? (c) Are the two possessed by one 

 and the same individual at the same time ? (d) Does the possession 

 of the former constitute the individual a being of the lower thinking 

 orders, and docs the possession of the latter constitute him a being 

 of the higher thinking orders? — W. L. Abbott. 



[250]— Spectrl-m of Actixr-m. — Has anything as yet appeared 

 in print with regard to its spectroscopic behaviour ?— Mabel W. 



TiAING. 



. [251]— EXCEINITES.— Will some of your geological readers kindly 

 give their \-iews as to the origin and fonnation of the " Encrinus 

 Liliiformis," a characteristic fossil of the Musehelkalk period. In 

 what other strata is it also found ? — Wilfred. 



[252]--SuGAR Analysis.— (1) Is there a chemical test for dis- 

 tinguishing beet-root from cane sugar ? (2) In a given sample of 

 a mixed sugar, could the relative proportions of each be estimated ? 

 (3) What is the best book relating to the subject ?— P. W. K. 



[253]— N.VTURAL llisTORY, ic— Will you kindly state the best 

 work on natural history, conchol»gy, entomology, and meteorology, 

 suitable for reference, and work in all parts of the world ? — H. B. U. 



[254] — ViXES. — If the grape in its native condition is of a purple 

 hue, can anybody inform mo how the white gi-ape has been pro- 

 duced?— M.E. 



[255] — Is there any known means of restoring to well-coloured 

 old prints of flowers, the original red colour which has become 

 black through age ? Deoxidation seems the thing wanted.— X. K. 



[256] — Paraffin.— Is there any simple method of ascertaining 

 the flash-point of paraffin or petroleum oils ?— G. F. S. Call. 



3^fplir£f to (©iifiifs!. 



[310]— Tin: Atomic Thkoby.— For an account of the atomic 

 theory, see the same by Ad. Wnrtz ; translated by E. Cleminshaw. 

 0. Kegan, Paul, & Co., publishers. Watt's diction.iry will give 

 further information, as will the lecture " on the unit weight and 

 mode of constitution of compounds," delivered by Professor Odling 

 before the Chemicnl Society, Feb. 2, which will s'horly be published 

 in the Society's Journal, and also the Ohemu-al Kei/s. There are 

 tables for the solubility of salts, but do not know of any theory for 

 the insolubility of certain substances in certain fluids.- Technical 

 Chemist. 



[220]— CnEMiCAL Analysis.— The following are some of the best 

 toxt-books :— " Valentine's Qualitative Chemical Analysis," price 

 7b. Gd. ; " Frcsenius' Qnnlitntive Analysis," 12s. 6d. ; also " Quan- 



titative Analymi," 16«. ; " Satton's Handbook of Volnmetr^ 

 AnnlyHig," 15»., nil published by Mesam. Churchill.— Tkcdmcii 

 ClIEMIRT. 



[221]— Schwpgler's "History of Philosophy" is undoubted! 

 the best. James Hutchison Stirling's translotion is published I 

 Edmonston A Co., Kdinburgh, price 6b.— G. A. Keitomix. 



[223]— AxiMXE Dtes.— Kmest L. K. would find a short :,rr,, 

 of the aniline dyes in Watt's Dictioiiar)', under Phenyiainin' I 

 more exhaustive article, see "Chemistry of the Arts anl ' 

 factures," "Aniline and Aniline Dyes," page 20^1.— Tj.< n sn a 

 Chemist. 



[22 1] — Electrical.— The "rubber" for a cylindrical marhit;. 

 may bo made by attaching a piece of leather to u piece of w^od t> 

 required size, and stiiDing it with hor.whair ; then rub or - 

 sodium amalgam. It is not necos-sary to varnish the ( ;. , i 

 though it is an advantage, in so far as it helps to keep moisture f n . 

 condensing on it. — Amateur. 



[22t]— Electricity.-" A Greenock Student" will find the din-' 

 tionshe requires in Chambers's "KIcetricity," published at Is^nnd • 

 bo obtnincd from any bookseller), whicli would l» much bet!, r •! 

 a reply through the Query column of your paper, aa it give- :: , 

 ings. It is not necessarj- that the cylinder be covered with .i.i.;... 

 varnish. Indeed, I never heard of that being done bi-fore. — J.M. ( 

 [233] — Biological — Physically, the difference between ape an 

 man is much greater than that between man and man. Bu 

 mentally, not. The range of variation in the capacity of the brain- 

 case of man (healthy adult) is between 50 and 110 cubic in. ; th- 

 difference between the gorilla brain-case and the lowest hnma' 

 is only 13 cubic in., i.e., between 37 and 50 cubic in. (2.) T! 

 thyroid gland in the higher vertebrates has, by the research' < <■: 

 Mr. Balfour, been recognised as the rudiment of an organ r ,'!c : 

 the cndostyle, whicli occurs in the lowest group of the vert' ! :a! 

 the Tunicata. (See p. 597, " Huxley's Invcrtebrata.") Tlii< ■ ■ _•: 

 takes the form of a longitudinal groove lying on the floor''; t 

 pharynx. Its function appears to be to secrete a kind of niucw- 

 whieh assists the process of swallowing food, though this latti : 

 point is open to qne«tion. In the floor of the month of vertebral' 

 embryos, there appears a similar groove, which ultimately developc- 

 iuto the thyroid gland. (3.) Darwin in the " Descent of Man. 

 quotes several in.'itances of human beings with projecting caud:/ 

 vertebra?, and I may say fiu-ther that I know an indivi^oa! 

 now living who has such a tail. There have Ijeen many account - 

 published of races of men so adorned existing in regions sufficiently 

 remote to prevent speedy refutation; but, so far as I know, ther 

 all lack corroboration. Herodotus mentions a tribe of Centr.il 

 Africans with tails, but not having access to his work just now, 1 

 cannot give details. I am indisposed to accept any of these state- 

 ments, as it would be directly contrary to the theory of evolution 

 to suppose that a useless structure should reappear and ix'rsif' 

 in a race after it had once been lost, and man's nearest allie» 

 among the apes have no tails. (1.) The Neanderthal skall 

 (n.) 'The brain capacity cannot bo definitely ascertained, a- 

 only the roof of the cranium is preserved ; but it is very small, 

 probably below 40 cubic inches, (b.) The fragment of skull 

 is remarkable for immense bony ridges projecting over th« 

 eye-orbits, of apparently nearly half an inch, and snggostini; 

 at once a comjiarison with those of our " poor relations," th'' 

 gorillas. The facial angle cannot be ascertained. The back par: 

 of the human head where the muscles of tho neck are attached, 

 is marked by a slight ridge, called the '' Lambdoidal crest." Xow. 

 the back of the head will be found to i)roject considerably behimi 

 this point in the skull of an European, while in the lowest modem 

 type (the Australian) it ascends perpendicularly to some height, 

 but in the Neanderthal skull it slopes directly upwards and fonvards. 

 thus greatly diminishing its capacity. In addition to this, the brain- 

 case is very shallow, as the following measurements will show : — A 

 line drawn from the " Lambdoidal crest" to the front of the brow 

 ridge gives a length of 7J in., against an extreme length of 7| in. in 

 an average European skull. The height of the Neanderthal skull 

 above the line indicat"d is 3 J in., while that of tho European is -t-J in. 

 Extreme width of Neanderthal skull 53 in., European 5Jin. Thi' 

 length of the Neanderthal skull is apt to mislead, as the great brow 

 ridges are not excavated to receive the brain. Professor HuiIpt 

 remarks that this is the lowest type of human skull that has been 

 discovered. The skull was found in what is called a Cave Breeoit". 

 and belongs to the so-called " Palaeolithic ]>criod," which, however, 

 is so ill-defined as to giro a verj- indifferent idea of its exact ajfc. 

 though we must certainly regard it as being tens of thousands ef 

 years old. — Old Fos,<il. 



[230]— Bcsser, " PrimitiaD Floitc Galicia-," Paris, ISOO; Brotem. 

 "Flora Lusitanica," Madrid, 1804; Picot de la Peyrouse, " Floivi 

 des Pyr^n^es," Lyons, 1793-1802. All in the B. M. Library.— 

 U. C. "F., B.Sc. 



[250] " C. E. H.," and [198] " J.H. B."— Trk iiix.E.— The eating. 



