^4 



NA TURB 



[November 23, 1899 



An example of this kind has already occurred in Saint- 

 Venant's edition of Navier's " Le9ons de Mecanique." This is 

 compared with the present results. The paper also investigates 

 the critical sections when the two cases of four and two fail- 

 points pass into one another. It is shown in particular that 

 when the angle between the asymptotes is less than 73° the 

 greatest stress always occurs at the neck of the section. 



The second type of section is bounded by one ellipse and one 

 branch of a confocal hyperbola. 



The case in which the confocal hyperbola reduces to a straight 

 slit or thin keyway is specially studied. 



For the first type of section this case gives two thin key- 

 ways ; for the second only one. 



The manner in which the reduction of the torsional rigidity, 

 due to cutting such slits into the material, varies with the depth, 

 is very striking. This reduction, which is as great as »23 per 

 cent, when the depth of the keyway is 0*6 (semi-major axis) 

 falls to about i per cent, when this depth is o*i2 (semi-major 

 axis). This would account for such keyways not always giving 

 in practice the reduction in torsional rigidity which we should 

 expect from Saint-Venant's results for the circle. Keyways of 

 only moderate depth will affect the torsional rigidity very little. 



Finally, the effect on the torsional rigidity of two such equal 

 and opposite slits is shown to be about twice the effect of a 

 single slit. 



Chemical Society, November 2. — Dr. W. H. Perkin, 

 Vice-President, in the chair. — The following papers were read : 

 On methods for determining the relative proportions of gaseous 

 chloroform and air in a mixture of the two, and on a method for 

 producing a mixture of air and chloroform in any desired pro- 

 portion, by A. Vernon Harcourt. — The theory of saponification, 

 by J. Lewkowitsch. It is demonstrated that partially hydrolysed 

 fats contain di- and mono-glycerides, and that the hydrolysis of 

 triglycerides constitutes a bimolecular reaction. — Note on the 

 action of dilute nitric acid upon oleic and elaidie acids, by 

 F. G. Edmed. Dilute nitric acid converts oleic acid quantita- 

 tively into elaidie acid.^ — Formation of tetrazoline, by S. Ruhe- 

 mann and H. E, Stapleton. A good yield of tetrazoline, 



CH<\^-vr nyr'TT^CH, Is obtalncd by heating monoformylhydr- 



azide. — Asymmetric optically active nitrogen compounds. 

 Dextro- and lEevo-benzylphenylallylmethylammonium iodides 

 and bromides, by W. J. Pope and S. J. Peachey. On heating 

 «-benzylphenylallylmethylammonium iodide with silver dextro- 

 camphorsulphonate and acetone, a mixture of the camphor- 

 sulphonates of the dextro- and Isevo-quaternary ammonium 

 derivates is obtained. From these salts the corresponding and 

 optically active iodides and bromides may be prepared. It is 

 thus proved that dissolved substances may owe their optical 

 activity to asymmetric nitrogen. — Camphoroxime. Part III. 

 Behaviour of camphoroxime towards potassium hypobromite, 

 by M. O. Forster. Camphoroxime yields, when treated with 

 potassium hypobromite, a nitroso-derivative, CjoHieBrNgO, 

 which is converted into a compound of the composition 

 CioHi4BrNO by sulphuric acid ; on treating either substance 

 with soda, a nitrite, C9H13N, and an amide, CgHjgNO, are pro- 

 duced. The latter seems to be campholytic amide. — Optical 

 influence of an unsaturated linkage on certain derivatives of 

 bornylamine, by M. O. Forster. — The interaction of sodium 

 hydroxide and benzaldehyde, by C. A. Kohn and W. Trantom. 

 Electrolytic preparation of induline dyes, by E. C. Szarvasy. 

 On electrolysing a fused mixture of aniline and its hydrochloride, 

 the following substances are formed : induline, anilidoinduline, 

 induline 6 B, and azophenine. — The heat of combination of 

 copper with zinc, by T. J. Baker. — The action of sulphuric 

 acid on fenchone, by J. E. Marsh. 1:2: 4-Acetorthoxylene is 

 produced by the action of sulphuric acid upon fenchone. — On 

 glucosides, by H. Ryan. — Note on polyazo-compounds, by R. 

 Meldola and W. A. Williams. — On ethyl dibromobutane- 

 tetracarboxylate and the synthesis of tetrahydrofurfuran-ao'-di- 

 carboxylic acid, by B. Lean. — The application of powerful 

 optically active acids to the resolution of externally compen- 

 sated basic substances. Resolution of tetrahydroquinaldine, by 

 W. J. Pope and S. J. Peachey. — The application of powerful 

 optically active acids to the resolution of feebly basic substances. 

 Resolution of camphoroxime, by W. J. Pope. — The application 

 of powerful optically active acids to the resolution of externally 

 compensated basic substances. Resolution of tetrahydropara- 

 toluquinaldine, by W^. J. Pope and E. M. Rich. — Homogeneity 

 of dextrolaevo-o-phenethylamine dextrocamphorsulphonate, by 



NO. 1569. VOL. 61] 



W. J. Pope and A. W. Harvey.— The characterisation of 

 racemic liquids, by F. S. Kipping and W. J. Pope.— A method 

 for discriminating between " non-racemic " and "racemic" 

 liquids, by W. J. Pope and S. J, Peachey.— On two hydrated 



cobalt oxides, green- and buff-coloured, by W. N. Hartley. A 



method of separating isomeric xylidines from the commercial 

 product, by W. R. Hodgkinson and L. Limpach.— Action of 

 hydrolytic agents on a-dibromocamphor and the constitution of 

 bromocamphorenic acid, by A. Lapworth. 



Entomological Society, November i. — Mr. G. H. Verrall, 

 President, in the chair. — Mr. J. J. Walker exhibited two living 

 specimens of Bostrychus cornutus. Fab. , obtained from a wooden 

 stool which was brought from Zanzibar. — On behalf of Mr. W. 

 Purley, of Folkestone, Mr. C. G. Barrett exhibited the follow- 

 ing species of Lepidoptera : — Stigtjionota trauniana, Lozopera 

 beatricella, Peronea cristana, Cledeobia angtistalis, Crumbus 

 inqtiinatellus, var., Eudorea dubitalis, var. ingratella, and 

 Endotricha flammealis.—yix. McLachlan showed four examples 

 of Deilephila lineala, taken by Mr. E. W. Hainworth at Victor, 

 Colorado, at an elevation of 9000 feet, on July 23, 1899 ; also 

 an ash-twig which had been girdled by hornets, the observation 

 of this curious fact having been made by Mr. W. C. Boyd, of 

 Cheshunt, from whom he received the twig. — Dr. T. A. Chapman 

 exhibited specimens of Erebia Jiavofasciata taken at Campo- 

 lungo at an elevation of 7000 feet. He stated that the species 

 occurred only in those places where there was an outcrop of 

 dolomitic strata belonging to the crystalline schists, and was 

 not met with elsewhere at that elevation, nor was it to be found 

 in association with the same strata at lower levels. — Mr. H. J. 

 Elwes exhibited and gave a brief account of a collection of 

 Lepidoptera made by Mrs. Nicholl and himself in a part of 

 Bulgaria which had not previously been visited by entomolo- 

 gists. Lycaena erotdes, L. anteros, L. zephyrus, Mclittaea 

 cynthia, Erebia gorge, and Coenonympha typhon were a few of 

 several interesting forms to which he directed attention. 



Linnean Society, November 2. — Dr. A. Giinther, F.R.S., 

 President, in the chair. — Prof. Stewart, F.R.S., exhibited and 

 made remarks on a preparation of the leaves of Mimosa piidica 

 showing the diurnal and nocturnal positions. He also exhibited 

 the embryo and egg-cases of Cestracion Philippi. — Rev. G. 

 Henslow (read a »paper on the proliferous state of the awn of 

 Nepal barley. After describing the two varieties Hordeum 

 coeleste, vars. Aegiceras and trtfurcatum, he showed that the 

 inverted flower-buds (which constitute the peculiarity of the 

 monstrosity) were different in the two varieties. — Dr. W. G. 

 Ridewood read a paper on the hyobranchial skeleton of the 

 new aglossal toad, Hy7nenochirus Boettgeri. The hyoidean 

 cornua of this animal was shown to be ossified, a fact unique 

 among tailless amphibians. — Mr. Harold Wager read a paper 

 on the eye-spot and flagellum in Euglena viridis. 



Mathematical Society, November 9. — Lord Kelvin, 

 G.C.V.O., President, in the chair.— The President stated 

 that the Council, as announced at the June meeting, had 

 awarded the De Morgan medal to Prof. W. Burnside, F. R.S. 

 After Major MacMahon, R.A., F.R.S., on behalf of the 

 Council, had stated the grounds of the award, the President 

 presented the medal to Prof. Burnside, who suitably thanked 

 the Council for the honour they had conferred upon him. — The 

 following gentlemen were elected the Council for the ensuing 

 session : President, Lord Kelvin ; Vice-Presidents, Prof. Elliott, 

 F.R.S., Lieut. -Colonel Cunningham, R.E., Prof. Lamb, 

 F.R.S, ; Treasurer, Dr. J. Larmor, F.R.S. ; Secretaries, R. 

 Tucker and Prof. Love, F.R.S. ; other members, Prof. Burn- 

 side, Dr. Glaisher, F.R.S., Prot. Hill, F.R.S., Dr. Hobson, 

 F.R.S., A. B. Kempe, F.R.S., Dr. F. S. Macaulay, H. M. 

 Macdonald, Major MacMahon and E. T. Whittaker. — Prof. 

 Burnside communicated a short note by Dr. L. E. Dickson on 

 the abstract groups isomorphic with the symmetric group on k 

 letters. — Major MacMahon spoke on the fundamental solutions 

 of the indeterminate relation \x i /y. — The following papers 

 were read in abstract. Certain correspondences between spaces 

 of n dimensions, by Dr. E. O. Lovett. ( i ) On the form of lines 

 of force near a point of equilibrium ; (2) the reduction of 

 conies and quadrics to their principal axes by the Weier- 

 strassian method of reducing quadratic forms ; and (3) on the 

 reduction of a linear substitution to a canonical form ; with some 

 applications to linear differential equations and quadratic 

 forms, by T. J. I. Bromwich : (i) on Ampere's equation 

 Rr -I- 2Sj- + T^ + U(r/ - S^) = V, and (2) the theory of auto- 



