April 12, 1900] 



NA TURE 



579 



valuable collection of native objects from Baram was exhibited 

 during the evening. — At the forthcoming meeting, Tuesday, 

 April 24, Prof. Haddon will give a similar account of the re- 

 searches of the Cambridge Expedition in Torres .Strait, and 

 Dr. Rivers will describe his genealogical method of collecting 

 social and vital statistics, which was applied with success in the 

 same district. 



Zoological Society, April 3. — Prof. G. B. Howes, 

 F.R.S., Vice-President, in the chair. — Mr. G. E. H. Barrett- 

 Hamilton contributed a paper, entitled " Notes on Mus 

 sylz'atiais and its Allies, Subspecies and Geographical 

 Variations." — A communication was read from Mr. Stanley S. 

 Flower containing an account of the Mammals of Siam and 

 the Malay Peninsula. — Mr. A. Smith Woodward communicated 

 a paper, by Dr. Einar Lonnberg, on a piece of skin found 

 along with the remains of Grypotheriurn in Cueva Eberhardt, 

 Patagonia. A detailed description and comparison of the 

 specimen led to the belief that it belonged to the extinct horse — 

 Ottohippidium. Dr. W. G. Ridewood added a note on the 

 structure of the hair bordering two equine hoofs, probably 

 fretal, found in the same cave by the La Plata Museum 

 expedition. The hair agreed in most respects with that described 

 by Dr. Lonnberg, and thus seemed to confirm his deter- 

 mination. — Mr. C. Warburton exhibited and described a 

 remarkable new Attid Spider {Maiitisatta iriicidatis), the chief 

 characteristic of which was the possession of predaceous front 

 legs, the spines being so arranged as to form a prehensile 

 weapon. It had been taken in Borneo. 



Mineralogical Society, April 3. — Prof. G. D. Liveing, 

 F.R.S., Vice-President, in the chair. — Prof. W. J. Lewis 

 showed the application of Grassmann's method to the calcula- 

 tion of the angle between two poles. — Mr. R. W. H. T. 

 Hudson gave a solution of the problem to determine the position 

 of points and planes after a rotation through a definite angle 

 about a known axis. — Mr. L. Fletcher described the methods 

 employed in the chemical analysis of the Mount Zomba 

 meteorite. — Dr. A. Hutchinson gave the results of a deter- 

 mination of the refractive indices of chalybite and diallogite. — 

 Mr. G. T. Prior pointed out the close crystallographic relation- 

 ship between hamlinite, florencite, beudantite and svanber- 

 gite, and showed that in chemical composition these minerals, 

 together with plumbogummite (hitchcockite), all conform to 

 formula analogous to that of hamlinite if, in the case of beu- 

 dantite and svanbergite, one molecule of P2O5 be regarded as 

 replaced by two molecules of SO3, i.e. by SjOg ; in conformity 

 with this result the alkaline earth in svanbergite was found to 

 be strontia and not lime. — Mr. Prior also contributed a paper 

 on /Egyrine- (and Riebeckite) -Anorthoclase rocks from near 

 Adowa, Abyssinia, which form a series strictly analogous to 

 Briigger's " Grorudite-Tinguaite " series of the Christiania 

 district, the more acid group containing quartz, and the more 

 basic, nepheline. — Prof. H. A. Miers exhibited specimens of 

 anatase and brookite from Tremadoc. 



Mathematical Society, April 5. — Lieut. -Colonel Cunning- 

 ham, R.E., V. P., in the chair. — The following communications 

 were made : — On the addition theorem for the Bessel functions, 

 by Mr. H. M. Macdonald. — The orthopticloci of curves of a given 

 class, by Mr. A. B. Basset, F. R.S. — The uniform convergence 

 of Fourier's Series, by Prof. Love, F.R.S.— Extension of 

 orthogonal and Boolian co-variants, by Major MacMahon, 

 F.R.S. — A paper was also received from Mr. Bromwich, entitled 

 "On Weierstrass's canonical reduction of a ' schaar ' of bi- 

 linear forms." — The chairman announced that the May meeting 

 would be made "special," in accordance with a resolution 

 already made known to members. 



Manchester. 



Literary and Philosophical Society, April 3.— Prof. 



Horace Lamb, F.R.8., President, in the chair. — A paper on 



*' Aerial Locomotion" was read by Mr. Henry Wilde, F.R.S. 



Edinburgh. 

 Royal Society, March 19.— Lord Kelvin, President, in the 

 chair. — Dr. Thomas Muir communicated three papers: (i) A 

 development of a Pfaffian having a vacant minor ; (2) the 

 theory of alternants in the historical order of its develop- 

 ment up to 1841 ; (3) Jacobi's expansion for the difference- 

 product, when the number of elements is even. In the first 

 paper, the expansion was obtained as a sum of partial products, 

 each of which was a minor determinant multiplied by the com- 



NO. 1589, VOL. 61] 



plementary minor Pfaffian of the original Pfafifian ; and the third 

 paper contained a proof of Jacobi's rule for expanding the 

 difference-product {a, h, c . . .) 2i?.z. series of partial products, 

 each of which is a Permanent multiplied by a Pfaffian. — Dr. A. 

 Gait read a paper on the heat of combination of metals in the 

 formation of alloys, completing the work of previous papers on 

 the same subject. It was shown that, in the formation of 

 copper and zinc alloys, the heat of combination was negative for 

 small percentages of copper ; then, as the amount of copper was 

 increased, it became positive, and obtained a maximum when 

 the percentage of copper was about 38. For higher and increas- 

 ing percentages of copper the value of the heat of combination 

 gradually fell off to zero. 



Paris. 

 Academy of Sciences, April 2. — M. Maurice Levy in the 

 chair. — On a new gaseous body, sulphur perfluoride, by 

 MM. H. Moissan and P. Lebeau. By the action of fluorine 

 upon sulphur two fluorides of sulphur are produced, only one 

 of which is absorbed by potash. The unalisorbed gas, which 

 is very stable towards chemical reagents, has the composition 

 SF„.— On the origin of the fossil trunks in the coal-measures, 

 by M. Grand' Eury. From a study of the positions in the coal- 

 measures in which Cal. catinoefornn's, Arthropitus and Caiamo- 

 dendron occur, the author concludes that there can be no doubt 

 that these Calamites are not in the position in which they origin- 

 ally grew, as is proved by the numerous adventitious roots sur- 

 rounding the stems. — Report on a memoir of M. Torres, 

 entitled " Calculating Machines." The paper gives a com- 

 plete theoretical solution of the problem of constructing 

 algebraical or transcendental functions by machines. There is- 

 also an .iccount of a machine actually constructed for the 

 solution of certain types of algebraical equations of which 

 frequent use is made. — Prof. Van der Waals was elected aCorre- 

 spondant in the Section of Physics in the place of Sir G. G. 

 Stokes, elected Foreign Associate. — Remarks on the criterium 

 of Tisserand, by M. Gouey. A discussion of a theorem given, 

 by Tisserand to decide if two different orbits given by observa- 

 tion may or may not belong to the same comet, owing to the 

 effect of attraction of a planet. — On differential equations of the 

 third order with fixed critical points, by M. Paul Painleve. — On 

 an inversion of a double integral, by M. J. Le Roux. — On the 

 geometrical applications of Abel's theorem, by M. Ch, Michel. 

 — On a machine for solving equations, by M. Georges Meslin. 

 The machine consists of a balance carrying upon its beams at 

 varying distances from the point of support a series of solids of 

 revolution, partially immersed in a liquid. If the depth im- 

 mersed is X, the forces exercised upon the solids are represented* 

 by .r", jr"', JT"" ; they act at distances/, p' , p", and there is the 

 force A acting at unit distance. Hence x satisfies the equatioiv 



/JT" -I- Z'x"' + . . . +p"x-" = A, 

 and the height x will be the solution of the equation. The 

 solution of the equation $x^ - ^x- - Jx — A is worked 

 out as an example. — On the property of certain bodies of 

 losing their phosphorescence by heat, and of recovering it on 

 cooling, by M. Gustave le Bon. Some radio-active barium- 

 chloride was found to lose its power of phosphorescing at 

 200°, but to regain it on cooling. Quinine sulphate was 

 found to behave in a similar manner. — Velocity of propa- 

 gation of electro-magnetic waves in bitumen, and irv 

 bitumen covered wires, by M. C. Gutton. It was found« 

 experimentally that in bitumen the electro-magnetic waves 

 are propagated with the same velocity, whether they are 

 guided by wires or not. — On the production of electrostatic 

 images in sensitised plates, by M. W. Schaffers. The resuhs 

 obtained are of interest from the point of view of the exploration 

 of an electric field.— On the influence of iron on the discharge 

 of a condenser through an induction coil, by M. G. A. Hemsa- 

 lech. The introduction of the iron diminishes, and finally de- 

 stroys, the oscillatory character of the current, the changes being 

 readily studied by the appearance of a Geissler tube placed in 

 the circuit. The effect of the iron is analogous to that produced 

 by the introduction of a large resistance.— On some optical pecu- 

 liarities of Geissler tubes under the influence of a magnetic field, 

 by MM. N. Egoroff and W. Georgiewsky.— The use of new 

 radio-conductors for telegraphy without wires, by M. C. Tissot. 

 The Branly tube is placed in a magnetic field, the lines of force 

 of which are parallel to the axis of the tube, the powder being 

 composed of some magnetic substance — steel, nickel or cobalt. 

 The sensibility of the apparatus is thus greatly increased. 



