November 24, 1910] 



NATURE 



129 



quantity, and at a temperature of 1500° absolute was 

 290 cm. per second. From a theoretical formula it was 

 further deduced that the ion at this temperature had the 

 mass of a hydrogen atom. Experiments are proceeding to 

 test further this latter result. — G. W. Todd : Mobility of 

 the positive ions in gases at low pressures. By an adapta- 

 tion of Rutherford's alternating field method, the mobili- 

 ties of the positive ions produced in gases by means of 

 X-rays have been measured between pressures of i and 25 

 millimetres of mercury*. Unlike the negative ions, no 

 change was observed in the law that the product of the 

 pressure and the mobility is constant for the same gas. 

 Further experiments are in progress with the positive ions 

 given off from aluminium phosphate. — G. H. Hardy : 

 Fourier's double integral and the theory of divergent 

 integrals. 



P.ARIS. 



Academy of Sciences, November 14. — M. Emile Picard 

 in the chair. — The president announced the death of M. 

 Tannery, free member of the academy.- — M. L. Teisserenc 

 de Bort was elected a member in the place of M. E. 

 Rouch^. — A. Perot : The spectroscopic measurement of 

 the rotation of stars possessing an atmosphere, with 

 special reference to the sun. A mathematical investiga- 

 tion showing that, in the absence of knowledge as to the 

 true direction of the light ray at the point where it meets 

 the reversing layer and of its propagation in the layers 

 through which it then passes, caution is needed in trans- 

 lating radial velocities into velocities of rotation. — M. 

 •lavelle ; Observations of Halley's comet made at the 

 ' Nice Observatory" with the Gautier equatorial of 76 cm. 

 ! aperture. Observations are given for November 3. 8, 10, 

 n, and 12, together with the positions of the comparison 

 stars. The comet was extremely faint, being reduced on 

 November 3 to a vague white spot about i' in extent, 

 ' without visible condensation. — P. Chofardet : Observa- 

 tions of Cerulli's comet (1910c) made at the Observatory 

 of Besangon with the bent equatorial. Data are given 

 for November 10, 11, and 12. The comet appeared as a 

 round nebulosity 30* to 40' in diameter, and was estimated 

 to be of the eleventh magnitude. — M. Cogrgria : Observa- 

 tion of Cerulli's comet made at the Observatory of 

 Marseilles with the Eichens equatorial of 26 cm. aperture. 

 Data given for November 11. — Louis Bachelier : The 

 movement of a point or material system submitted to the 

 , action of chance forces. — M. Arnodin : The bridge at La 

 i Cassagne (Gisclard system). .An account of a suspension 

 ( bridge of a new type constructed on the electric railwav 

 over the Pyrenees between Villefranche and Bourg.-^ 

 Madame M. Dussaud : Discontinuous sources of light. 

 \ commutator is fixed on to the mechanism of a kinemato- 

 graph in such a manner that the lamp is extinguished 

 I during the time that a forward step is made by the film, 

 ! the latter being only illuminated when stationary. The 

 advantages of this arrangement are enumerated. — Jean 

 Becquerel : Polarised phosphorescence and the correla- 

 tion between the polychroism of phosphorescence and the 

 polychroism of absorption. An account of experiments on 

 the phosphorescence of rubies at low temperatures (the 

 j boiling point of nitrogen). A change in the orientation of 

 ' the exciting rays results, not in a change in the state of 

 polarisation of each line, but a variation in the intensity 

 emitted, and this variation may vary from one line in the 

 spectrum to another. These results necessitate a modifi- 

 \ cation of the views previously admitted. — A. Cotton and 

 ; y- **outon : The absolute measurement of the magnetic 

 ; double refraction of nitrobenzene. Comparing the method 

 previously described by the authors and that of Skinner on 

 same subject, a source of error has been discovered 

 the latter, and, allowing for this, both sets of measure- 

 ^■•rnts are in good agreement. — Edmond Bauer and 

 i Marcel Moulin : The blue colour of the skv and the 

 constant of Av<^adro. According to a theorA- of Lord 

 Rayleigh, the blue colour of the skv is due to the dis- 

 persion of sunlight by the molecules of the air, and from 

 - theory an expression is deduced giving the Avogadro 

 -tant N (the number of molecules in the gram- 

 .uolecule), in terms of the ratio c/E (brightness of the 

 jsky to that of the sun), the dielectric constant of the air, 

 the apparent diameter of the sun, and other measurable 

 "T. The measurement of the ratio c/E is the most 

 NO. 2143, VOL. 85] 



difficult, too large a value being found in the presence 

 of large particles. An account is given of determinations 

 of this ratio carried out in August, 1910, at the V'allot 

 Observaton,- at the summit of Mt. Blanc. The weather 

 was unfortunately unfavourable, but the figures obtained 

 were of the same order as those of Rutherford and 

 J. Perrin, based on different considerations. The results 

 are favourable to Lord Rayleigh 's theory. — A. Laf ay : 

 The inversion of the Magnus phenomenon. — F. Michaud : 

 A capillarimeter for the measurement of the surface 

 tension of viscous liquids. The capillary tube is bent at 

 right angles, and the horizontal portion placed just under 

 the surface of the liquid. The liquid is brought to a fixed 

 mark on the horizontal portion by the pressure of an 

 indiarubber ball, and the hydrostatic pressure then 

 measured. — L. Grenet : The tempering of bronze. — M. 

 Barre : The double sulphates formed by the sulphates of 

 lanthanum and cerium with the alkaline sulphates. — 

 J. Taffanei : Safety explosives employed in mines. An 

 account of experiments carried out at the testing station 

 of the Central Committee of French Collieries. The 

 results obtained showed the importance of freeing the 

 hole from coal-dust before fixing in the cartridge ; that 

 paraffined paper as an envelope for the cartridge produced 

 injurious effects was also made clear by these experi- 

 ments. — A. Besson and L. Fournier : The reduction of 

 phosphoryl chloride by hydrogen under the influence of the 

 silent discharge. The main reaction is the formation of 

 the oxide P,0, hydrochloric acid, and water. — Marcel 

 Deldpine : The action of pyridine upon the irido- 

 disulphates. — G. Quillemin and B. Delachanal : Re- 

 search on the gases occluded in the copper alloys. The 

 metals examined included various kinds of brass, bronze, 

 phosphor bronze, and tin, and the gases were only given 

 up after fusion in a vacuum. Carbon dioxide and 

 hydrogen were present in all the metals examined, methane 

 and carbon monoxide being also present in the majority 

 of cases. — G. Darzens : A new method for the prepara- 

 tion of the glycidic esters. Ethyl dichloroacetate and 

 acetone react readily in benzene solution with magnesium, 

 a-chIor-/3-oxyisovalerianic ethyl ester being formed. From 

 this the theoretical yield of dimethylglycidic ethyl ester is 

 readily prepared in theoretical yield by treatment with 

 sodium ethylate. — Gabriel Bertrand and G. Weisvweiller : 

 The constitution of vicianose and vicianine. — Ch. 

 Maugruin : Liquid crystals in convergent light. — Med. 

 Gard : A hydrid of Fuscus platycorpus and F. ceranoides. 

 — Lucien Daniel : A perennial bean. — Jules Amar : The 

 working of the human machine. — -A. Fernbach and 

 M. Schcen : The influence exerted by the reaction upon 

 certain properties of malt extracts. The extracts were 

 made neutral to different indicators, and the resistance to 

 the effect of a rise of temperature and the increase in 

 diastatic activity after keeping were measured. — L. 

 Launoy : The toxicity of some mineral and organic com- 

 pounds of arsenic : effect of repeated non-toxic doses. — 

 Louis Legrer : The muddy taste in certain fresh-water 

 fish. — J. Deprat : The tectonic of Yun-nan. — Th. 

 Glangreaud : The western edge of the Montbrison basin. 

 — F. Qrandjean : A measure of the lamination of sedi- 

 ments (limestones and schists) by means of the tourma- 

 line crystals. 



New SoirtH W.ales. 



Royal Society, June i. — Mr. H. D. Walsh, presi- 

 dent, in the chair. — G. H. Knibbs : Note on the influence 

 of infantile mortality on birth-rate. — L. Cohen : The 

 determination of alkali in arsenical dip-fluids. — Prof. 

 A. C. Haddon : Note on Mr. L. Hargrave's paper, " Lope 

 de Vega." — T. Harvey Johnston: Australian avian 

 entozoa. — T. W. Keele : The great weather cycle. 



July 6. — Prof. T. W. E. David, F.R.S., president, in the 

 chair. — A. Duckwworth : The respective limits of Federal 

 and State legislation in regard to companies. — J. H. 

 Maiden : Records of the earlier French botanists, as re- 

 gards Australian botany. — Dr. W. G. Wooinougrh : Stone 

 rolls, in the Bulli coal seam of N.S. Wales. — Dr. J. Bur- 

 ton Cleland and T. Harvey Johnston : Worm-nests in 

 -Australian cattle due to Filaria (Onchocerca) gibsont, with 

 notes on similar structure in camels. — T. Harvey John- 

 ston and Dr. J. Burton Cleland : The anatomy and 

 possible mode' of transmission of Filaria (Onchocerca) 



