326 



NA TURE 



[March 9, 1922 



Societies and Academies. 



London. 

 Royal Society, March 2. — Sir Charles Sherrington, 

 president, in the chair. — L. N. G. Filon and H. T. 

 Jessop : On the stress-optical effect in transparent 

 solids strained beyond the elastic limit. The stress- 

 optical effect in glass under simple pressure exhibits 

 no time-effect at ordinary temperatures, but in 

 celluloid under simple tension there is a marked 

 creep in both stress-optical effect and strain even 

 under very moderate loads. The observations can 

 be explained on the assumption that celluloid consists 

 of a mixture of two constituents having different 

 elastic and plastic properties and different stress- 

 optical coefficients, the optical-effect in each being 

 strictly proportional to the stress. — ^W. E. Curtis : 

 The structure of the band spectrum of hchum. 

 Measurements of grating photographs of three of 

 the principal helium bands show that the chief 

 features of their structure are accounted for by the 

 quantum theory of band spectra. In each of the 

 three bands a new type of series is found. The 

 spectrum is considered to be due to an unstable 

 helium molecule, having a moment of inertia of 

 about I -8x10-" gm.cm.".— S. Datta : The spectrum 

 of beryllium fluoride. The spectrum of beryllium 

 fluoride consists of six groups of bands, all in the 

 ultra-violet between X 2800 and X 3400, and all 

 fading off towards the red. The strongest band at 

 X 3009 includes three series of lines, which depart 

 considerably from the usual type of formula. The 

 groups of bands are similar to one of the groups given 

 by magnesium fluoride. — W. G, Palmer : The catalytic 

 activity of copper. Pt. III. The effect upon the 

 catalytic (dehydrogenating) activity of copper of 

 adding to the metal varying proportions of weak 

 dehydrogenating catalysts, ferric, manganous, zinc, 

 and magnesium oxides, is described. Magnesium 

 and manganous oxides enhance the activity of the 

 copper, if present in quantity greater than i to 2 

 per cent., while zinc and ferric oxides reduce the 

 activity. It is considered that small proportions of 

 oxide (less than i to 2 per cent.) destroy the activity 

 of the copper, owing to solution in the metal leading 

 to diminished adsorption of the alcohol attacked. — 

 G. B. Jeffery : (i) The motion of ellipsoidal particles 

 immersed in a viscous fluid. (2) The rotation of two 

 circular cyUnders in a viscous fluid, (i) Einstein 

 has shown that the viscosity of a fluid containing 

 solid spherical particles in suspension is given by 

 jx (14-2-5 V), where /x is the viscosity of the pure 

 fluid and V is the total volume of the particles per 

 unit volume of the suspension. This result is ex- 

 tended to elUpsoidal particles and it is shown that 

 the factor 2-5 is reduced but always lies between 2 

 and 2-5 and depends upon the shape of the pai tides. 

 (2) The problem of the rotation of a circular cyhnder 

 in a fluid contained in a non-concentric cylindrical 

 vessel which may itself rotate about its axis can be 

 solved in finite terms ; that of the rotation of two 

 parallel cyhnders in an infinite fluid is in general 

 insoluble ; i.e. there is no steady motion for which 

 the fluid is at rest at infinity. 



Paris. 

 Academy of Sciences, February 13. — M. Emile Bertin 

 in the chair. — Maurice Janet : The characters of 

 the moduU of forms and systems of partial differ- 

 ential equations. — Witold Wilkosz : A fundamental 

 point in the theory of potential. — E. Cartan : A 

 geometrical definition of the energy tensor of Einstein. 

 — M. Auric : The resolution of an indeterminate 

 Hnear equation. — V. Dolejsek : The Ka Unes of the 



NO. 2732, VOL. 109] 



lighter elements. The Ka lines have been measured 

 for thirteen elements, ranging between chlorine and 

 zinc. — A. Dauvillier : The complexity of the K series 

 of the light elements and its theoretical interpreta- 

 tion. Results and details of measurements in the 

 K series of copper and molybdenum. — C. E. Guye : 

 The extension of the law of Paschen to polarised 

 fluids. — M. Mercier: Harmonic synchronisation of 

 electrical oscillators. — R. Bouloch : Calculation of 

 the elements which determine a centred system formed 

 by any number of surfaces. — A. Zimmern : The in- 

 fluence of temperature on the sensibility of emulsions 

 in radiography. Over the range 15° to 80° C. the 

 sensibility of a photograpliic plate to Ught varies 

 sUghtly, if at all. With X-rays, on the other hand, 

 the sensibility increases with rise of temperature, and 

 this effect can in some cases be utilised with advan- 

 tage. It would appear that the actions of Ught and 

 X-rays on the silver salt are dissimilar. — C. Matignon 

 and M. Frejacques : The transformation of ammonia 

 into urea. Quantitative study of the conversion of 

 ammonium carbamate into urea, alone or in presence 

 of catalysts. — Paul Pascal : The magneto - chemical 

 investigation of constitution in mineral chemistry. 

 The phosphoric acids. Measurements of the magnetic 

 susceptibilities are given, and constants deduced for the 

 groups, P, PO2, PO3, PO, and PO4. The results agree 

 with the rational formulae PO(OH)3 and RPO(OH)2 

 for the phosphonic and phosphoric acids, and are 

 opposed to H2PO(OH) for hypophosphorous acid and 

 HPO(OH)2 for phosphorous acid. — E. Decarridre : 

 The role of gaseous impurities in the catalytic oxida- 

 tion of ammonia. The influence of hydrogen phos- 

 phide. Phosphoretted hydrogen poisons the catalyst 

 (platinum) in ammonia oxidation, even in a pro- 

 portion as low as 0'00002 per cent. — Marcel Godehot 

 and Pierre Bedos : The oxide of cyclohexene and 

 ortho-methylcyclohexanol. The ether oxide of cyclo- 

 hexanol is obtained in quantitative yield by the 

 oxidation of cyclohexene with perbenzoic acid. 

 Methylmagnesium iodide reacts with the ether oxide 

 giving o-methylcyclohexanol. — V. Thomas : A mixed 

 organometallic compound of aluminium. Methylene 

 iodide reacts slowly with aluminium at the ordinary 

 temperature, no gas being evolved. — Alphonse Mailhe : 

 A new preparation of amino-naphthenes. Cyclo- 

 hexanone or its alkyl derivatives are converted into 

 ketazines by reaction with hydrazine hydrate and 

 these reduced to amines by catalytic reduction with 

 nickel. The main product consists of primary amines, 

 with a small proportion of secondary amines as a bye- 

 product. — G. Meunier : The action of mineral acids 

 on crude celluloses : the formation and destruction 

 of reducing substances. The utilisation of the bye- 

 products of this destruction. Dilute mineral acids 

 at a high temperature attack the Ugno-celluloses as 

 vigorously as strong acids, used cold, with economy 

 of acid. The bye-products include fatty acids, fur- 

 furol, acetone, and methyl alcohol, and suggestions 

 are made for their utiUsation. — Charles Jacob : The 

 structure of southern Tonkin. Except for small 

 differences in detail, the geological structure of 

 southern Tonkin is the same as that of North Annam. 

 — Mile. Yvonne Boisse de Black : Rissian erosion in 

 the high valleys of the Cdre and the Goul (Cantal). — 

 P. Monnet : The Itahan earthquake of September 7, 

 1920. A slight shock on September 6 was followed 

 on the 7th by a disastrous earthquake by reason of 

 which 250 lives were lost. The seismic zone is a 

 rough oval the major axis of which is S.E.-N.W. and 

 about 50 kilometres long. — ^C. and M. Schlumberger : 

 Electrical phenomena produced by metallic deposits. 

 It has been shown in an earUer communication that 

 deposits of pyrites produce spontaneously differences 

 of potential with the surrounding layers. The 



