258 



NATURE 



[February 23, 1922 



electrons in any direction making an angle with that of 

 the incident radiation will not be in phase. Measure- 

 ment of the intensity of the radiation scattered in 

 different directions gives the diffraction pattern for 

 the atom. The Ka doublet of rhodium falling on 

 a crystal shows that each electron in the atom 

 scatters independently. On the average, three or four j 

 electrons lie in the region near the edge of the atom, 

 and the main concentration is much closer to the 

 nucleus. 



November 15.— Mr. R. L. Taylor, vice-president, 

 in the chair. — S. Chapman : Certain integrals oc- 

 curring in the kinetic theory of gases. In the kinetic 

 theory of gases, if molecules are regarded as point- 

 centres of force, the calculation of the intensity of the 

 force from exp>erimental determinations of gaseous 

 viscosity depends upon numerical factors which have 

 not hitherto been evaluated except in one case. The 

 factors concerned have now been calculated in other 

 cases. — ^J. E. Jones : The dynamics of collision of 

 diatomic molecules. By the application of Maxwell's 

 kinetic theory, a simple relation between the velocity 

 with which the points of contact approach each other 

 and the velocity with which they separate has been 

 found ; a simple relation between the impulse acting 

 on each body at collision and the velocity of approach 

 of the points of contact has been deduced and the 

 impulse on collision calculated. The velocities after 

 collision are then deduced from the ordinary dynamical 

 equations of momentum. 



Paris. 

 Academy of Sciences, February 6.— M. Emile Bertin 

 in the chair. — L. Lecornu : Some remarks on rela- 

 tivity. — M. Hamy : The determination by interference 

 of the diameters of stars the superficial brightness of 

 which is not uniform.— C. Richet, E. Bachrach, and 

 H. Cardot : The tolerance of the lactic ferment to 

 poisons. It has been shown that the lactic acid 

 organism gradually grows accustomed to poisons 

 present in the culture media. It is now proved that 

 this is specific, in the sense that a ferment grown 

 tolerant to the presence of one poison still remains 

 sensitive to another. The lactic ferment may be made 

 to tolerate the presence of two different poisons simul- 

 taneously.— F. Widal, P. Abrami, and J. Hutinel : Re- 

 searches on the proteopexic insufficiency of the liver 

 in dysenteric hepatitis. The test previously described 

 by the authors (enumeration of the white blood 

 corpuscles after drinking a glass of milk, fasting) 

 proves whether the liver is completely arresting in- 

 completely disintegrated proteids, and this has proved 

 to be a most sensitive test of the proper functioning 

 of the liver. In dysentery the liver may be exten- 

 sively attacked without affecting the proteopexic 

 function.— M. d'Ocagne : The comparative examina- 

 tion of various nomographic methods.— A. de Gramont 

 and G. A. Hemsalech : The evolution of the spectrum 

 of magnesium under the influence of increasing elec- 

 trical actions. Applications to astrophysics. From a 

 detailed study of the effects of temperature and of the 

 strength of the electric field on the lines of the magnesium 

 spectrum various conclusions of interest in astrophysics 

 are drawn. It is dangerous to conclude that a star 

 possesses a high temperature because the spark-lines 

 predominate in its spectrum. It is important to study 

 the character of each line. — C. Guichard : Networks 

 which are several times Q.o"-~~"J- Timmermans, Mile. 

 H. Van der Horst, and H. Kamerlingh Onnes : The 

 melting points of pure organic liquids as thermometric 

 standards for temperatures below 0° C. The tem- 

 peratures were determined by a platinum resistance 

 thermometer, standardised against the helium thermo- 

 NO. 2730, VOL. 109] 



meter, of nine carefully purified liquids. The range 

 covered is between - 159-6° C. (isopentane) and 

 -22-9° C. (carbon tetrachloride), with an error of 

 less than 01° C. Specimens of these standard liquids 

 will be distributed to other institutions later on. — M. 

 Gevrey : Remarks on quasi-analytical functions. — G. 

 Julia : Series of rational fractions and integration. — 

 T. Carleman : A theorem of M. Den joy.— G. Sagnac : 

 The projection of the light of periodic double stars- 

 and the oscillations of the spectral lines. — D. Coster : 

 The L series of the X-ray spectrum. The X-ray 

 spectra of a large number of elements (from Ta 

 to Rb) have been remeasured. In general, the new 

 results confirm earlier work, and also give support 

 to the theory of structure of the Bohr atom. Details 

 are given in cases where the new measurements are 

 not in agreement with the earlier observers. — M. 

 Bedeau : Measurement of the dielectric constant of 

 gases .and vapours by means of circuits with sustained 

 waves.— C. E. Guye and R. Riidy : A new mode of 

 determination of the molecular diameters by the 

 electromagnetic rotation of the discharge in the gases. 

 Earlier work had shown that whilst the molecular 

 diameters obtained by this formula were of the same 

 order of magnitude as those obtained by the viscosity 

 method, the results were greatly influenced by the 

 presence of traces of impurities. In the present work 

 great care was taken in the purification of the gases, 

 and comparative figures for the molecular diameters 

 obtained by the electromagnetic rotation and the vis- 

 cosity methods are tabulated for oxygen, nitrogen, 

 carbon dioxide, hydrogen, nitrous oxide, methane, and 

 carbon monoxide. The two sets are in fair agree- 

 ment. — L. Guillet and J. Cournot : The variations of 

 the mechanical properties of metals and alloys at 

 low temperatures. Results are given for the resilience 

 and Brinell test at 20° C, -20° C, -80° C, and 

 -190° C. of electrolytic iron, steels, and alloys. — P. 

 Jolibois and R. Bossuet : The relations between the 

 different oxides of uranium. At 500° C. in a vacuum 

 the oxide UO3 loses oxygen, giving rise to U^Og, and 

 the reaction is irreversible. The same oxide is formed 

 by heating UO^ In oxygen. — P. Lebeau : The oxides 

 of uranium. The only oxides of uranium which have 

 a certain existence are UO,, U,Og, and UO,. The 

 green oxides prepared at temperatures below 800° C. 

 contain variable quantities of uranic anhydride, and 

 change in composition in contact with moist air. — H. 

 Pelabon : The action of selenium on gold. Gold is 

 slightly attacked by selenium ; the metal fixes a little 

 selenium, and the selenium Itself takes up a little 

 gold. — E. Grandmougin : Some new derivatives of 

 sulphobenzide. — G. Dupont : The composition of 

 Aleppo essence of turpentine. This turpentine con- 

 tains q5 per cent, of pinene, 1-14 per cent, of Inactive 

 bornvl acetate, and 3-8 per cent, of sesquiterpene.— 

 G. Mouret : The eastern limit of the granitic massif 

 of Mlllevaches.— P. Glangeaud : • The Saint-Flour 

 Ollgocene basin. The Miocene Truyere flowing into 

 the AUIer. — P. Negris : Glacial phases In Greece. — R. 

 Bourret : The strata in the north-east of Tonkin. — T-. 

 Dussault : The geology of western Tonkin. — E. 

 .Saillard : Composition of the wild beetroots. — R. 

 Stumper : New observations on the poison of ants. 

 The concentration of the formic acid in Formica rufa 

 was found to varv between 21 and 73 per cent, of 

 pure acid. Formic acid Is alwavs present In the 

 Camponotlnae. but absent in Myrmicinae and Dollcho- 

 derinae.^ — M. Doyon : The Incoagulability of the cir- 

 culating blood provoked in the frog by iniections of 

 nucleic acids. Duration of the phase. Comparison 

 with various anti-coagulants. — A. A. Mendes-Correa : 

 The asymmetry of the skeleton of the upper 



