May 20, 1 92 2 J 



NA TURE 



667 



Cambridge. 

 Philosophical Society, May i. — Prof. H. F. Baker 

 in the chair. — H. Lamb : Waves of permanent type 

 at the interface of two liquids. — A. E. Western : The 

 number of primes of the form «"+!. — S. Chapman 

 and T. T. Whitehead : The influence of electrically 

 conducting material within the earth on various 

 phenomena of terrestrial magnetism. — Mr. Ince : The 

 impossibility of the coexistence of two Mathieu func- 

 tions. — V. Trkal : A general condition for the quant- 

 isation of the conditionally periodic motions with an 

 application for the Bohr atom. — C. D. Ellis : Inter- 

 pretation of the )3-ray and 7-ray spectra. Taking a 

 general view of a ;8-ray disintegration and of the 

 radiations that accompany it, the ^-ray line spectrum 

 is entirely secondary in origin and due to the con- 

 version of monochromatic 7-rays. The general /3-ray 

 spectrum and these 7-rays are the primary phenomena. 

 This theory accounts for the thorium- C and radium-Z) 

 spectra. Frl. Meitner's theory is unlikely to be cor- 

 rect ; it offers no explanation of the general ;8-ray 

 spectrum ; it predicts that the total number of 

 electrons emitted should be less than the number of 

 atoms disintegrating ; and, finally, certain hnes in the 

 radium- B spectrum should be primary and charac- 

 teristic of the radium- B nucleus and therefore should 

 not appear in the spectrum excited in lead by the 

 7-rays of radium- 5. These lines, however, have been 

 observed. 



Dublin. 



Royal Dublin Society, April 25. — Dr. G. H. Pethy- 

 bridge in the chair.— W. E. Adeney, A. G. G. Leonard, 

 and Miss A. M. Richardson: On the aeration of 

 quiescent columns of distilled water and of solutions 

 of sodium chloride. Columns of de-aerated distilled 

 water and of sodium chloride solutions up to ten feet 

 in length were exposed to a slow current of dry 

 air for periods of 14-56 days. Samples were with- 

 drawn from various depths and the nitrogen content 

 determined. It is found that aeration is effected 

 by the exposed layer mixing with the unexposed 

 portions of the water to depths of at least 10 feet. 

 This process is caused by the downward " streaming " 

 by the constantly changing layer of water exposed 

 to the air. It proceeds more rapidly, and more 

 uniformly, to depths of at least 10 feet, in salt water 

 than in fresh water. The rate at which " streaming " 

 proceeds depends largely upon the rate at which the 

 concentration and cooling of the surface layer is 

 brought about by evaporation, and proceeds more 

 rapidly at temperatures at and above 10° C. than 

 below it. It is less rapid, and less uniform downwards 

 to 10 feet deep, and probably to greater depths, at 

 temperatures below 8° C, especially in fresh waters. 

 The rate of mixing also depends upon the concentra- 

 tion of salt in solution. The optimum concentration 

 appears to be about i per cent, sodium chloride. — 

 T. A. McLaughlin : Cataphoresis of air bubbles in 

 various hquids. Air bubbles show no cataphoresis 

 in the following liquids : methyl, ethyl, and butyl 

 alcohols, xylol, benzine, toluene, bromobenzine, 

 benzyl alcohol, benzaldehyde, aniline, cinnamic alde- 

 hyde, ethyl malonate, lactic acid, oleic acid, ethyl 

 acetate, and turpentine. It was not possible to trap 

 an air bubble in acetone and volatile liquids such as 

 carbon disulphide. In impure acetone foreign matter 

 moved towards the positive pole . I n distilled water, air 

 bubbles moved towards the positive pole ; in impure 

 benzine, towards the negative pole ; in " pure " 

 nitrobenzine, to the negative pole. In impure nitro- 

 benzine the motion may be to either pole. 



Paris. 

 Academy of Sciences, April 24. — M. Emile Bertin 

 in the chair. — E. Goursat : The theory of integral 

 invariants. — P. Marc^al : The metamorphosis of the 

 females and hypermetamorphosis of the males in the 

 Coccidia of the Margarodes group. Both males and 

 females pass through three forms — first a primary' 

 hexapod larva capable of migration ; then a cystoidal 

 larva adapted to life fixed to a plant ; and, thirdly, a 

 hexapod form, at which stage the development of the 

 female is arrested. The male continues to develop 

 through two or three other forms before reaching the 

 winged stage. — L. Lumiere : Capillary movement, 

 diffusion, and displacement. A study of flow through 

 filter paper and cotton strips used as siphons. The 

 flow of liquid increases with the height of fall up to 

 a certain distance and then remains constant. Some 

 practical applications are given, including washing 

 photographic negatives and precipitates with mini- 

 mum quantities of water. A negative 9 cm. by 12 cm. 

 can be washed completely in 15 minutes with less 

 than 30 c.c. of water. — E. Vessiot : Surfaces generated 

 by circles. — E. Cartan : The equations of structure 

 of generalised space and the analytical expression of 

 Einstein's tensor. — E. Norlund : The interpolation 

 formula of Newton. — B. Gambler : Point correspond- 

 ence of two surfaces and a class of surfaces analogous 

 with isothermal surfaces. — A. Pictet and J. H. Ross : 

 The polymerisation of laevoglucosane. Laevoglu- 

 cosane, heated to 140° C. in the presence of a trace 

 of zinc chloride, polymerises in accordance with the 

 equation wCjHioOj = (CgHioOj), in a few minutes. 

 Different polymers are obtained by varying the pres- 

 sure : at 15 mm. of mercury w = 2 and the product 

 is dilaevoglucosane (C,Hio05)2, at atmospheric pres- 

 sure « = 4, under 4-6 atmospheres w = 6, and at 13-3 

 atmospheres « = 8.— P. Gaubert : The liquid crystals 

 of calcium phosphate. — P. L. Mercanton : The mag- 

 netic state of arctic basalts. Since the Tertiary period 

 the magnetic inchnation of the earth in the northern 

 regions would appear to have changed its sense : to 

 complete the proof an examination of antarctic larvas 

 is desirable. — S. Stefanescu : The phylogeny of Ele- 

 phas antiquus. — A. Carpentier : The conifers and ferns 

 of the Weald of Feron-Glageon.— J. Maheu : A re- 

 tarded regeneration of moss. A detailed description 

 of the growth of a specimen of Barhula muralis, after 

 remaining 14 years in a state of absolute dryness. — • 

 G. Nicolas : Remarks on Narcissus tazetta. — G. 

 Malfitano and M. Catoire : Amylocellulose considered 

 as a compound of sihcic acid and amylose. Experi- 

 mental evidence that sihca is an essential constituent 

 of amylocellulose. — A. Vila : The influence of heat 

 and of some solvents on the viscosity of horse serum. 

 The coagulating effect of acetone, analogous with 

 that of heating, can be reduced or even avoided alto- 

 gether by taking certain precautions. — Y. Manou^lian : 

 Histo-microbiological researches on general paralysis. 

 Existence of the treponeme in the cytoplasm of the 

 nerve cells of the cerebral cortex. 



Official Publications Received. 



Annual Report of the Academy of Xatural Sciences of Philadelphia 

 for the Year ending November 30, 1920. Pp. 57+6 plates. (Phil- 

 adelphia.) 



Proceedings of the Academy of Natural Sciences of Philadelphia. 

 Vol. 73, Part 2, 1921. Pp. 193-435+ plates 9-47. (Philadelphia.) 



State of Connecticut. Public Document No. 47. State) Geological 

 and Natural History Survey. Vol. 6, Bulletin8i23-32,» 1915-1920. 

 (Hartford.) 



CarnegiellnBtitution of Washington. Annual Beport'of the Director 

 of the Department of Terrestrial Magnetism. (Extracted from Year 

 Boole No. 20 for the Year 1921.) Pp. 307-357. (Washington.) 



Jahrbiicher der Zentralanstalt fur|Meteorologie und Geodynamik. 

 Amtliche-^Veroffentlichung. Jahrgangll917. Neue rolge,v54 Band. 

 Pp. xx^111+A24 + B38 + C41+D22 + E6+F18+G38. (Wien : Gerold 

 undjKomp.) 



Leeds University. Seventeenth Report, 1920-21. Pp.166. (Leeds.) 



NO. 2742, VOL. 109] 



