July 29, 1920] 



NATURE 



699 



Societies and Academies. 



Paris. 

 Academy of Sciences, July \z. — M. Henri Deslandres 

 in the chair.— L. Maquenne and E. Demoussy : The 

 catalytic action of copper salts on the oxidation by air 

 of ferrous compounds. Copper salts accelerate the 

 oxidation of ferrous salts by air, even in dilutions so 

 great as 02 mgr. of copper per 100 c.c. of solution. 

 The amount ot oxidation depends on the nature of 

 the acid present, and is in direct relation with the 

 degree of hydrolytic dissociation.— P. A. Dangeard : 

 Vacuome, plastidome, and spherome in Asparagus 

 verticillaius.—¥. Widal, P. Abrami, and M. N. 

 lancovesco : The possibility of promoting the haemo- 

 clasic crisis by the intravenous injection of portal 

 blood collected during the digestive period. The 

 action of the liver on the proteids of incomplete dis- 

 integration arising from digestion and carried by the 

 portal vein. An experimental proof that the gastro- 

 intestinal mucous membrane absorbs not only amino- 

 acids, but also compounds in which the proteolysis is 

 incomplete. These products are present in the portal 

 vein for about two hours and a half after a meal, and 

 their injurious action upon the general circulation is 

 prevented by the liver.— H. de Chardonnet : The 

 influence of the American rocking-chair upon the 

 respiration. — J. A, L. Waddell : The economical use 

 of special alloy steels in the construction of bridges. 

 The higher elastic limit of a special steel compared 

 with that of an ordinary carbon steel may more than 

 compensate for the increased price. Some detailed 

 examples are given. — C. E. Guillaume : The anomaly 

 of elasticity of the nickel steels : The realisation of 

 an elinvar and its application to chronometry. The 

 limitations of nickel steel watch-springs are discussed, 

 and a new ternary nickel-chromium steel alloy sug- 

 gested, containing chromium with small quantities of 

 manganese, tungsten, and carbon equivalent to 12 per 

 cent, of chromium. The results with springs of this 

 material used with a balance-wheel made of a single 

 metal have proved extremely satisfactory. The 

 change of temperature from 0° C. to 30° C. with a 

 watch fitted with one of these springs was two seconds 

 in twenty-four hours, and the rate was practically a 

 linear function of the temjaerature.— G. Fubini ; Pro- 

 jectively applicable surfaces. — L. E. J. Brouwer : 

 Enumeration of the classes of representations of a 

 surface on another surface. — M. Galbrun : The ap- 

 plication of the equations of elasticity to the deforma- 

 tions of a helical spring. — P. Chevenard : Study of the 

 elasticity of torsion of nickel steels with a high pro- 

 portion of chromium. A study of three series of ferro- 

 nickels containing approximately 5, 10, and 15 f>er 

 cent, of chromium. The results are given graphically 

 in three diagrams. — E. Jouguet : Remarks on the 

 laws of resistance of fluids. — G. Sagnac : The two 

 simultaneous mechanics and their real connections. — 

 M. Panthenier : Study of the ratio of the absolute 

 retardations in carbon bisulphide for increasing, dura- 

 tions of charge. The appearance of electro-striction. 

 When the duration of the charge of the Kerr con- 

 denser much exceeds a millionth of a second, the ratio 

 of the retardations in carbon bisulphide is no longer 

 equal to —2. The contraction of the liquid under the 

 influence of the electric field, electro-striction, com- 

 plicates the results ; when the time of change is 

 8-IXIO-* seconds, the effect of electro-striction 

 exactlv compensates the double refraction for the 

 vibrations perpendicular to the field. — C. Florisson : 

 The galena-metal contact rectifier. .Artificial increase 

 of sensitiveness. — H. Weiss : The constituents formed 

 by reciprocal penetration of zinc and copper at a 

 temperature where one of the two metals and all 

 NO. 2648, VOL. 105] 



their alloys are in the solid state. The constant tem- 

 perature required for these experiments was secured 

 by the use of a sulphur vapour bath under a reduced 

 pressure, the temperature thus obtained varying only 

 at most 1° from 410° C. Micrographic methods 

 were used for studying the resulting alloys, and two 

 photographs illustrating the results are reproduced. — 

 MM. Lespleau and Uarreau : The phenylpropines. 

 The reaction between benzyl chloride and the mono- 

 sodium derivative of acetylene failed to give benzyl- 

 acetylene, the isomer phenylmethylacetylene being the 

 only product. The same substance was obtained by 

 starting with epidibromohydrin and phenylmagnesium 

 bromide and treating the resulting compound, 

 C.H^-CH.-CBrlCH,, with alcoholic potash. A yield 

 of 40 per c^t. of the desired benzylacetylene was 

 obtained by the interaction of phenylmagnesium 

 bromide and propylene tribromide.- — G. Mignonac : The 

 catalytic hydrogenation of nitriles : mechanism of the 

 formation of secondary and tertiary amines. The 

 best explanation of the secondary reduction products 

 arising from the reduction of benzonitrile by hydrogen 

 in presence of nickel and working in an anhydrous 

 liquid is that the primary reduction product is 

 benzaldimine, CeHj-CHINH. This can give benzyl- 

 amine by direct reduction and benzalbenzylamine by 

 condensation, and the latter compound has been 

 isolated in quantity. — G. Zeil : The proportional con- 

 stant relating seismic frequency with rainfall. — R. 

 Abrard : The geological constitution of Djebel Tselfat, 

 Western Morocco. — G. Arnaud : A bacterial disease of 

 ivy, Hedera helix.— C. Porcher : Milk and apthous 

 fever. Comparisons of the quantity and quality of the 

 milk from apthous teats of a cow when the milk is 

 retained and drawn off.— A. Vandel : Reproduction of 

 the Planaria and the meaning of impregnation in these 

 animals. — M. de Laroquette : Analogies and differ- 

 ences of biological action of the various parts of the 

 solar spectrum. — C. Perez: A new Cryptoniscian, 

 Enthylacus trivinctus, an intrapalleal parasite of a 

 Sacculina. A case of parasitism of the third degree. 

 — J. Dragoiu and M. Faur^-Fremiet : Histogenesis and 

 time of appearance of different pulmonary tissues in 

 the sheep.— G. Bertrand and Mme. Rosenblatt : Does 

 chloropicrin act upon soluble ferments? From ex- 

 periments carried out with sucrase (from yeast and 

 from Aspergillus niger), amygdalinase, urease, cata- 

 lase, zvmase, laccase, and tyrosinase, it was found 

 that chloropicrin exerts only a feeble inhibiting action 

 on soluble ferments, and some other explanation rrrust 

 be found for its highly toxic action upon living cells. 



Cape Town. 



Royal Society 0! South Africa, June 16.— Dr. A. Ogg, 

 vice-president, in the chair. — L. Piringuey : Note on a 

 recent discovery of stone implements of Palaeolithic 

 tvpe throwing light on the method of manufacture in 

 South Africa. The author described a collection of 

 Palaeolithic stone implements from the Montagu 

 Caves, and showed that the completed implement is 

 flattened, rounded at one end and tapering to a point 

 at the other, and being chipped to a sharp edge all 

 the way round. From this demonstration it is now 

 possible to pronounce that many of the implements 

 so far known which are blunt at one piirt or another 

 are unfinished or damaged specimens. Further, it is 

 shown that a large block was chipped down in order 

 to form a relatively small delicately worked imple- 

 ment, and the very large chipped stones that have 

 sometimes been found are seen to he initial stages in 

 the manufacture.— W. A. Jolly : The reflex times in 

 Xenopus laevis. The author described his method of 

 measuring exactlv the reflex times in the reflexes from 

 the limbs of the South African clawed frog or toad, 



