| ee ae 
[ARCH 17, 1923] 

Paris. 
Academy of Sciences, February 19.—M. Albin 
Haller in the chair—G,. Urbain: Celtium, element of 
atomic number 72. A discussion as to the priority 
of Coster and Hevesy. The author cites the earlier 
work of Dauvillier and himself, and concludes that 
Coster and Hevesy were not the discoverers of 
element 72, but have only found a material in which 
it is present in a relatively high proportion. The 
author claims that the name celtium has priority 
over hafnium for this element.—J. L. Breton: Spark- 
in which the spark in a gaseous dielectric is 
deflected by a strong air current. Two types of 
spark-gap are described. The simpler of the two 
consists of a conducting disc of metal or graphite 
rotating with a high velocity in a hermetically closed 
cylinder filled with coal gas or the vapour of alcohol. 
The sparks play between this disc and two graphite 
electrodes. Long uninterrupted working is secured 
by water-cooling or bya fan. The apparatus has been 
successfully applied to the working of a high - fre- 
quency-induction furnace.—Jules Andrade: Isochron- 
ism and quadratic friction.—Georges Friedel ; Choles- 
teric bodies —C. Sauvageau : The prolonged quiescent 
state of an ephemeral Alga (Mesogloia)—M. W. C. 
Brégger was elected a foreign associate in the place of 
the late M. Schwendener.—A. Myller: Systems of 
curves on a surface and the parallelism of M. Levi- 
Civita—M. Juvet: A generalisation of Jacobi’s 
theorem.—M. Malaval: Permanent deformations by 
extension and compression.—M. Mesnager : Observa- 
tions on the preceding note—P. Dumanois: An 
aerodynamical arrangement for testing motors. The 
usual fan resistance does not permit of continuous 
variation. The author encloses the fan in a cylindrical 
drum closed by two plane parallel walls, one of which 
is constructed of radiating shutters. By partially 
opening the shutters, when fixed toa 12 h.p. motor, 
e number of turns per minute can be varied between 
950 and 1470, a sufficient variation for practical con- 
ditions of use.—M. Rateau: Remarks on the preced- 
ing communication. M. Dumanois’ apparatus has 
advantages over the Froude brake.—A. Weinstein : 
The unicity of sliding movements.—Charles Bohlin : 
The autologous series belonging to the problems of 
two and three bodies.—Ernest Pasquier: A simple 
expression of the acceleration of mercury in the case 
of the problem of two bodies, taking into considera- 
tion the movement of the perihelion of the planet.— 
Thadée Peczalski: The relation between Young’s 
modulus and the ratio of density to atomic mass. 
The relation E=B(s/M)? is deduced, in which E is 
Young’s modulus, 6 is the density, M the atomic mass, 
and B a constant (8x 10° kilograms per sq. mm.). 
The calculated and experimental values are compared 
for nine metals——A. Marcelin: Superficial fluids. 
The unlimited extension of oleic acid. A study of the 
“ superficial pressure’ exerted by a thin layer of 
oleic acid on water. When the layer of oleic acid is 
one molecule thick the acid may be regarded as being 
in an intermediate state between the free and dis- 
solved states, to which the name of “ superficial 
solution ”’ is given.—St. Procopiu: The appearance of 
the flame, are and spark lines in the arc-spectra of 
metals in a vacuum.—Albert Portevin and Francois 
Le Chatelier: A phenomenon observed during the 
test by extension of alloys in course of transforma- 
tion. The peculiarity observed was confined to 
aluminium alloys of the duralumin type with or 
without the addition of other metals (manganese, 
zinc). The elongation of the test pieces, instead of 
increasing continuously with the pull, progressed by 
repeated oscillations of an amplitude amounting to 
4 per cent. of the load and with a frequency of several 
NO. 2785, VOL. 111] 

NATURE 

383 
oscillations per second. The phenomenon attained 
its maximum amplitude pipe eho tempering. 
—A. Bigot: The action of heat on kaolins, clays, etc. 
Black pottery. A study of the black pottery from 
the Bouchets Cave (Ardéche), from Basutoland, and 
of Etruscan black vessels—André Brochet: The 
hydrogenation and dehydrogenation of castor oil and 
its derivatives. Castor oil with active nickel was 
treated with hydrogen at 150°C. under pressure. The 
pressure showed a series of oscillations which can be 
interpreted by assuming a series of hydrogenations 
and dehydrogenations. The fully hydrogenated pro- 
duct gave off hydrogen on heating with nickel to 
about 280°, but the product finally obtained did not 
correspond with the original oil—René Locquin and 
Sung Wouseng: the hydration of the dialkylethinyl- 
carbinols and the preparation of the «-hydroxy- 
methyl ketones. Tertiary acetylenic alcohols of the 
type RR.C(OH).C=CH are readily converted into 
the ketones PR .C(OH) .CO.CH, by Denigés’ reagent 
(acid sulphate of mercury). Details of the method 
are given and a description of five ketones prepared 
by this general method.—Henry Joly : Stratigraphical 
observations on the Oxfordian and Lusitanian at 
certain points in the Celtiberic chain (Spain).—Léon 
Bertrand and Antonin Lanquine: The large Pro- 
vencal sheets of Audibergue and Cheiron (Maritime 
Alps).—E. Schnebelé: The present structure of the 
primary Vosges. The application to the whole of the 
Vosges of observations made especially to the north 
of the valley of Villé—L. Giraux: The geological 
position of the neolithic workshops of the forest of 
Montmorency.—J. Beauverie: The relations existing 
between the development of wheat rust and climate. 
The sharp contrast between the climatic conditions in 
1921 and 1922 showed that Puccinia triticina 1s 
especially the rust of dry seasons and P. graminis 1s 
the rust of wet seasons, the latter doing the most 
damage from the point of view of yield of grain.—M. 
Rose, J. Dragoiu, and F. Vlés: The reversibility of the 
phenomena of arrest by lowering the pH in the 
evolution of the eggs of the sea urchin.—M. and Mme. 
G. Villedieu—The action of insoluble oxides on the 
mildew of potato (Phytophthora infestans). It is 
generally admitted that for a substance to act on a 
living organism it must first be rendered soluble. 
Experiments on the toxic action of the insoluble 
oxides of various metals (magnesium, cadmium, 
nickel, cobalt, zinc, copper, mercury) on the conidia 
of potato mildew are in direct contradiction with this 
hypothesis.—R. Herpin: Comparison between the 
sexual behaviour of some nereidians from the coasts of 
the Channel.—Ch. Gravier : Remarks on the preced- 
ing communication.—Auguste Lumiére: The possi- 
bility of realising intestinal disinfection. An account 
of some experiments with sodium argentothiogly- 
cerine sulphonate, AgS . CH, .CH(OH). CH, .O. SO;Na. 
Experiments on a dog showed that while a dose of 
1 gm. of benzonaphthol per day had no effect on the 
number of organisms in the fecal matter, the ad- 
ministration of the same weight of the silver com- 
pound sterilised the intestine in four days. 



Official Publications Received. 
Report of the Canadian Arctic Expedition, 1913-18. Vol. 6: Fishes 
and Tanicates, Part B: Ascidiacea, (Southern Party, 1913-16.) By A. 
G. Huntsman. Pp.14. Vol. 7: Crustacea, Part G: Euphyllopoda. By 
Frits Johansen. Pp. 34 Part N: The Crustacean Life of some Arctic 
Lagoons, Lakes, and Ponds. (Southern Party, 1913-16.) By Frits 
Johansen. Pp. 31. Vol. 8: Mollusks, Echinoderms, Ccelenterates, etc. 
Part G: Alcyonaria and Actinaria. By Prof. A. E. Verrill. Pp. 164. 
Part I: Hydroids. By C. McLean Fraser. Pp. 5. (Ottawa.) 
Minutes and Proceedings of the Institution of Civil Engineers ; with 
other Selected Papers. Edited by Dr. H. H. Jeffeott. Vol. 214. Pp. 
iv+3862+6 plates. (London: Gt. George Street.) 
