304 



NA TURE 



[August 25, 1923 



Societies and Academics. 



Paris. 



Acidemy of Sciences, July 23. — M. Albin Haller 

 in tlie chair. — H. Deslandres : Mountain observatories. 

 A description of the lieights, position, and equipment 

 of the existing mountain observatories. The four 

 American observatories (Lick, Arequipa, Flagstaff, 

 Mount Wilson) can be occupied all the year round, 

 are equipped with large instruments, and have already 

 produced important results : of the others, those 

 on Mont IManc, Pic du Midi, and Etna are insufficiently 

 equipped and observations can be made only for a 

 short period of the year. For a new French 

 observatory Revard (near Aix-les-Bains) a.id Fort 

 Romeu (Pyrenees), altitudes 1500 metres and 1800 

 metres respectively, have been examined. Fort- 

 Romeu possesses the advantages of possible occupation 

 all the year round and ease of access. — G. Bigourdan : 

 The use of a completely free pendulum as a chrono- 

 meter. — F. E. Fournier. The forms of hull most 

 favourable to high speeds are only realised in racing 

 automobiles. — de Siguier. Linear groups with bi- 

 linear or quadratic invariant in the real and complex 

 field. — S. Sanielevici. An application of the tensorial 

 calculus. — Evans. Poisson's integral. — F. H. van den 

 Durgen : Some technical applications of integral 

 equations.— Emile Belot : An attempt at the re- 

 presentation of the period of continuous evolution, 

 /, of the stars as a function of the effective temperature, 

 0. Application to the sun. — R. Jarry-Desloges : The 

 influence of the various elements of an objective 

 (aperture, focal distance, magnification) on the 

 quality of telescopic images. Diaphragms smaller 

 than two-thirds of the diameter of the objective 

 cannot be usefully employed. As regards magnifica- 

 tion there exists an optimum focal length of the 

 refractors, between 6 and 6" 73 metres : this result is 

 new and dififtcult to explain. — E. Selety: The possibility 

 of an infinite potential, and of a mean velocity of all 

 stars equal to that of light. — Wladimir de B61aevsky : 

 A problem of elasticity in polar co-ordinates. — Th. 

 De Donder : Synthesis of the gravific. — Camille Gillet : 

 Aqueous solutions. The origin of osmotic effects. 

 Starting with the assumption that water is a mixture 

 in equilibrium of hydrol (HgO), dihydrol (H20)2 and 

 of poly hydrol (HjO),,, of which the first is gaseous, 

 a theory is developed affording an explanation of the 

 existence of osmotic pressure, flocculation of solutions 

 and of sols by electrolytes, the flocculation of sols by 

 other sols, and the formation of emulsions. — A. 

 Boutiric and M. Vuillaume : Study of the absorption 

 spectrum of sols of arsenic sulphide. — Alfred Gillet : 

 Researches on electrodiflfusion (migration of the ions). 

 Experiments on the migration of the ions in jellies 

 (gelatine) containing sodium sulphate. A. Lassieur : 

 The electrolytic estimation of antimony. If a thin 

 coating of mercury is deposited on the cathode, and' 

 the potential not allowed to go over i"3 volts, the 

 antimony subsequently deposited electrolytically is 

 coherent and accurately corresponds with the weight 

 of metal present. — L. J. Simon : The sulphochromic 

 oxidation of the aromatic hydrocarbons and the 

 present conception of graphite. Comparison of the 

 oxidation of aromatic hydrocarbons by sulphuric 

 acid with chromic acid and silver bichromate, together 

 with the results of the application of the silver 

 bichromate reagent to various forms of carbon and 

 coal. — L. S. Glichitch : The estimation of easily 

 dehydrated alcohols in essential oils. The estimation 

 of free alcohols in essential oils by acetylation fails in 

 the case of certain alcohols, water being removed and 



NO. 2808, VOL. 112] 



hydrocarbons formed. Hy replacing acetic anhydrid 

 by a mixture of this sulwtance with formic acid, tin 

 diflficulty is overcome.— J. Orcel : The bavalite ■ 

 Bas-Vallon, — — Thi^baud : Researches on X\ 

 mineralogical composition of s<ime chalk marls of tl 

 Tertiary of Alsjicc. — A. ChoUey : Evolution of tl. 

 karstic relief of the ParmcLin (Pr^aljxrs de Sav< !■ 

 Henri Coupin : The suppo.sed formation of cl 

 phyll in the dark. Exixjriments are 

 contradicting the view that etiolated ] 

 manufacture chlorophyll in the dark. — Jem tfKiixu 

 The formation of a glucoside (saponarine) in tl 

 mitochondria. — A. Demolon and P. Boischot : Ti 

 activity of the biological phenomena in jwat. Tl. 

 relative passivity of peat from the biological point • 

 view is clue to the poverty of the medium in nutriti\ 

 elements, and especially phosphoric acid, and tl 

 results of the partial sterilisation of peat by he. 

 cannot be attributed to destruction of toxins or t 

 an action on the protozoa. — A. Quidor and Marcel .\ 

 Herubel : The psycho-physiology of visual phenomen 

 — Paul Benoit : The polar globules of the egg ■ 

 Tiibitlaria mesembryanthemnm. — Jean Camus, J. i 

 Gournay, and Fiterre : The mechanism of insij/: 

 diabetes. — E. Lesne, L. de Gennes, and Guillaumin 

 The action of light on the variations of calcemia m 

 rickets. — A. Juillet : Remarks on the note by MM. 

 Chevalier and Mercier on the pharmacodyamic action 

 of the insecticidal principle of pyrethrum flowers. 



Sydney. 



Linnean Society of New South Wales, June 27. — 

 Mr. A. F. Basset Hull, president, in the chair. — G. L 

 Playfair : Notes on freshwater algae. A series of 

 miscellaneous notes on algae, in which twelve species 

 and fourteen varieties are described as new ; and 

 remarks made on the development and life-histor\ 

 of many species. — Miss M. I. Collins : Studies in tl. 

 vegetation of arid and semi-arid New South Walc> 

 Part i. The plant ecology of the Barrier District. 

 The paper consists of an introductory section in whic' 

 the chief physiographic units of New South Wales ai 

 discussed in reference to the formation of the Greai 

 Western Plains. The geologic, physiographic, and 

 climatic features of the Barrier Range are described, 

 accompanied by an account of the chief plant 

 associations, and lists of species for the different 

 habitats. In a final discussion the developmental 

 relationships of the associations are indicated.— 

 Miss Marguerite Henry : A monograph of tl 

 freshwater Entomastraca of New South Wale- 

 Part iii. Ostracoda. This paper gives brief di 

 scriptions of thirty-six species of Ostracods, with thci. 

 synonymy and keys for their identification. Seven 

 species are described as new, two are recorded for the 

 first time in AustraUa and one for the first time in 

 New South Wales. A freshwater member of the 

 family Cytheridae is recorded for the first time in 

 Australia. Lists are also given of the species that 

 are known to occur in other States. 



Official Publications Received. 



United States Department of Agriculture. Department BoUttii. 

 No. 1165: Report on Bird Censuses in the Unit«l Sutes 1916 to 1*.'- 

 By May Tliacher Cooke. Pp. 3(5. (Washington; Government Priuti: 

 Office.) 5 cents. 



University of Liverpool : Tidal Institute. Fourth Annual Bepoi • 

 1923. PJp. 7. (Liverpool.) 



University of Colorado Bulletin. VoL 28, No. 8, General Series N 

 192 : Catalogue, 1922-1923, with Announcements for 1923-24. Pp. 4? 

 (Boulder, Colo.) 



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