August i8, 192 i] 



NATURE 



799 



Societies and Academies. 



Paris. 

 Academy of Sciences, August i.— M. Georges 

 Lemoine in the chair. — The President announced the 

 death of M. Edmond Penrier. — A. Lacroix : The 

 mineralogical composition of rockallite. Dr. Char- 

 cot has recently made a successful landing on the 

 island of Rockall, examined its geological structure, 

 and collected specimens of the rocks. The present 

 paper contains an account of the mineralogical, 

 chemical, and spectroscopic examination of some of 

 these.— L. Maquenne and R. Cerighelli : The distribu- 

 tion of iron in plants. Figures are given of loo 

 determinations of iron in various organs of forty 

 species of plants. The quantities found are verv 

 small, varying from i to 362 parts of iron per million 

 of dry plant material. Young organs, buds, and 

 leaves contain more iron than the older ones. — A. de 

 Gramont and G. A. Hemsalech : The conditions of the 

 emission of the spark lines by the electric arc. Con- 

 ditions of experiment were devised so that the effects 

 of cooling the metallic vapours or the electrodes, 

 of heating the electrodes, and of varying the chemi- 

 cal nature of the medium in which the arc was 

 struck could be studied. The results prove that 

 spark lines are always emitted when the current of 

 the electric arc is obliged to pass through media 

 (vapours or gases) possessing a relatively low degree 

 of ionisation — that is to say, offering a strong re- 

 sistance to the passage of the current. This amounts 

 to saying that the emission of spark lines is related 

 to the existence of intense electric fields. — L. Antoine : 

 Perfect ensembles discontinuous throughout. — J. 

 Kampe de Feriet : Certain systems associated with 

 equations of finite differences or with partial linear 

 differential equations.— H. Beghin : The Anschiitz and 

 Sperry gyrostatic compasses.— M. Charcot: An ex- 

 pedition of the Poiirquoi-Pas to Rockall. An account 

 of the landing of two men on the island on June 19 

 and of three men on July i for the purpose of col- 

 lecting specimens of rocks and algas. — E. Dubois : 

 The minimum potential of electric discharge in 

 h\drogen at low pressures. A further study of the 

 variations produced in the discharge potential by the 

 occlusion of hydrogen by the platinum wire electrode. 

 — H. Peiabon : The resistivity of selenium. The re- 

 sistance of liquid selenium falls rapidly as the tem- 

 perature rises, the logarithm of the resistance being 

 a linear function of the temperature. While the re- 

 sistance of liquid selenium is defined by the tem- 

 perature, this is not the case with the solid grey 

 selenium, the resistance of which depends upon Its 

 previous heat treatment. — M. Sauvageot : The re- 

 tarded solution and premature precipitation of 

 cementite in eutectic and h\'pereutectic carbon steels. 

 — A. Damiens : The system bromine-tell^irium. The 

 nature of the lower bromide of fellurium. Since 

 bromine has no solvent action on TeBr,, the thermal 

 study is reduced to that of the system TeBr4-Te. 

 No indication of the compound TeBr, was obtained 

 from the metallographic or thermal analysis, but 

 this substance was proved to be present by heating 

 in a yacuum. This gave a non-volatile portion and 

 two sublimates differing in colour and volatility. 

 One of these was TeBr, and the other a mixture 

 of tellurium and its tetrabromide in the proportions 

 required to form TeBr,. Hence the lower bromide 

 would appear to exist in the gaseous state, but is 

 unstable in the solid state, decomposing into tellurium 

 and the tetrabromide on solidification. — P. Woog : 

 The oiliness of fatty bodies. The property of oiliness 

 or greasiness, valuable in lubricants, is not capable 



NO. 2703, VOL. 107] 



of exact definition. The molecular volumes of a 

 considerable number of lubricating oils, fatty and 

 mineral, have been determined by endoscopic or boil- 

 ing-point methods, and it is shown that in general 

 the oiliness or greasiness of an oil diminishes as the 

 molecular volume decreases. — V. Auger : The equili- 

 bria of tri-, tetra-, and pen'ta-valent vanadium in con- 

 centrated sulphuric acid solution. — C. D. Zenghelis : 

 The detection of nitrogen in organic compounds. 

 The compound is heated with a reagent consisting 

 of soda-lime (two parts) and copper powder (one 

 part), and the ammonia evolved detected by the 

 formaldehyde-silver nitrate reagent previously de- 

 scribed by the author. Tests with a large number of 

 different types of nitrogen compounds are given, the 

 limits of delicacy ranging between 005 and 0001 

 milligram of nitrogen. — E. Rengade and J. Clostre : 

 The estimation of water in transformer oils. The oil 

 is heated to 80° C. in a current of dry air, and the 

 escaping vapours are cooled with solid carbon dioxide 

 or liquid air. — E. E. Blaise : The preparation of the 

 acyclic 8-diketones. Glutaric diethylamide is con- 

 densed with an alkyl magnesium bromide. The re- 

 action does not proceed normally, much gas being 

 evolved, but the 8-diketone is formed, with a yield of 

 25 to 30 per cent. Dipropionylpropane and dibutyryl- 

 propane have been prepared by this method : their pro- 

 perties and reactions are described. — H. Gault and R. 

 Weick : Additional properties of the keto-enolic double 

 linkage. A study of the reactions of one of the three 

 isomeric phenylpyruvic esters with ammonia and 

 diethylamine.— R. Fosse and G. Laude : Svntheses 

 of cyanic acid and urea by the oxidation of organic 

 substances : amides, nitriles, and methylcarbylamine. 

 — M. Samec and Mile. Anka Mayer : The synthesis of 

 amylopectin by the phosphoric etherification of the 

 ervthroamyloses. — J. Savornin : The middle atlas of 

 Morocco. — Ph. Wehrle : The notion of period in the 

 study of the nuclei of pressure variations. — A. Car- 

 pentier : The presence of Cycadophvtes in the 

 Wealdian layer of Feron. — L. Blaringhem : Re- 

 searches on the hybrids of flax (Linutn usitatissi- 

 mum). — A. Guilliermond : Cytological observations on 

 the bud of Elodea canadensis.- — G. Bertrand and 

 Mme. M. Rosenblatt : The general presence of man- 

 ganese In the vegetable kingdom. According to 

 Maumene, certain plants are free from manganese. 

 The authors' analyses show that none of the ex- 

 ceptional cases cited by Maumene can be retained : 

 manganese is present in all plants without excep- 

 tion.— S. Metalnikow and H. Gaschen : Immunity and 

 hypersensibility in the caterpillar. — R. Sazerac and 

 C. Levaditi : The treatment of syphilis by bismuth. 

 A detailed account of the treatment and results in five 

 cases. 



SVDNFY. 



Linnean Society of New South Wales, June 29. Mr. 



G. A. Waterhouse, president. In the chair. — G. F. 

 Hill : Notes on some Diptera found in association 

 with Termites. In opening up galleries of Masto- 

 termes darwiniensis and Calotermes irregularis, the 

 author frequently found larvae and pupae of Try- 

 paneidae and Syrphidae ; he describes one species 

 belonging to each family, that in the Syrphidae being 

 new. — Vera Irwin-Smith': Studies in life -histories of 

 Australian Diptera Brachycera. Part i. : Stratio- 

 myiidae. No. 2 : Further experiments in the rearing 

 of Metoponia rtibriceps. Attempts to rear the lar\'al 

 M. riibriceps from the egg have met with considerable 

 success, and it has been found possible to breed from 

 flies reared from the larva in captivity. The cycle, 

 from larva to larva of the next generation, has been 

 obtained, but the bred larvae all perished at an early 



