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Academy of Sciences, Sept. 7.—M. Fremy in the chair.— M. Resal presented the Academy with the second volume of his “Traite de Mecanique Generate,“and made some remarks thereon.—M. P. Volpicelli addressed a letter to the president, stating that in 1854 Melloni had communicated a note to the Academy, entitled "Researches on Electrostatic Induction.” Fifteen days afterwards the Italian physicist died of cholera at Naples, and since that time the author (M. Volpicelli) had submitted fifteen communications to the Academy on the same subject, all of which confirmed Melloni's theory of electrostatic induction. M. Volpicelli now begs the Academy to appoint a commission to report on these experiments, and expresses a hope of being permitted to repeat them before it. MM. Becquerel, Faye, Fremy, Edm. Becquerel, and Jamin were named commissioners.-Sixth note on the electric conductivity of ligneous bodies, by M. Th. du Moncel.-Presence of zircosyenite in the Canary Isles, by M. Stan. Meunier. The mineral was found in a collection made by M. Webb on the Pena Mountains.-On some laboratory experiments concerning the action of toxic gases on Phylloxera; actual state of the malady in the Charente provinces; extract from a letter from M. Maurice Girard to M. Dumas. The gas tried was that liberated from a sulpho-carbonate. Pieces of brick saturated with the solution of the salt were placed in the bottoms of flasks; above the solution and saturated brick some strong paper was supported on which were placed phylloxerised roots. The roots thus escaped direct contact with the solution and received only the gases evolved (CS2 and H.JS). At the end of twenty-four hours nearly all ir.e i ise ts were dead, with the exception of some small larvae and some eggs; at the end of two days all the insects and the greater part of the eggs were dead; while at the end of four days complete death of the eggs took place. During the experiment the flasks were kept in the dark, and some control flasks containing phylloxerised roots only placed with the others: nearly all the insects and eggs survived in these last flasks.-On some new points in the natural history of Phylloxera vaslalrix; a letter irom M. Lichtenstein to M. Dumas. The author thus sums up the life history of the insect so far as at present known:-(1) Colonising females appearing probably in August and September; (2) small uniform progeny hybernating; (3) Oval, pyriform, testudiniform types, reproducing by parthenogenesis all the summer; (4) Pupse of twTo forms, oval and narrow at the waist, specially found on the nodosities of the rootlets in June and July; (5) Swarming takes place in August: the insects emerge from the earth in myriads exactly as in a formicary when the winged insects escape; (6) Laying of eggs on the leaves of Quercus cocci/era, end of August; (7) Birth of sexual apterous individuals. Copulation and production of colonising females.- On some processses for destroying O'idiuvi and Phylloxera; extract from a letter from M. Desforges to M. Dumas.-Employment of the lime from gas purifiers to check Phylloxera; extract from a letter from M. L. Petit to M. Dumas.-Observation of an extraordinary passage of corpuscles across the sun; a telegram from M. Gruey, of the Toulouse Observatory, to the president. The passage took place on the 5th, 6th, and 7th of the present month.-On some applications of Abel's theorem relating to elliptic functions to curves of the second degree, by M. H. Leaute.-Note on magnetism, by M. F. M. Gaugain; a continuation of former researches.-Note on the nature of the sulphurising compound mineralising the thermal waters of the Pyrenees, by?. E. Filhol.-Note on chlorophyll, by?. E. Filhol. The chlorophyll of monocotyledons (Graminse, Cypera-cese, Liliaceae, & c.) treated with a small quantity of hydrochloric acid becomes turbid, and the solution, on filtration, leaves a black crystalline compound on the filter. This substance has been examined in some detail. It is remarkable that a solution of chlorophyll from dicotyledons yields, under the same treatment, a dark compound which is amorphous. - On some phenomena of localisation of mineral and organic substances in Mollusca, Gasteropoda, and Cephalopoda, by M. E. Heckel. Specimens of Helix aspersa and Zoniies algirus were fed with white lead, or with acetate of lead mixed with wheat flour. An accumulation of metal was found in the liver and also in the cerebral ganglia. loligo vulgaris, Sepia officinalis, and Octopus vulgaris were fed during two months with garancine (mixed with meat). In no case was the internal shell coloured, but the cephalic cartilage and all the cartilaginous portions of the skeleton of these Mollusca were coloured after an experiment of three months' duration. The author points out the necessity of distinguishing clearly the""hard parts belonging to the skeleton from those belonging to the shell.-On the storm of the night of 1st to the 2nd of Sept. 1874, observed at Versailles; a note by M. Ad. Berigny. 17 59 mra.[of rain fell during the storm, and the lightning struck four points in Versailles.
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Societies and Academies . Nature 10, 414 (1874). https://doi.org/10.1038/010414b0
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DOI: https://doi.org/10.1038/010414b0