Abstract
LONDON. Chemical Society, June 20.—Dr. W. J. Russell, F.R.S., President, in the chair.—The following papers were read:— Observations on the melting-point of some salicylic and anisic compounds, by Dr. W. H. Perkin, F.R.S. The author, in 1867, described methylated and ethylated salicylaldehydes as colourless liquids which do not solidify when cooled in a freezing mixture, whereas Voswinckel states that methylated salicylalde-hyde is a solid melting at 35° (Ber. der deut. chem Gesellsch., 1882, 2024). Further experiments show that although the methylated aldehyde does not readily crystallize in a freezing mixture it can be made to do so, but the crystals so obtained melt at 2°7-3°. Prismatic crystals having the melting-point described by Voswinckel were once obtained on evaporating an ethereal solution of the aldehyde, and it is found that if the oily aldehyde is touched with one of these it immediately becomes a solid mass, having a melting-point of 35° when these crystals are fused, and the resulting oil cooled in a freezing mixture, crystals melting at 2°7-3° are again formed. It is therefore established that methylated salicylaldehyde forms crystals of two kinds, having melting-points differing by about 32°.—The action of propionyl and butyryl chloride on phenol, by the same. When phenol is acted upon by propionyl chloride, a secondary product, propionyl phenol, C3H5O. C6H4. OH, is formed in addition to phenyl propionate. A corresponding reaction occurs when phenol is treated with butyryl chloride.— The nature of solutions as elucidated by a study of their freezing temperatures, by Mr. S. U. Pickering. By determining the freezing temperatures of mixtures of sulphuric acid and water, the author has obtained results which in his opinion confirm the existence in solution of the majority of the hydrates of sulphuric acid which have been indicated by a study of the densities, heat of dissolution, heat capacity, and electric conductivity of these solutions (cf. p. 166).—Note on the determination of the molecular weight of substances in solution, especially colloids, by Prof. H. E. Armstrong.—The correspondence between the magnetic rotation and the refraction and dispersion of light by compounds containing nitrogen, by Dr. J. H. Gladstone, F.R. S., and Dr. W. H. Perkin, F.R.S.—Note on the oxidation of para-diamines, by Prof. R. Meldola, F.R.S., and Mr. R. E. Evans. The authors find that the amido-groups of paraphenylenediamine are split off in the form of ammonia, when it is oxidized to quinone by the action of potassium bichromate.—Monobenzylderivatives of the phenylenediamines, by Prof. R. Meldola and Mr. J. H. Coste. Monobenzyl meta- and para-phenylenediamines have been prepared, and their oxidation products examined. The paradiamine, when oxidized with an equi-molecular proportion of benzylaniline,yields an unstable greenish-blue indamine, and when oxidized with two molecular proportions of benzylaniline at the temperature of boiling water, forms an azine or benzylated saffranine which is of interest as being produced, in contradiction to the generally received view, from one molecule of a diamine, and two molecules of a secondary instead of a primary monamine.—Note on a yellow pigment in butterflies, by Mr. F. G. Hopkins. The colour effects on the wings of lepidopterous insects are for the most part probably due to purely physical causes, but in some cases pigments are undoubtedly present. A yellow pigment, which is found in its purest form in the common English brimstone butterfly, and may also be detected in the wings of a very large number of day-flying Lepidoptera, can be obtained from the wings by simple treatment with hot water, in which it is freely soluble, and may be identified by its yielding a marked murexide reaction, when evaporated with nitric acid, and afterwards treated with ammonia or potash. The common brimstone butterfly yields somewhat less than a milligram of pigment from each insect; larger foreign species, such as those belonging to the species Callidryas, may yield as much as 4-5 milligrams. Examination of the pigment reveals its near relationship to mycomelic acid, a yellow derivative of uric acid; and the author suggests that it may possibly be a condensation product of uric and mycomelic acids.—Zinc dextrosate, by Mr. A. C. Chapman.—βbromonaphthalenesulphonic acids, by Mr. R. W. Sindall. It is found that dichloronaphthalenes are chiefly formed when the chlorides of the β-bromonaphthalenesulphonic acids are distilled with phosphorus pentachloride, the brouane atom becoming displaced by chlorine.—Isomeric change in the naphthalene series, No. 5; β-iodonaphthalenesulphonic acids, by Prof. Armstrong and Mr. W. P. Wynne. A further contribution to the study of isomeric change in the naphthalene series, in which additional evidence, derived from the investigation of the acidsobtained on sulphonating β iodonaphthalene under varied conditions th, is adduced in favour of the viewat the β-derivatives of naphthalene are formed by isomeric change from α-derivatives and not by direct substitution.—The formation of sulphones on sulphonating naphthalene-derivatives by means of chlorosul-phonic acid, by Mr. W. M. Heller.—Note on the hydration of cyanides, by Prof. Armstrong. Unlike the α-derivative, β-cyanonaphthalene cannot be sulphonated; if, however, it is dissolved in fuming sulphuric acid, and the solution poured into water, it is completely converted into the amide of naphthoic acid. In like manner trichloracetonitril, CC13. CN, slowly combines with sulphuric anhydride, forming a crystalline compound which en treatment with water undergoes immediate and complete conversion into trichloracetamide. These cases appear to afford striking evidence in favour of the view that hydrating and hydrolytic agents act by forming compounds directly attackable by water; they serve, in fact, to support the integration rather than the dissociation hypothesis of chemical change.— The existence of salicylic acid in certain genera of the Liliacea, by Dr. A. B. Griffiths. The author states that he has isolated salicylic acid from the leaves, stems, &c, of Tulipa, Yucca, and Hyacinthus.—On the oxidation products of acenaphthene, by Mr. T. Ewan and Dr. J. B. Cohen. — Schiitzenberger's process for the estimation of the oxygen dissolved in water, by Sir H. E. Roscoe, F.R.S., and Mr. J. Lunt.—Isomeric change in the phenol series (third notice), by Mr. A. R. Ling.
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Societies and Academies. Nature 40, 335–336 (1889). https://doi.org/10.1038/040335a0
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DOI: https://doi.org/10.1038/040335a0
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