Abstract
Poggendorff's Annalen der Physik und Chemie, No. 6.— The first paper, by G. Lundquist, On the reflection of light from the outside of isotropic bodies, is reprinted from the “Transactions” of the Royal Society of Upsala.— Dr. H. Brougersma contributes a memoir On the Medium in electrical influence, in which, following up the experiments of Riess, he examines Faraday's theory of electrical induction by polarisation of the medium, and describes in detail the apparatus with which he experimented, tabulates his results, and agrees with Riess's induction as to a direct influx of electricity.—The next article comprises a series of communications from the Mineralogical Institute of the University of Strasburg, in which Paul Groth treats of the crystalline form and thermo-electric properties of smaltine or arsenical cobalt. Its chemical formula is very variable, R = (Co, Ni, Fe) As2. Eight samples from different localities, which contribute a better knowledge of the hemihedral forms of the species, are discussed. He concludes that some of the forms hitherto regarded as holohedral are hemihedral forms with parallel sides. As with iron pyrites and cobalt-glance, with which it is isomorphous, one part of the crystal is negative towards copper, while the other half is positive.—Dr. Hintze treats of the chemical composition of leadhillite. Prof. Laspeyres two years ago described a mineral from Iglesias, in Sardinia, under the name of maxite, of which the formula was 5PbSO4 + 9PbCO3 + 4PbO + 5H2O. M. Bertrand, of Paris, soon after published an account of leadhillite from the same neighbourhood. The author proves that the two minerals are identical, and that the formula of leadhillite is not PbSO4 + 3PbCO3 as hitherto believed, but 2PbSO4 + 4PbCO3 + PbO + 2H2O. The next paper, by the same author, is crystallographic researches on the combination of aldehyde with the aromatic hydrocarbons. The chemical composition and crystalline forms are given of ditolyltrichloraethan, diphenyltribromaethan, diphenyltrichloraethylen, diphenyldibromaethan, dimonobromphenyltrichloraethan, &c. All these bodies belong to the monoclinic system.—Dr. A. Arzruni gives a short note on twin-growth in willemite. The next paper by the same author is “Optical researches on the turpentinoelhydrates,” which he follows by crystallographic and optical researches on compounds of urea. His last paper is on two isomorphous substances derived from benzol.—F. Zollner prints his important paper on the aggregation and position of the sun-spots, and concludes that they are cooled scoriaceous products.—Dr. Karl Braun contributes studies on the earth's magnetism.—Among the reprinted papers are Dr. Andrews' on ozone and Prof. Wright's on the polarisation of the zodiacal light.
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Scientific Serials . Nature 11, 119 (1874). https://doi.org/10.1038/011119a0
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DOI: https://doi.org/10.1038/011119a0