Abstract
Wiedmann's Annalen der Physik und Chemie, No II.—On the speed of electrolytic ions, by F. Kohlrausch. This is a compilation of tables of absolute velocities, of mobilities, and of coefficients of electrolytic friction according to the latest and most reliable data.—Contributions to the knowledge of the absorption and branching of electric oscillations in wires, by Ignaz Klemencic.—The resistance which causes evolution of heat during the passage of very rapid oscillations depends upon the magnetic permeability of the wire, but in a different manner from that in the case of a constant current. The amounts of heat developed in wires of iron, German silver, brass, and copper 6cm. long and of 0˙018 cm. radius, were in the proportion of 10˙5: 1˙75: 1: 1, the last being probably a little too large. The branching of the oscillations is only affected by the self-induction of the wires, not by their resistance.—The emission of hot gases, by F. Paschen (see p. 82).—A simple method of testing the conductivity of dielectric liquids, by K. R. Koch. The apparatus used for this method is a modified Dewar capillary electrometer, in which a drop of the substance to be examined takes the place of the drop of sulphuric acid usually employed for determining differences of potential. Any electrolytic polarisation is indicated by a movement of the drop of liquid, which should not be more than 0˙5 mm. long. The conductivity of various dielectrics has thus been studied, and has in many cases been found to be due to impurities. Benzol, carefully-cleaned and freed from moisture, ceased to show any polarisation.—On the magnetic susceptibility of oxygen, by R. Hennig (see Notes).
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Scientific Serials. Nature 49, 117–118 (1893). https://doi.org/10.1038/049117b0
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DOI: https://doi.org/10.1038/049117b0