Abstract
LONDON. Royal Society, Jan. 31.—S. Chapman: On the theory of the solar diurnal variation of the earth's magnetism. A ‘drift-current’ theory is proposed, which may account for the major part of the solar diurnal magnetic variation, but at present a decision cannot be made between this and the ‘dynamo’ theory; both theories require that the diurnal convective motion in the conducting layer differs largely in phase from that observed in the lower atmosphere.—G. M. B. Dobson, D. N. Harrison, and J. Lawrence: Measurements of the amount of ozone in the earth's atmosphere and its relation to other geophysical conditions. Daily observations of ozone in the upper atmosphere show that there is a well-marked area, with much ozone, immediately to the west of cyclones, while ozone is generally small in anti-cyclones. Polar air currents in upper atmosphere are generally associated with much ozone and equatorial currents with little. There is large annual variation in amount of ozone in high latitudes, but very little in low. In autumn the amount of ozone is nearly uniform over the hemisphere.—S. Chapman and J. M. Stagg: On the variability of the quiet-day diurnal magnetic variation at Eskdalemuir and Greenwich. Corresponding daily values of percentage departure of actual from the ‘normal’ range of diurnal solar magnetic variation (AR) for the same element at the observatories are closely correlated, whereas there is much less correlation between corresponding values of AR for different elements at the same observatory. Actual range (R) or AR sufficiently characterises daily variation at any season, because variation is the same, except in scale, on days of large as on days of small range.—L. H. Gray: The absorption of penetrating radiation. Adopting the hypothesis that penetrating radiation is a type of 7-radiation, its absorption in the atmosphere is investigated from the theoretical point of view.—R. d'E. Atkinson: The probability of excitation by electron impact. Starting from the quantum theory point of view, a method is developed of analysing the results obtained by the Townsend type of experiment, in which currents of the form i = ioe″x are found on varying the distance x between two parallel plates in a gas at comparatively high pressures.—N. W. McLachlan: Pressure distribution in a fluid due to the axial vibration of a rigid disc. Pressure distribution throughout the hemisphere on each side of a rigid disc, vibrating in a circular aperture in a plane wall of infinite extent, is considered. When wave-length is large compared with diameter of disc, pressure distribution is uniform over any hemispherical surface distant several diameters from disc. When wave-length is comparable with diameter, pressure decreases with increase in angular distance from axis. In general, the central zone is the only one of importance.—J. D. Cockcroft: Skin effect in rectangular conductors at high frequencies. At high frequencies the surface of the conductor becomes a stream-line in the magnetic field, and the problem of distribution of current becomes analogous to an electrostatic problem, surface current density corresponding to electrostatic surface density, whilst depth of penetration is the same as for infinite strips.—L. Rosenhead: Systems of line vortices in a channel of finite breadth. The investigations deal with a Karman street of vortices, or unsymmetrical double row, in a channel of finite breadth. A discussion on the symmetrical double row has also been incorporated.—T. P. Hilditch and N. L. Vidyarthi: (1) The products of partial hydro-genation of some higher monoethylenic esters. A method has been worked out of determining the constitution of the isomeric acids produced in hydro-genation of derivatives of the oleic series. Methyl esters of oleic, palmitoleic and erucic acids each yield a mixture of three position-isomerides, namely, the original acid, and the two acids in which an ethylenic linkage is in either of the positions adjacent to that originally occupied. The bearing of this upon the general theory of contact action at solid surfaces is considered; the opposite geometrical isomeride of original ethenoid acid, and also formation of position isomers, seem to be due to dehydrogenation of freshly formed saturated ester prior to desorption from catalyst.—(2) The products of partial hydrogenation of some higher polyethylenic esters. The various ethenoid bonds are not usually hydrogenated at same rate, and the isomerisation. phenomena discussed above are encountered. These complications are not sufficient seriously to interfere with the utility of the method as a means of determining constitution of polyethylenic derivatives.—P. K. Kichlu and D. P. Acharya: Infra-red radiations of active nitrogen. Photographic investigation of the spectrum from X75OO to A8900 shows that it is an extension of the first positive group of nitrogen in the green, yellow, and red regions. The most important group of lines of atomic nitrogen at about 8200 is absent.—T. H. Havelock: The vertical force on a cylinder in a uniform stream. The method of successive images, taking images alternately in surface of cylinder and in free surface of stream, is used. The method can be applied to any submerged body for which image systems are known.—R. C. J. Howland: Stress systems in an infinite strip.—A. H. Wilson: Perturbation theory in quantum mechanics. The convergence of the series of perturbations is discussed. Though the series is not in general convergent, yet it usually possesses an asymptotic character, and its use is therefore justified.—O. W. Richardson and K. Das: The spectrum of H2: the bands analogous to the orthohelium line spectrum.—O. W. Richardson and P. M. Davidson: The singlet bands of the hydrogen molecule (1). The strongest two band systems in the spectrum of H2 belong to 3 to 2 electron transitions analogous to those of the parhelium line spectrum. The properties of the final state are given with great accuracy.
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Societies and Academies. Nature 123, 229–230 (1929). https://doi.org/10.1038/123229a0
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DOI: https://doi.org/10.1038/123229a0