Abstract
LONDON Physical Society, Dec. 15. G. I. FINCH and A. G. QTJABBELL: Crystal-structure and orientation in zinc oxide films. A new type of electron-diffraction camera is described incorporating means for greatly increasing the accuracy hitherto obtainable in electron-diffraction analysis. Partially and completely oxidised zinc films have been examined by transmission. The normal type of zinc oxide is formed by the oxidation of zinc via a zinc oxide which is basally pseudomorphic with the zinc. The corrosion-resisting properties of zinc appear to be due, in the main, to a protective coating of such pseudomorphic zinc oxide. A. O. RANKINE: Note on the behaviour of the Eotvos gravity balance in fluctuating gravitational fields. Attention is directed to the semi-diurnal variation of gravity at a point on the earth's surface, due to lunar attraction and recently measured by Loomis. This temporal variation of g is much larger than the spatial differences measured by the Eotvos gravity balance, but it produces no effect on the balance. This constitutes an experimental proof of the power of the Eotvos instrument to discriminate between space and time changes of terrestrial gravitation. ALLAN FEBGTJSON and J. T. MILLEB: The temperature variation of the orthobaric density of unassociated liquids. A formula connecting the orthobaric density of a liquid and its temperature is developed in the form p = 2pc[A (1 m)° 3 + (1 tan)], where m is reduced temperature and A is a constant which varies slightly from liquid to liquid, and may be taken to have a mean value 0-911. The formula is a long-range one, and has been tested for thirty pure organic substances. It has been applied to the evaluation of expansion coefficients and to show the manner in which free and total molecular surface energy vary with temperature. L. C. MABTIN: The theory of the microscope (2). A discussion of the effects in dark-ground illumination when the image of the source of light is projected into the object plane by an illuminator of the symmetrical type. The treatment is two-dimensional. The conditions necessary for the formation of genuine and spurious images are investigated, and it is shown that the Abbe principle is theoretically valid in the cases considered. A short practical investigation with Grayson's rulings supports the theoretical conclusions, but indicates the desirability of closer examination of the causes of misleading interference phenomena. G. GBIME: Measurement of impact stresses in concrete. A quartz piezo-electric gauge, using a cathode-ray oscillograph for recording, has been developed to measure impact stresses in concrete. It is being employed to study the stresses in driven reinforced-concrete piles.
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Societies and Academies. Nature 133, 74–76 (1934). https://doi.org/10.1038/133074a0
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DOI: https://doi.org/10.1038/133074a0