Abstract
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Physical Society, November 3. MABY D. WALLER: Vibrating properties of metals at different temperatures. Since the damping of the vibrations is mainly due to internal friction or solid viscosity, it is greatly altered either by previous heat or mechanical treatment and by impurities. On account of the large variations of the vibrating properties with temperature, it will be possible to obtain, by observation of irregularities in these variations, much interesting information regarding the state of metals and alloys at different temperatures. MABY D. WALLER: Production of sounds from heated metals by contact with ice and other substances. The conditions are described under which soft notes may be produced from heated metal bars brought into contact with ice and a number of other substances. These substances must either sublime or boil or decompose with the evolution of gas, at temperatures for which the metal to be excited still retains adequate vibrating properties. P. C. MAHANTI: The band spectrum of barium oxide. New measurements of the bands of barium oxide have been made from moderate-dispersion and high-dispersion spectrograms. The band-head data of the early investigations have been extended in the red region as far as X 8000. The bands lying between X 8000 and X 4300 have been assigned to a single system. F. W. G. WHITE: Diurnal variation of the intensity of wireless waves reflected from the ionosphere. An account is given of the diurnal variation of the relative intensity of waves returned from the ionised regions of the upper atmosphere as observed over the early morning period from about 2 a.m. until about 9 a.m. The relative intensity is taken as the ratio of the intensity of the downcoming wave to that of the ground wave. The influence on the intensity of electron-limitation and of absorption limitation is discussed, in the light of theoretical ionisation curves given by Chapman. The experimental observations described show that the magneto-ionic doubling of the echo, which has been observed by Appleton and Builder for the F region, occurs also for the E region. J. A. RATCLIFFE and E. L. C. WHITE: Automatic records of wireless waves reflected from the ionosphere. The records extend over a period of fourteen months. They indicate that the region below the F region may be triply stratified and consist of the intermediate region (effective height approximately 120-180 km.), the E region (effective height approximately 100-120 km.), and the e region with an effective height which is always nearly 105 km., within ± 5 km. The e region is intermittent in its occurrence, and is identified with the ‘nocturnal E region’ mentioned in previous papers. The temporal variations of the ionisation in these three regions is discussed.
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Societies and Academies. Nature 132, 943–944 (1933). https://doi.org/10.1038/132943a0
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DOI: https://doi.org/10.1038/132943a0