Chemical progress on insulating oils

L. J. Berberich (1) prepared a review of progress in electrical insulation, as achieved by the combined efforts of physicists, chemists, and electrical engineers. Data are reviewed on: The relationship between power factor stability of oil-impregnated paper and the degree of refining received by the oil; an oxygen balance for oil aged in a closed vessel; the gas evolution from several oils subjected to electric discharge, as influenced by degree of refining; and the influence of adding aromatics on the gas evolution.