The electrical conductivity of thin oil films. Part I.-General nature of the phenomenon

Abstract

It has long been a common practice to cover accumulator terminals with vaseline; Price and others at a discussion at the Physical Society mentioned that potentiometer contacts were improved by immersion in kerosine oil; Manley found that the resistance of the plugs in a resistance box was invariably more constant and very nearly always lower when they were lubricated with vaseline than when they were dry; Kraus, and Melsom and Booth in investigations upon contact resistances, such as switches for electrical machinery, obtained similar results. Vaseline and heavy paraffin oil are now widely used for application to plugs and sliding contacts on measuring instruments. In view of the fact that these substances are ordinarily regarded as excellent insulators, their use for the above purpose appears somewhat anomalous, and the object of the present investigation is a detailed examination of the region in which a transition from insulation to conduction appears to take place.