Abstract
Investigations were carried out by Tucker's Audiometer, in which a pure note, electrically produced, is reduced by means of resistances until it ceases to be heard. Thirty cases of middle-ear deafness with paracusis were investigated. In two there was absolute paracusis, the sound being better heard with disturbing noise. In sixteen (relative paracusis) there was little diminution in hearing power in the presence of a disturbing sound. In twelve the hearing was apparently improved in the presence of a disturbing sound in the opposite ear (crossed paracusis). We have found no previous description of this last condition, and venture no suggestions as to its significance.