The application of the thermocouple has provided a new and exact technic for the determination of skin temperatures. The fineness of the instrument, however, has to a certain extent created a false impression as to the accuracy of the determinations. The inherent variability of the phenomena governing the level of the surface temperature has undergone little investigation, and its effect on the reliability of single determinations has been largely unchecked. In the present investigation an attempt was made to determine the magnitude of the variation to be expected in such a study.
The investigation was conducted in a windowless, brick-lined, circular room, the temperature of which was maintained between 23 and 24 C. and the air flow of which was so regulated as to be imperceptible to the nude subject. The relative humidity was measured at frequent intervals by a sling psychrometer. The subjects were male schizophrenic patients with