TEMPERATURE GRADIENTS IN THE TISSUES IN MAN

Abstract

Temp, measurements in the tissues of the forearm and thigh were made either with steel-constantan thermocouples in needle form or by wire loops of manganin-constantan (wire of 80/j diam.). X-ray photographs were used to determine the position of the loop thermocouples. The errors introduced by the thermal conductivity of the couples are discussed, and an empirical correction formula is used. Confirmation was obtained of the presence of low muscle temp, in the limbs. The temp. gradients in the dermis were affected by the anatomical distribution of the blood vessels, so that the temp, recordable at 1.5-mm. depth was usually lower than at 1 mm., and reverse gradients exist. The low temp, at depths is explained as the result of heat interchange between contiguous arteries and veins. The effect of varying environmental conditions and sea bathing are considered. No correlation was observed between sensations of temp. and the temp, at any depth investigated.