Temp. gradients existing in the air vertical to the surface of the extensor aspect of the left forearm were determined by use of constantan-manganin thermocouples of the loop pattern. The arm was bared 1 or more hrs. prior to observation, during which it was immobilized. The temp, gradients are of uniform type; the slope varies with the dry bulb temp. and the amount of air movement. With high dry bulb temp. and little air movement the temp. of the air 5-6 mm. from the shaved or unshaved surface is 1.0[degree]C. below that of the surface. With lower dry bulb temp. and increased air movement the gradients become steeper. However, under extreme conditions the temp. at 0.5 mm. distance has not been more than 1.0[degree] below that of the surface. The protection afforded by the hairs is demonstrated.