“…Adaptation of receptors to cold takes place in time of the order of seconds or fractions of seconds (Hensel, 1952), but the low conductivity of the tissues of the hand and the existence of a blood supply to the skin make it likely that in an intact limb immediate adaptation would require time of the order of 10 sec or of 1 min (Wolf & Hardy, 1941;Hensel, 1952). Experimental demonstration of habituation in man usually requires time of the order of 1 day (Davis, 1934;Glaser & Whittow, 1954), but it was of interest to find out whether adaptation might be acquired and retained over shorter periods. It was decided, therefore, to conduct tests at intervals of one minute, one hour, and one day.…”