226 'Journal of Coynparative Neurology and Psychology. 



onds. Immediately before the test tube was placed on the skin, the 

 signal word ''Now" was given and after the test tube had been 

 lifted, the subject reported Avhether or not he had felt anything and 

 also the quality of the stimulation. The usual procedure of request- 

 ing judgments when no stimulus or when an indifferent stimulus 

 was given was tried to see whether or not the subject guessed. After 

 some preliminary trials, the subject used exclusively the terms "hot," 

 "warm," "cool," "cold," "pressure," and "do not feel anything." 

 The subject also often voluntarily compared the temperature sensa- 

 tions of two or more stimuli in order and these reports gave a clue 

 to certain differences that will be reported later. Throughout the 

 test it was impossible to keep from the subject the knowledge that he 

 was being tested for temperature sensations, and whenever he reported 

 that the stimulus was accompanied by a sensation of pressure only, 

 he was asked to try to determine the character of the temperature. 

 At these times he was able to make a judgment only when a stimulus 

 was repeated, and after the test tube had been left on the skin from 

 10 to 60 seconds, until in all probability there had been time for 

 radiation of the heat or transmission of the stimulus to more nearly 

 normal parts. 



A series of early experiments on the hand showed certain devia- 

 tions from the results of Head and Sherren, and for this reason, 

 two areas were selected for careful examination, those which had 

 been previously used for the determination of the hair sensibility 

 on the upper part of the forearm near the bend of the elbow, and 

 on the lower part of the forearm near the wrist.^^ 



In the area near the bend of the elbow, each square centimeter 

 was tested separately, but in irregular order that no suggestion might 

 be given or olitained of the extent of the loss of temperature sensa- 

 tion, and each area was carefully gone over three times with each 

 form of stimulation. The resultant sensations that were reported 

 were, with two exceptions to be mentioned, the same in all three 

 tests, and the uniformity is a striking evidence of the accuracy of 

 the observations. In experiments in this area, no attempt was made 



"Figures 2 and 8. itp. 219 and 221. illnstrato tho areas which were carefully 

 tested. 



