290 Dr. A. D. Waller [Feb. 4, 



people, when submitted to a standard stimulus at different times of 

 the day, gave responses of very different magnitudes ; the responses 

 were at their best about the middle hours of tlie day, when physio- 

 logical activity is high, as compared with what was elicited early in 

 the morning and late at night. And the conductivity of the 

 palm of the hand rose and fell during the day (as does the tempera- 

 ture). 



I thought it necessary to investigate this diurnal periodicity 

 rather closely to learn how much it might be necessary to take into 

 account the time of day when comparing results obtained on different 

 individuals. So I watched this periodicity on my own hands by 

 means of apparatus set up for the purpose in my dressing-room, so 

 that observations of conductivity could be taken at any convenient 

 time. The observations were recorded to form a graph on squared 

 paper ; and it may be remarked, by the way, that throughout the 

 observations the conductivity of my right hand has been found to be 

 higher than that of my left hand. 



11. The three weeks over which these observations extended 

 afforded me an admirable opportunity of observing the galvanometric 

 effects of my own normal variations of " temper." Most people are 

 more or less conscious of what may perhaps be called variations of 

 euphoria before breakfast, and of very distinct, if not outwardly 

 evident, variations of euphoria when the morning's letters are read. 

 In order to test this point a photographic recorder was set up in 

 connection with the galvanometer on my dressing-table, and I had 

 my letters brought up there and read to me and signalled on the 

 recording plate. Most of the letters made no impression upon me, 

 but I well remember one fortunate morning on which the post 

 included two distinctly effective letters which produced marked 

 effects duly recorded on the photographic plate. 



12. One is naturally tempted to ask what relation there may be 

 between the magnitude of the reaction and the mental quality. A 

 first step' towards an answer to this question has been taken by Miss 

 Waller, who has made systematic measurements of seventy-three 

 students of medicine, divided according to examination results into 

 an upper and a lower division. The average response was higher in 

 the former than in the latter — e.g. to disturbing questions the average 

 value of the rasponse came out about 50 iper cent, higher in the 

 upper division." 



13. I have often been asked whether pleasant and painful sensa- 

 tions produce similar or opposed galvanometric deflections. The 

 emotive response in its unmistakable form as a sharp movement 



* Mary D. Waller, " The Emotive Response of a Class of Seventy-three 

 Students of Medicine measured in Correlation with the Result of a Written 

 Examination," Lancet, April 6, 1918, 



