146 



EXPERIMENTAL PHARMACOLOGY 



duction coil as shown in Fig. 137. The subject holds the 

 telephone to his ear and listens (with closed eyes) for 

 the click of the closing of key B by the operator. At the 

 instant the sound is heard the subject opens key A. The 



KeyB 



Fig. 137. Arrangement of apparatus for recording reaction time for hearing. 



reaction time for sound is thus recorded on the drum. Re- 

 peat this twenty or thirty times and estimate from the 

 tuning fork record the average length of time required for 

 the reaction. 



The subject now takes some whiskey or brandy (or wine) 

 as indicated above (1) and after fifteen minutes his reac- 



