286 



Dr. A. D. Waller 



[Feb. 4, 



we Lave to do with impulses conveyed, not along cerebrospinal, but 

 along sympathetic nerves. We may find time later to discuss the 

 question whether these are vasomotor or secretomotor or trophic 



nerves. 



Fig. 1. — This photogram is the simultaneous response of the 

 hand and of the foot of a normal subject, and is given as an 

 example to illustrate the method of investigation by double 

 response. In this example it is evident: (1) that the response 

 occurs sooner and is of snorter duration in the hand (palm) than 

 in the foot (sole). From the time record it can be seen that the 

 lost times in the hand and in the foot are respectively 2 and 

 4 seconds (approx.), and the durations of response 15 and 

 40 seconds (approx.). A closer approximation to true time values 

 would require a quicker record to be taken for the lost times and 

 a slower record for the durations. (2) That the response is 

 greater in the hand than in the foot. This magnitude is 

 measured by reference to the initial deflections made by passing 

 a current from T \y volt through each of the two circuits. In this 

 example the hand response is approximately JL, and the foot 

 response approximately -frr The rate of movement of the plate 

 is shown (not very distinctly) in half-seconds. The portion 

 shown in the figure occupied about 45 seconds. A similar 

 procedure by simultaneous double response is required for the 

 mapping out of the body-surface. Obviously the comparison 

 between right and left sides, upper and lower extremities, dis-tal 

 and proximal parts, flexor and extensor aspects, is to be carried 

 out with far greater expedition and certainty by double than it 

 could be by single records. 



6. Dreams are subjective phenomena occurring in the subconscious 

 state, with which we are all familiar during sleep, and during the 



