THE NEKVOUS SYSTEM 171 



the mantle of glory and achievement; but, com- 

 paratively speaking, I think that the physiologist 

 who investigates psychological phenomena has 

 more to offer us than the metaphysical speculator 

 who turns psychologist. 



In the early portion of the book we are intro- 

 duced to the physiological methods for determining 

 adrenaline, and are then shown that emotional 

 excitement gives rise to adrenaline in the blood in 

 amounts sufficient to be detected, though the 

 amounts may be less than a few parts per million. 

 One of the experiments dealing with emotional 

 excitement is to bring a dog and cat near one an- 

 other. The cat exposed to the barks of the dog 

 shows an increased adrenaline output. 



The fact that injection of adrenaline into the 

 body of an animal gives rise to a glycosuria, or an 

 increase of sugar in the urine (a form of what is 

 commonly called "diabetes"), and the fact that 

 emotional excitement induces an increased output 

 of adrenaline, leads directly to the next step : can 

 glycosuria be called forth by emotional excite- 

 ment? Cannon finds that it can. One experiment 

 is of exceptional interest. Of 25 members of the 

 Harvard University football squad whose urine 

 was examined immediately after a most exciting 

 contest during the season of 1913, 12 showed sugar. 

 After a day or two, after a complete rest, that is 

 the sugar disappeared completely. 



