ON NERVOUS ENERGY 68 



that occupation is " easy " because it looks simple and 

 appears to call for no great muscular effort. But such 

 work generally has to be executed very rapidly, and 

 consequently necessitates a great expenditure of nervous 

 energy. The result is that the factory worker, though 

 employed at work which is called " easy," often suffers 

 from nervous exhaustion at the end of the day's work, 

 especially in hot weather. 



The effects of nervous exhaustion are peculiar : " There 

 occurs during an exercise of speed a nervous commotion 

 resembling that which follows a strong emotion or a 

 powerful mental strain. These results are especially 

 marked in impressionable persons, and it is among them 

 that we may see how fatigue caused by speed is adverse 

 to the repair of the system. Many children, after running 

 about too much, can neither eat nor sleep. Many horses 

 which are too nervous refuse their oats after a hard 

 day's hunting. We do not see this capricious appetite 

 in coarsely built animals doing collar work all day." * 



The symptoms above described are common among 

 factory workers, especially during the hot months. It 

 is also true that the more highly strung types are the 

 more easily and the more often affected. When we 

 reflect that boys and girls in their teens, the chief period 

 of development, are worked all day at occupations which, 

 although " easy," require a large and incessant expendi- 

 ture of nervous energy, and that the result is often the 

 loss of appetite and sleep, there is nothing strange in 

 the fact that it often produces a marked deterioration 

 in the physique. 



The reason why the symptoms described above are 

 more common in hot weather is because heat, and 

 especially moist heat, has an exhausting effect on the 



1 Physiology of Bodily Exercise, Fernand Lagrange, part iv, ohap. iv. 



