374 PHYSIOLOGY AND HEALTH. 



became insane, therefore, in circumstances which were 

 harmless to their associates. 



867, The immediate sympathy between the other organs 

 and the brain compels it to feel their ills, and to be often- 

 times deranged with them. Pains of the head and confusion 

 of mind are connected with the sickness of the stomach. 

 Insanity sometimes rises from dyspepsia. In such cases, 

 even during convalescence, the mental disorder is brought 

 back by renewal of the digestive trouble. Any error in 

 diet, any improper food, too hearty meals, or gas in the 

 stomach, excites the brain ; then the old delusions again 

 return, and the mind suffers acute distress until the stom- 

 ach is relieved. 



868. The suppression of evacuations to which the sys- 

 tem has become accustomed sometimes disturbs the brain, 

 and causes mental derangement. Even the closing an 

 ulcer which has been .running for a long time may produce 

 the same effect. 



86.9.' Very great cold confuses the brain, and deranges 

 the mind. Captain Parry, in the journal of his voyage to 

 the Northern Ocean, states, that, when his men were exposed 

 to extreme cold, they seemed to have lost their power of 

 mind, and upon one occasion, when some of his men re- 

 turned from an expedition in which they had suffered from 

 great severity of weather, they were confused, and stared 

 vacantly and wildly. They could give no account of them- 

 selves, nor of their late conduct; but, after they recovered 

 their natural temperature, they regained their clearness of 

 intellect. Similar instances are given in Fremont's journal 

 of his second expedition over the Rocky Mountains. A 

 high, as well as a low temperature, usually affects the mind 

 unfavorably. Mania is sometimes caused by exposure of 

 the head to great heat. 



870. Very frequent causes of insanity are connected with 

 the abuses of the mental and moral powers. As dyspepsia 

 arises from errors in diet, from the wrong purposes to which 

 the digestive organs are applied, or from the excessive bur- 



