BODY HEAT 67 



little doubt that, in spite of the regulating mechanism, 

 the body becomes habituated to a certain level or balance 

 of heat production and loss, and takes a little time to 

 readjust matters when external conditions suddenly 

 change. Captain Parry, the Arctic explorer, tells us, for 

 instance, that when he and his men had been exposed to 

 a temperature of 13 F. for some time, they complained 

 of the heat when the thermometer rose to 26 F., and 

 everyone knows how much more trying a cold day is in 

 the middle of summer than a day of the same tempera- 

 ture in mid-winter, even although the clothing be the same. 



Similarly, persons who inhabit warm latitudes become 

 accustomed to losing much heat from the surface by 

 evaporation, and are out of practice, as it were, in pro- 

 ducing more heat to meet emergencies, and are therefore 

 prone to succumb to chills when they remove to colder 

 regions. 



Alcohol in excessive doses and prolonged anaesthesia 

 both paralyze the heat-regulating mechanism. A man 

 who is ' dead drunk ' resembles a cold-blooded animal ; 

 exposure to cold produces not an increase but a decrease 

 in combustion, and his temperature steadily falls 

 (Pembrey). It is not surprising, therefore, that ' death 

 from exposure ' chiefly occurs in the case of intoxicated 

 persons. 



An anaesthetized patient also cannot regulate his 

 temperature, and the importance of warm surroundings 

 in promoting recovery from prolonged operations and in 

 obviating * shock ' is generally recognized. 



' Heat stroke ' and ' heat exhaustion ' are probably 

 also due to a disturbance of the mechanism for regulating 



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