WATER 89 



these circumstances the circulation of winds, 

 bearing away water vapor from the tropical 

 oceans, is inevitable, and the process is 

 intensified by the high specific heat of 

 water. 



The living organism itself is directly favored 

 by this same property of its principal constit- 

 uent, because a given quantity of heat pro- 

 duces as little change as possible in the tem- 

 perature of its body. Man is an excellent 

 case in point. An adult weighing 75 kilo- 

 grams (165 pounds) when at rest produces 

 daily about 2400 great calories, which is an 

 amount of heat actually sufficient to raise 

 the temperature of his body more than 32° 

 centigrade. But if the heat capacity of his 

 body corresponded to that of most substances, 

 the same quantity of heat w T ould be sufficient 

 to raise his temperature between 100° and 

 150°. In these conditions the elimination of 

 heat would become a matter of far greater 

 difficulty, and the accurate regulation of the 

 temperature of the interior portion of his body, 

 especially during periods of great muscular 

 activity, well-nigh impossible. Extreme con- 

 stancy of the body temperature is, of course, 

 a matter of vital importance, at least for all 

 highly organized beings, and il is hardly 

 conceivable that it should be otherwise. In 



