346 THE CHEMISTRY OF CREATION. 



heat in consequence of the large proportion of 

 carbon and hydrogen entering into their com- 

 position. The appetite in a healthy man is 

 the beautifully-adjusted measure by which the 

 fuel-food requisite for the condition in which 

 he is placed is determined. In the keen air 

 of the north, it is much more loud in its calls 

 than in the heated and depressing atmosphere 

 of the Equator ; and a careful attention to this 

 natural index would enable men in these con- 

 trasted situations to regulate their supply of 

 food accordingly ; and would doubtless tend 

 in some degree to the preservation of health 

 of the body under these opposite circumstances. 

 It has been remarked, that over-warm clothing 

 and a keen appetite in temperate weather are 

 incompatible with each other; and doubtless 

 this curious fact is connected directly with 

 respiration. When the body is covered with 

 a number of non-conducting materials, its loss 

 of heat is greatly lessened, and the call upon 

 respiration is therefore lessened in proportion : 

 and this again tells back upon the appetite, and 

 informs the system, so to speak, that less food 

 is necessary for its wants. But reverse the 

 condition; let a man be clad in rags, and the 

 intensity of his appetite increases proportion- 



case the individual must inhale eight times as much oxygen 

 as an ordinary adult, and his pulse must move at the rate of 

 500 beats a minute which is clearly impossible. 



