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altered, his comforts would have been abridged, 

 if, indeed, his existence had not been impossible. 



But even the vicissitudes of the seasons have 

 their charm, independently of their utility. There 

 is a pleasing variety in the succession of spring, 

 and summer, and autumn, and winter, exciting 

 and keeping alive the perceptions of enjoyment 

 in the beauties of nature, which a dull and uni- 

 form course, even of the finest weather, would 

 ultimately fail to produce. It is highly probable, 

 too, that the change of temperature continually 

 taking place, influences the currents of the at- 

 mosphere, and tends to accumulate and diffuse 

 the necessary moisture over every region. 



I must not omit to notice, in connection with 

 the subject of external heat, that the dark colour 

 of the skin of man, in the countries where this is 

 considerable, seems to be for the beneficent pur- 

 pose of tempering its effects on his constitution. 

 At first view it would appear that a dark skin 

 would rather increase than diminish these effects, 

 since dark colours absorb heat more readily than 

 light ones ; but we must remember that, though 

 the extreme of heat is sometimes greater, as I 

 have just observed, in these countries, than the 

 heat of the human body, the average heat is 

 generally considerably less, and dark colours, if 

 they absorb heat, so they also radiate heat bet- 

 ter than light ones ; more heat is thus, under 

 ordinary circumstances, given off from the body, 

 owing to the darkness of its complexion, than is 

 received into it. The average heat at Calcutta, 



