246 THE HOUSE I LIVE IN. 



skins has some effect in keeping us cool ; but 

 this cannot be the sole cause why men can 

 remain with impunity in places heated to a 

 greater temperature than boiling heat. There 

 must be other causes not yet fully understood. 

 As to the reason why we retain so high a 

 heat as 98, when the temperature of the at- 

 mosphere is almost always greatly below that, 

 there have been a great many speculations 

 guesses by philosophers; but they have, in 

 general, been mere guesses. The process of 

 digestion, the formation of chyle, the change 

 of chyle into blood, and the change of the 

 blood in the lungs especially the latter are 

 all believed to have a part in the work. Yet 

 they do not, by their united efforts, accomplish 

 one half of it ; and it remains for future anato- 

 mists and physiologists to investigate the sub- 

 ject more deeply. How far the laws of the 

 great Creator may ultimately be discovered, in 

 this, as well as in a thousand other things, of 

 which we are yet ignorant, it is not easy for 

 us, in the present infancy of human knowledge, 

 to conjecture. 



