152 FIRESIDE SCIENCE. 



part of us where blood-vessels are to be formed, 

 every part where nervous influence is percepti- 

 ble, every organ, every tissue, muscle, and brain, 

 and nerve, and membrane, waste away like a 

 burning taper, consume to air and ashes, and pass 

 from the system rejected and useless ; and if we 

 did not repair the waste by supplying food, the 

 body would " burn up " as truly as if consumed by 

 a blazing pile. Starvation is a burning process ; 

 and those who perish from want of food may be 

 said to die from slow combustion. But we must 

 not be enticed away from the topic which it was our 

 purpose to consider. 



Clothing is composed of a variety of materials, 

 and these are used with reference to their influence 

 upon the body. Cotton and linen are cooler than 

 wool or silk, and consequently in this climate we 

 prefer the latter in winter and the former in sum- 

 mer. The former are bad conductors of heat, but 

 the animal products, the wool and the silk, are 

 much worse. Clothing serves the same purpose for 

 the body as coverings of wool or hair felting do for 

 steam or hot air pipes, namely, to keep in the heat, 

 or prevent loss by radiation. The worse conductor 

 any substance may be, the warmer it will prove as 

 clothing. Linen jackets and muslin dresses take 

 the place of cloth overcoats and thick shawls in 

 summer, because they are better heat conductors 



