CANDLE SMOKE. 83 



Q. Why do not " Argand burners" smoke ? 



A. Because a current of air passes 

 through the middle of the name; and 

 therefore the carbon of the interior is 

 consumed, as well as that in the outer 

 coating of the flame. 



Q. Why does a LAMP-GLASS DIMINISH the 

 SMOKE of a lamp? 



A. Because it both concentrates and 

 reflects the heat of the flame ; in con- 

 sequence of which, the heat is so greatly 

 increased, that very little carbon escapes 

 unconsumed. 



CHAPTER VI. 

 ANIMAL HEAT. 



Q. What is the cause of ANIMAL HEAT? 



A. Animal heat is produced by the 

 combustion of hydrogen and carbon in 

 the capillary veins. 



