HYDROCARBONS 



113 



FIG. 93. 



Charcoal burns with a very hot flame in a rapid current of air. A Blacksmith's Forge. 



On the right is an old bellows forge; on the left is an electric-power blower 



forge. Field Museum of Natural History, Chicago. 



FIG. 94. 



Model of a Blast Furnace. The one in cross section shows coarse iron ore, limestone. 



and coke (or coal) at the top; below this, the slag; at the bottom, molten iron. 



The blast of hot air enters through pipes near the bottom. 



Field Museum of Natural History. 



