200 



GENERAL SCIENCE 



FIG. 66. Cross-section of a blast or " reduction " furnace for the making of 

 pig iron. A, Outlet for molten iron; B, outlet for slag; C, C', inlets for hot air 

 blast; D, outlet which conducts escaping gaseous products to ovens for heat- 

 ing the " blast "; E, conveyor which feeds into the furnace coke, ore, and lime- 

 stone; F, floor to lower hopper which when filled automatically dumps itself; 

 G, counter-balance for floor of upper hopper. 



