REACTIONS IN BLAST FURNACES. 739 



The above figures may be conveniently combined as follows: 



Volatile portion. 



Carbou from fuel 26. 533 



Gases from fuel 0.985 



Carbonic acid from ore, dolomite, and ash 10. 691 



Oxygen from Fe 2 Oa in ore and hematite, escaping as CO 3 3.208 



Oxygen from MuO in ore and hematite, escaping as COj 0. 747 



Oxygen from PbO escaping as C0 3 1.640 



Moisture from whole charge 7.341 



f Pb=1.040 

 Dust and fumes carried away ^ Ag=0.011 



i. Dust=0. 890 



1.941 



Total 53.086 



Slag. 



Silica 26.202 



Alkalies 1.051 



Magnesia 5. 239 



Lime 5.894 



Alumina 4.031 



Protoxide of iron 28.873 



Pevoxide of iron 0.865 



Protoxide of manganese 3.318 



Protoxide of lead 1.860 



Old slag 17.441 



Total 94.774 



Less dust.. 0.890 



Total slag produced 93.884 



Bullion. 



Lead 20.240 



Silver... 0.299 



Total 20.539 



Total of volatile portion, slag, and bullion 167. 509 



In these calculations speiss and matte have been purposely neglected. Besides 

 the descending charge of solid matter thrown in the furnace at the feed-hole, there is 

 the ascending charge of blast forced in at the tuyeres. The weight of the gaseous 

 charge will be calculated after the weights of charges filling the furnace have been 

 determined. 



This discussion is carried on for the blast furnace of smelter C, which is shown 

 in Fig. 2, Plate XXXVI, divided into zones of charges and temperatures in accord- 

 ance with the working of this furnace. These zones will be designated hereafter by 

 their temperatures. The zone 900 of the crucible is charged with 12 tons of bullion. 1 



It is assumed that the furnace is in full blast; that the weight of smelting charges, 

 including fuel, is equal to 502.527 pounds, or three times the weight of the charge cal- 



1 Temperatures are theoretical, not observed. 



