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THE POPULAR SCIENCE MONTHLY. 



It consisted of a basin or hearth, b, in which a fire of charcoal or 

 coke was built, the fuel being carried above the level of the 

 water-cooled tuyeres, g g. On this mass of ignited fuel a charge 

 of a ton or a ton and a half of pig iron was thrown, over which 

 fuel was heaped, and the blast (which was regulated by the 

 valves, k k) was then turned on. In about one hour and a half 



the pig iron was 

 melted, and its 

 upper surface as 

 it lay in the 

 hearth was ex- 

 posed to the ac- 

 tion of the blast 

 (oftentimes in 

 the larger refin- 

 eries there were 

 six tuyeres, three 

 on a side, but 

 in some of the 

 oldest refineries 

 there was but 

 one tuyere) ; this 

 effected the oxi- 

 dation and re- 

 moval of con- 

 siderable of the 

 carbon, most of 

 the silicon, and 

 a portion of the 

 sulphur, a large 

 amount of "slag" 

 being formed. 

 About two hours 

 after the com- 

 mencement of the operation the metal was " tapped out " on to 

 the " running-out bed," which was a shallow trough made of very 

 thick castings ; a section of which is shown at n. These cast- 

 ings were provided with flanges, which rested upon the sides, 

 o o, of a box- or channel, p, filled with water to cool the running- 

 out bed, and promote the rapid solidification of the liquid refined 

 iron ; and as soon as this was accomplished the final cooling was 

 hastened by a jet of water forcibly thrown upon the upper sur- 

 face of the metal from a hose. This caused the " cinder " on this 

 surface to separate in a great degree from the refined metal, 

 which, when perfectly cool, was broken up into pieces of manage- 

 able size. The fracture of "refined metal" was white, inclined to 



Fig. 21. Cross-section of a Eefinery. 



