EXPLANATION OF PLATES. . XV 



PLATE XV (Page 144). 



IKON. 



Steel smelting. — Bessemer converter. A is the Jjody of the converter; (^ the blast 

 pipe ; F the tuyere box; D the pinion, and li the rack by which tlie converter is rotated; 

 S is the hydraulic cylinder wori<iug the rack R. 



(Cat. No. r)i-202, U. S. X. M. From Kohn's Iron and Steel Manufacture. ) 



PLATE XVI (Page 146). 



IROX. 



Hteel smelting. — Interior of Bessemer steel house, showing converter A, casting crane 

 H, hidle G, with stopper M and mold K. L is a hood, to direct sparks and tiames 

 from the converter up the chimney. 



(Cat. No. 51203, U, S. N. M. From Kohn's Iron and Steel Manufacture. ) 



PLATE XVII (Page 152). 



IRON. 



Pig-iro)i smell :ng. — Section and plan of a typical blast furnace. 



A, air cylinder, opsratiug bell C, for the introductioa of the charge by levers B; D, 

 waste-gas pipe; E, downcomer, carrying gas away to be used under the boilers and in 

 the hot-blast stoves; F, explosion door; G, cleauing door of downcomer; H, gas main; 

 I, extra high tuyere (not used); K, blast pipe, supplying air to the tuyeres; L, water- 

 pipe, supplying water to cool heated portions of the crucible; M, M, tuyeres, through 

 which air is blown into the furuace; N, N, cinder not.hes, for drawing off the cinder. 

 The notch for drawing off the metal is not shown but is similar to the cinder notch, 

 but lower down the furnace, iu front; O, O, columns supporting mantel. This furnace 

 is 74 feet by 19 feet, has an iron mantel supported on columns, and is lined with fire 

 brick. 



(Cat. No. 51004, U. S. N. M. From FackenthaPs Durham Blast Furnace.) 



PLATE XVIIl (Page 1.52). 



Pig-iron smelting. — .Stock floor of a charcoal blast furnace. 



Shows on the right fine-ore bin, next coarse-ore bin. In front of the coarse-ore bin is a 

 buggy, in which ore is weighed, hoisted to the top of the furnace, rolled over the throat, 

 and emptied by lowering the bottom of the buggy. Beyond the ore bin i.-- the charcoal 

 bin and a buggy for charging the charcoal, which is emptied by tipping it over the 

 throat of the furnace onto the bell. At the left is a scale for weighing the charge. 

 Over the ore bin is a rock breaker. 



(Cat. No. 54630, U. S. N. M. From photograph.) 



PLATE XIX (Page 154). 



Pig-iron smeUing. — Cisting-house floor of charcoal blast furnace, showing beds of 

 molten cast-irou that has just been tapped from the furnace, and cast into pigs. The 

 tap hole of furnace is obscure 1 by the glare of the hotiroo. 



(Cat. No. 54633, U. S. N. M. From photograph.) 



