m the Manufacture of Malleable Iron. %yj 



light blue, fibrous, and tearing considerably in groups. It 

 poffefled, however, a flight degree of red-ftiortnefs when 

 very highly heated. It formed with equal facility horfe- 

 fhoes and nails of the mod delicate ftru&ure. The produce 

 of the raw ore never exceeded 47 per cent., and commonly 

 was from 43 to 45. Iron of a more pure fra&ure was 

 obtained by piling the ore upon a flat cake of fire-clay or 

 iand-ftone. As the welding heat penetrated the mafs, part 

 of the earth and unmetallized particles of iron were reduced 

 into fi-fion, and run off into the furnace. The produce, 

 however, in ron was reduced as low as 37 per cent. This 

 reduction of metal, no doubt, arofe from the greater furface 

 expofed in this way than when the balling pot was ufed. 



To obviate this, and, at the fame time, infure an equal 

 quality of iron, the piles were heated in the fame furnace 

 with the gas of coaks, and the flue of the furnace nearly flint 

 up ; fo that the circulation of air was much fmaller, and the 

 heat, though equally great, yet more attenuated. This pro- 

 duced a better quality "of iron than any of the former ways, 

 but at a greater expenfe of fuel. 



However fuitable this iron was for the common nfes of the 

 fmithy, it was found to form but a very indifferent quality of 

 fteel By cementation. The whole of it became in fome de- 

 gree laminated, and incapable of ftanding great fatigue ; and 

 the red-fhortnefs, which before faintly marked the bar iron, 

 was how confiderahly increafed when in the ftate of fteel. 



In varying this procefsof making bar iron, quantities of the 

 prepared ore were thrown upon the top of a fmall finery 

 fire, charged with foft coal coak, and funk to the bottom. 

 The metallic mafs was found connected, and fo much puri- 

 fied as to afford iron of a clear fracture, but the produce was 

 diminifhed to 28 and 30 per cent, from raw ore. 



The fame ore, however, funk in a fmall fire of wood char- 

 coal, yielded a very fuperior quality of the metal to any of 

 the former. In point of quality and fra&u re, it was deemed 

 no way inferior to many of the bed Swedifh marks. Still, 

 however, it mult not be denied, that this iron formed com- 

 paratively but an inferior quality of fteel. In this ftate I left 

 this procefs for making bar iron, and have not yet found 

 time nor fufficient opportunity to refume it. Of late years I 

 underftand a procefs, fomewhat fimilar, has been eftaolifhed 

 near Whitehaven, in the neighbourhood of the Cumberland 

 iron -mines, but abandoned, not becaufe the quality of iron 

 was inferior, but I believe from a want of eeconomy in the 

 procefs itfelf. 



A thoufand unforefeen difficulties occur in ftriking out a 



new 



