MannfaBUre of Pig-iron <ivith Pit-Coal. ^<.)^ 



To evade the mode of operation difcovered by Dudley, <it 

 to introduce the making of pig-iron with pit-coal to greater 

 «dvantage, a new plan was adopted by Captain Buck, Major 

 Wildman, and others, in tlie foreli of Dean, where thev 

 crefted large air-furnaces, into which thev introduced large 

 clay pots, rcfembling thofe ufed at glafs-houfes, filled with 

 various proportions of the necellarv mixture of ores and char- 

 coal. The furnaces were heated by the flame of pit-coal, 

 and it was expelled that, by tapping the pots below, the fc- 

 parated materials would flow out. This rude proeefs was 

 found entirely impracSlicable ; the heat was inadequate to 

 perfeA feparation, the pots cracked, and in a fliort time the 

 proeefs was abandoned altogether. 



The misfortunes which fuceeffively betel the unfortunate 

 Dudley, ariling from rivalfliip in the iron bufmefs and his 

 attachment to the royal caufe during the civil wars, prevented 

 his improvements from being elofely followed up. The re- 

 fufal of a new patent after the reft;oration prevented him 

 from again entering into the bufinefs with his ufual enter- 

 prife. From that period till about the year 1740, nothing 

 of importance was dune in the manufacture of coke pig-iron. 

 The application of the Aeam-enginefor railing and compreff-" 

 ing air, no longer confined the manufaeturer to local fitua- 

 tions. Larger furnaces, with a proportionate quantity of blall, 

 were introduced. Among the firfl efletls, from 8 to 10 tons 

 of pig-iron were produced weekly. Ever fincc, the weekly 

 (quantity has in general been increafing. The produce being 

 confiderably dependent upon the quantity of air ufed for re- 

 dutlion, it is now fo well unc'.erftood, that at feme works th£ 

 blowinff-machine is calculated to produce frequently 40 tons 

 of melting pig-iron per week at c:ich furnace. At fome iron- 

 works in Wales, where oxygenated crude iron is manufac- 

 tured purpofelv for converting into bar-iron, there are fcvcral 

 intiancesof a furnace producing 70, 71, and 72 tons of metal 

 Weekly. This aftonifliing quantity forms a molt (triking con- 

 trail with the early exertions of Dudley, who conceived three 

 tons a profitable produce, and whofe greatefl exertions never 

 exceeded 7 tons of pig-iron weekly. 



Afler this flight flictch 'A' the lirogrefs-of niauufatSluring 



pig' 



