3^ Ort the Origin and Pro.grcjs of the 



periods, to prove the flow but fleady progrefs of improvement. 

 A comparifon betwixt the cffecls produced by the ufe of 

 charred wood and pit-coal in the blalt-furnace Vvill alia 

 afford fubje(S for a few reflexions. 



It would appear that, towards the clofe of queen Eliza- 

 beth's reign, blaft-funiaces had been conftru6ted of fize fuf- 

 ficient to produce, with ores and the charcoal of wood, from 

 3 to 3 tons per day, or from 15 to 21 tons of pig-iron fer 

 week. Such great produces in iron at this early period were, 

 however, confined to fituations where there was abundance 

 of \Aatcr, and where water-wheels and leathern bellows of 

 confidcrable magnitude were ufcd. The more common 

 modes of operation were 'confined to furnaces of an inferior, 

 fize, where air was fupplied by means of bellows excited by 

 cattle or the labour of men. 



As the manufafture of cannon, mortars, &:c. was at this 

 period onfiderable, and as pit-coal had not yet been applieil 

 to any branch of the manufafturing of iron, it is probable 

 that thefe articles would be caft from the large blaft-furnaces 

 at once 3 the flame of wood not being well calculated for 

 heating the large reverberating furnace where fuch hc^vy 

 pieces of ordnance are now calt, and where feveral tons will 

 be melted in one furnace by the flame of pit-coal ; the non- 

 application of pit-coal, cither to ihe fmelting of ores or melt- 

 ing of iron, would greatly retard the improvement of the 

 fmallcr branches of the caiiing department. Tiie dilficulty 

 with which moll EnglilTi charcoal pig-iron melts, and its 

 almo-ft: immediate tendency to be converted into malleable 

 iron in an air-furnace, would, in every attempt to improve- 

 incnt, prcfeni an infurmountable obfiacle. 



This would appear, amongll others of inferior note, to be 

 the chief reafon why the iniproveincuts of cafting of every 

 denomination have only kept pace with the original iuvcu- 

 tlon and improvement of call iron with pit-coal char. 



From the time of the invention by Dudley till about 60 

 years ago, a period of 120 years, the manufatlure fctms to 

 have fallen aflccp: and it is onlv during the hit 40 vcais 

 that we can no.e a rapid improvement in the fabrication ot 

 callings. The uuiverfal application' of pig-iron, in almoil 



every 



