B L A 



yeaily finding its way into blaft furnace woil<.<. The regu- 

 lar and increaied effefts of this very powerful machine were 

 foon felt in mod of the iron eonnties. The produce of the 

 furnaces in metal grcatlv incrcafed as to quantity, and as 

 they became more profpcrous, ftimulated others to engage 

 in limilar undertakings. New works were yearly proicftcd, 

 and feveral blowing furnaces annually added to the former 

 lift : (o that in eight years the manufadure of pig-iron had 

 nearly doubled itfelf. 



B L A 



The following table is a curious illuftration of tbis facS. 

 It was drawn up as an authentic document of the returns 

 made from all the Mall furnace proprietors in Britain, of the 

 number of their furnaces, and the annual quantity of pig-iron 

 manufadlured at their rcfpeftive founderies. Thefe returns 

 were made at a time when it was in the contemplation of the 

 legiflature to impofe a tax upon pig-iron, and are copied from 

 Dr. M' Nab's letter to the chairman of the committee of the 

 houfe of commons upon the fubjcit of the coal trade. 



NAMES of all the FURNACES in Great Britain, with the Excife Return of the Qiiantity of Pig Iron 

 made in 1796; the Quantities fuppofed and calculated upon; and the Returns of the Qu^antities 

 really made. 



