Manufacture of Bar Iron in Southern India. 391 



a large hammer to consolidate it, is- passed between rollers 

 which squeeze out much of the impurities, and form it into 

 " mill bar iron." This is however too impure for use, and it is 

 necessary to cut the rough bars into pieces and to weld them 

 together afresh, in a u reheating furnace," and expose them 

 to another rolling, and even to repeat the operation a third 

 time, before good tough bar iron is produced. In the 

 " puddling furnace" about a ton of coals is expended to each 

 ton of " fine metal," and in the " reheating furnace," about 

 150 pounds more are expended ; and in each operation a 

 loss of about ten per cent, takes place in the weight of metal 

 operated upon. 



8. Upon an average about nine tons of coals are expend- 

 ed in England in forming one ton of finished bar iron, and 

 it is probable, that if the above processes were attempted 

 upon any smaller scale than that of the English works, 

 a still greater quantity would be used. Some of these 

 works cost 27,000/., and turn out 120 tons of bar iron 

 per week. 



9. In France, Sweden, Norway, and parts of Germany, 

 the fuel principally used is charcoal, and the ores are pure 

 oxides of iron r the furnaces are about thirty feet in height, 

 and in shape resemble in great measure the blast furnaces 

 of England. Leathern forge bellows are frequently used to 

 blow them, and the results vary from five hundred weight of 

 cast iron per day, to sometimes five tons. The quantity of 

 charcoal used also varies very much, from one and quarter 

 ton, to two and half tons for each ton of cast iron, according 

 to the nature of the mineral oxide smelted. 



10. The cast iron thus made is treated with charcoal in a 

 refining furnace, not differing much from the English ones, 

 but the metal is not allowed to run out, the operation being 

 continued for nearly five hours, until the metal has become 

 tenacious and adhesive, when it is removed in lumps of 

 about two hundred weight each, which are forged under a 



