ubular bolts, allowing passage of water.
The bridges contain water, and have ascending and descending steam and water pipes.
The puddling-furnace was invented by an iron-master of the name of Henry Cort, about the year 1780, the bed of whose furnace was made of sand, consequently the carburet was refined, many of its impurities, especially the carbon.
which is the metalloid causing fluidity, was driven from it; hence, when the pigiron was melted, it assumed the form of grain.
Mr. Samuel Baldwin Rogers introduced the present system of iron bottoms to furnaces, which obviated the deteriorating influence of the silicon due to the sandy bed of the Cort furnace, and eventually did away with the finery process.
The chamber the pig-metal is charged with consists of iron plates forming the bottom and sides, which are lined with refractory slags rich in oxides of iron.
In changing the heat, slags and scales from the hammers and rollers are thrown on the hearth or bottom, and on this