The early steel works were all located in the vicinity of great forests, for charcoal was the only fuel used. The works were also lo cated near running streams, and water wheels were used to provide power for the blast, and for the first power hammers. There are many such still in use in Sheffield. In Queen Eliza beth's time the iron trade had become so great that the wholesale destruction of forests was stopped, and the position and number of iron works was limited by law. As the result of tbis legislation the iron trade languished until Dud Dudley, in 1620, or a little earlier, success fully used coal in the blast furnace. In his day 20 tons a week was a large output for a blast furnace, while to-day the output of one of the blast furnaces at Homestead is nearly 5,000 tons per week. In primitive processes, the workers took advantage of natural draft and located their furnace on a windy hillside. Later, crude bellows were made from hides and still later a blowing arrangement operated by flowing water was invented. Not much real progress could be expected from such crude devices, and one of the first applications of the steam engine of Watt was running a blow ing engine at the Carron Iron Works in 1760. It was not until 1730 that it occurred to Abra ham Darby and his son to treat pit coal just as his charcoal burners treated wood. His idea, needless to say, was a good one, and coke was produced, which in turn was soon successfully used in the blast furnaces, and is at the present time the principal fuel used in blast furnace practice, although a few charcoal blast fur naces remain in America and are quite com mon in Sweden. The next great advance in the
metallurgy of iron was that of Robert Hunts man, of Sheffield, who first produced crucible steel in the year 1740. As Dr. Percy says, re ferring to Huntsman: ((Formerly, so far as I arn aware, steel was never melted and cast after its production; indeed, by the founding and casting of steel after its production its heterogeneousness is remedied, and ingots of the metal can be produced perfectly homo geneous throughout, and for the practical solu tion of this problem we are indebted to Robert Huntsman, of Sheffield.° Huntsman was by trade a clockmaker, and no doubt had his troubles in attempting to make springs from the crude steel which was avail able in his time. It was to overcome this dif ficulty that he began experiments with a view to melting the cemented, or blister bar, of his day, to obtain a homogeneous product. A grandfather's clock, the pendulum rod and spring of which are supposed to have been made from the first cast steel produced by Huntsman, is still shown in Sheffield. Huntsman's chief difficulty in his investigations was to find the right kind of clay for making crucibles which would stand the intense heat of steel melting. His first crucibles were only 10 inches high, and held about 20 pounds of steel. Steel made by this process was of course expensive, and could only be used for edge tools, dies and drills, for which a great degree of hardness and fine polish was desired. The original business started by Robert Huntsman is still conducted by his lineal descendants of the fifth generation at the present time. See STEEL, MANUFAC