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CHAPTER XXIV.
THE  DECEPTIVE  APPEARANCE  OF  THE FRACTURE   OF PIG IRON.*
Progressive furnacemen and foundrymen have experienced few changes in their practice that have been more radical in character or far-reaching in benefit, than those made by the adoption of chemical analysis to correctly define the grade of pig iron. The change was such a sensible one that many are annoyed that in this age of science they have not always utilized chemistry in their practice. And not until we bring to mind the old-time prices paid for castings, can we realize why commercial success was at all possible to many following the old school methods of judging the grade of pig iron. While the benefits obtained by adopting chemical analysis in foundry practice are generally very great, the advance has been slow. This is on account of the prejudice, selfishness, and conservatism that all new departures in any calling must meet and set aside. The opposition that existed, and is yet in force, against the adoption of grading by chemical analysis has caused the author to expend much time and money in its defence. It is often interesting to investigate the reasons for rejecting the new-school practice that members
* A revised edition of a paper presented by the author to the Pittsburg meeting of the American Foundrymen's Association, May, 1899.tunately, sulphur and phosphorus will not go as readily as manganese and silicon, in fact, in the ordinary refining of a bed they will not go at all; hence the value of refining is to be looked for in the removal of the mechanically mixed slag, the lowering of the silicon and manganese, and, in some cases, the carbon contents, with the consequent increase in the combined carbon of the product and the closing up of the grain.osphorus, as well as sulphur, than a coke or anthracite pig metal.iven is simply an average of the whole, generally taken from the two ends andith the uncertainty of furnace workings when in urgent need of ten hundred             jon of iron; and Sir........................    2,720     "