Morning journal and courier., 1886-02-22
eentage of carbon compared with the

eentage of carbon as compared with the other constituents.
 When the bars are taken from the cool oven their surfaces are covered with blisters; hence the name 'sblister steel, in which con dition it was formerly used largely for the making of cutting implements. In this State the steel is brittle glass, and it is broken up into bits of pound weight, or perhaps less, put into plumbago crucibles, and melted. The melting requires an intense heat of sev- eral hours duration, each crucible contain ing about fifty pounds of steel. The melted metal is poured into cast iron moulds of square section or of cylindrical form, the moulds being set on end. If the top of the ingot does not shrink inward in cooling it is regarded as evidence that it is unsound- full of air bubbles-and the only remedy is to break up and remelt the defective ingot, as no after working can make it sound. After relocating, the ingots are worked and drawn under hammer and between rolls and made into bars of varying sizes, round and square, and fiat. This is the true least steel' of commerce, Ecutlery steel," or "erucible steel.'
 For the production of building and rail road steel, known generally as "Bessemer steel,' the materials used and the processes employed are entirely different from those used and employed in the making of crucible steel This ''deearbonized,' mild" "erude, Flow, ," or 'Bessemer steel is made from cast iron, and sometimes from the crude iron ore. There are several processes but they all have the same object-the burn ing out of some of the carbon as we'll as all the phosphorus and sulphur, and the return of Q specific amount of carbon to the melted mass to make the particular variety of steel desired. This steel is not adapted to the manufacture of cutting tools, being incapable of being hardened and drawn to any temper required, as good crucible cast steel is.
 A brief description of the usual Bessemer process will serve to give an idea of the meth cd of converting pig iron and ore into the or dinary building steel. The selected iron and ore-if ore is used-are melted into cupola just the same as for making castings in any foundry. From the cupola-or cupolas, for there is usually pair of them to make the process continuous melted iron is run into an immense "converter," pear-shaped pitcher with capacity of from seven to ten tons. This converter is made of thick wrought iron plate like steam boiler plate, and is lined with cement of ground flint and quartz, as fire clay, such is used to line cupolas with, where cast iron is only mel ted, would not withstand the heat necessary to "convert" the iron. The converter is mounted on trunnion like huge mortar for firing bombs. These trunnions are hollow, and through them powerful, continuous blast of compressed air, at a pressure of from fifteen to twenty pounds to the square inch, is driven by Blowing cylinders into the melt ed iron, causing it to bubble and rumble like rapidly boiling water. This burns out the phosphorus, sulphur, and about ten per cent. of the carbon. To compensate for the destruction of the carbon a certain amount of spelgel eisen German for mirror iron, is in troduced. This iron is rich in carbon.
 The progress of the process of converting is ascertained by the experienced workman, or the manager, by the color of the products of combustion as they rush out of the open top of the converter At first there is blue | ish smoke dense and dark, with streaks of scintillant flame; then there is dark red flame, changing to one of brighter red, to l yellow, and finally to an intensely brilliant l white flame; the entire process requiring from fifteen to eighteen minutes.
 At the end of this time the blast is shut | off, the converter tipped forward on it's trun- nions, and the melted metal poured into l moulds, forming ingots, weighing for rails | sometimes 5000 pounds each. These ingots | relocated, reduced under steam ham ner, and passed through rolls, coming out rails for railway purposes.