44 KANSAS CITY REVIEW OF SCI EN 



" German steel is blister steel rolled down into bars. It is used mainly for 

 tires and common springs, and is being rapidly superseded by the cheaper grades 

 of cast steel. 



" Shear steel is made by taking a high heat on blister steel and hammering it 

 thoroughly. Double shear steel is made by cutting up shear steel, piling it, heat, 

 ing it and then hammering again. The best shear steal must be made from the 

 best wrought iron. The shear steels are very useful on account of their tough- 

 ness, and the ease with which they can be welded to iron, and when of good 

 quality and well worked, they will hold a very fine edge. 



"Crucible steel is made by melting in a crucible either blister steel or blis- 

 ter and wrought iron, or wrought iron and charcoal, or wrought iron and scrap 

 steel 5 or, in short, a great variety of mixtures, which depend upon the quaUty of 

 steel to be produced. 



" Crucible steel can be applied to any purpose for which steel is used. Gen- 

 erally, it is better than any other steel — that is to say, crucible steel made by 

 melting bUster steel, and tempered to suit by mixing iron of the same grade in 

 the crucible, is always better than German or shear steel made from the same 

 blister. 



" Bessemer steel is made by blowing air through melted cast iron, thus burn- 

 ing silicon and carbon out of the cast iron. After the silicon and carbon are 

 burned out, melted spiegeleisen, or ferro-manganese, is added to the charge. 

 The carbon in the spiegel recarbonizes the steel to the desired point, and the 

 manganese unites with and removes the oxygen which the air used leaves in 

 the steel. 



"Open-hearth steel is made by melting, in a very hot furnace, a charge of 

 pig iron; to this melted iron, which is called the " bath," is added, either wrought 

 iron or scrap steel or iron ore, and the whole is kept hot until all is melted. The 

 wrought iron, or scrap, or ore, reduce the carbon and silicon in the bath to such 

 proportions as are desired in the steel. 



" Bessemer and open-hearth steel are much ahke in quality. They are used 

 mainly for rails, boiler plates, ship plates, bridge and other structural purposes, 

 and machinery. The better qualities are also used largely for springs. The best 

 spring steel, like the best tool steel, is simply that which is made from the best 

 material. Quality of material, chemically speaking, being equal, the best spring 

 steel is that which is made from crucible cast steel, as the crucible process is less 

 crude than either of the others.— ^^^ of Steel. 



ARIZONA COAL. 



Allusion has heretofore been made to the discovery of large and valuable de- 

 posits of coal in Arizona. The location of the fields is near Saddle Mountain, 

 twenty miles northeast of the junction of the Gila and San Pedro rivers, on the 

 upper waters of Deer Creek. Some weeks ago a man brought in specimens of 



