ELECTROCHEMISTRY 167 



idea being to first oxidize the metal by air blast and then 

 to finish it while electric current supplied the necessary 

 heat. I have no information that this combination furnace 

 is anywhere in successful operation, but the equivalent of 

 the same operation performed first in the Bessemer con- 

 verter and then on the blown metal transferred into an 

 electric furnace for finishing, is already in regular com- 

 mercial operation at the South Chicago Works of the U. S. 

 Steel Corporation. I have had the privilege and pleasure, 

 thanks to Mr. Heroult, of studying that operation, in com- 

 pany with Mr. Heroult and the editor of Metallurgical and 

 Chemical Engineering. You may find a description of the 

 process in the April number of that journal, so I wiU not 

 repeat it here except so far as to say that 15 tons of the 

 product of the Bessemer blow, oxidized to the extent usual 

 in the Bessemer converter, was kept melted less than two 

 hours on the basic hearth of the electric furnace, treated 

 with two different slags to refine it from phosphorus and 

 sulphur, deoxidized or "dead-melted," and then poured 

 into ingots of steel intended for axles. The steel produced 

 was of better quality than the usual corresponding open- 

 hearth metal, and was produced at slightly less total cost. 

 This combination process bids fair to give a new lease of 

 life to the declining Bessemer steel industry; its economic 

 importance is evident. 



The open-hearth steel furnace is, at present, the most 

 important of the methods of manufacturing steel "ton- 

 nage steel." It makes steel from pig iron and scrap of 

 proper quality, or from pig iron and iron ore (mill-scale), 

 or from pig, scrap, and ore. It makes its best steel on 

 silica hearths from high grade material low in sulphur and 

 phosphorus, and its cheapest steel on basic hearths from 

 almost anything. The electric furnace can do any or all 

 of these things, and, as a general proposition, produce bet- 

 ter steel from given materials than the open-hearth furnace. 

 Under what circumstances it will pay to use the electric 

 furnace instead of the open-hearth furnace would take at 



