ELECTROCHEMISTRY — RICHARDS. 181 



There are also varieties of methods of manufacture of steel, aside 

 from the melting together of highly pure materials as in the crucible 

 method, winch are equally available in most types of the electric 

 furnace. The Bessemer converter takes liquid pig iron as it comes 

 from the blast furnace and by rapid oxidation by air blast converts 

 it into steel. Mr. Heroult has tried to combine the Bessemer con- 

 verter with the electric furnace in one apparatus the 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 

 converter and then on the blown metal transferred into an electric 

 furnace for finishing is already in regular commercial operation at 

 the South Chicago Works of the United States Steel Corporation. I 

 have had the privilege and pleasure, thanks to Mr. Heroult, of study- 

 ing that operation, in company 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 will 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 eco- 

 nomic importance will appeal particularly to this audience. 



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

 of the methods of manufacturing steel — "tonnage 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 any- 

 thing. The electric furnace can do any or all of these tilings, and, as 

 a general proposition, produce better 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 least one lecture to discuss; we will not go deeply into it here. 

 In Europe, countries which have very cheap water power, around $10 

 per horsepower year, aDd fuel costing $4 to $6 per ton, are finding the 

 electric furnace the cheaper; with power costing $20 and coal $5, the 

 two are about on equal terms; in Pittsburgh, with power at $30 and 

 coal at $1, the open-hearth furnace is by far the cheaper for produc- 



