168 MODERN SCIENCE READER 



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 horse-power year, and 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 Pittsburg, with power at $30 and 

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

 for producing such steel as it can produce. However, even 

 here, the combination of Bessemer and electric furnace is 

 possibly cheaper than the all open-hearth process; the com- 

 bination of open-hearth and electric furnace process is quite 

 possible and practicable, to produce crucible-quality steel 

 on a. large (tonnage) scale, and the combination of the 

 open-hearth and electric furnace into one furnace is not only 

 a possible combination, but is actually being "tried-out." 



The latter idea is to take an open-hearth furnace, and to 

 place electrodes in the roof. The furnace is run as an 

 ordinary open-hearth furnace, with the electrodes with- 

 drawn; and at the close of the open-hearth heat, gas and 

 air are shut off entirely, the electrodes lowered into prox- 

 imity to the bath, and the heat finished as an electric fur- 

 nace heat. The idea is sound and practicable, and will 

 result in the production of better steel than can be obtained 

 from any open-hearth furnace, at but a slight advance on 

 the cost of the open-hearth steel, say, $2 to $3 per ton. 



As to the capacity for enlargement of electric steel fur- 

 naces, they started out to duplicate the crucible steel pro- 

 cess, producing 100 pounds of melted steel at a heat, and 

 in eight years have risen to 15 tons capacity. In Europe, 

 an electric calcium carbide furnace of 18,000 kilowatts, 

 capable of producing 200 tons of carbide daily, is in prac- 

 tical operation. A furnace of like power capacity could 

 be built to make steel, and would be a 200-ton steel furnace 

 or larger. We can therefore say with assurance, that with 

 a little more experience and experiment, electrometal- 

 lurgists will be able to furnish the steel maker with electric 

 steel furnaces as large as are wanted up to 200 tons' 

 capacity if desired. 



