The application of electricity to metallurgical processes has hitherto been confined to the reduction of metals from solutions, and few attempts have been made to effect dry reductions by means of an electric current.  Sir W. Siemens attempted to utilize the intense heat of an electric arc for this purpose, but accomplished little beyond fusing several pounds of steel.  A short time since, Eugene H. Cowles and Alfred H. Cowles of Cleveland conceived the idea of obtaining a continuous high temperature on an extended scale by introducing into the path of an electric current some material that would afford the requisite resistance, thereby producing a corresponding increase in the temperature.  After numerous experiments that need not be described in detail, coarsely pulverized carbon was selected as the best means for maintaining a variable resistance and at the same time as the most available substance for the reduction of oxides.  When this material, mixed with the oxide to be reduced, was made a part of the electric circuit in a fire clay retort, and submitted to the action of a current from a powerful dynamo machine, not only was the oxide reduced, but the temperature increased to such an extent that the whole interior of the retort fused completely.  In other experiments lumps of lime, sand, and corundum were fused, with indications of a reduction of the corresponding metal; on cooling, the lime formed large, well-defined crystals, the corundum beautiful red, green, and blue hexagonal crystals.

Following up these results with the assistance of Charles F. Mabery, professor of chemistry in the Case School of Applied Science, who became interested at this stage of the experiments, it was soon found that the intense heat thus produced could be utilized for the reduction of oxides in large quantities, and experiments were next tried on a large scale with a current from two dynamos driven by an equivalent of fifty horse power.  For the protection of the walls of the furnace, which were made of fire brick, a mixture of the ore and coarsely pulverized gas carbon was made a central core, and it was surrounded on the sides and bottom by fine charcoal, the current following the lesser resistance of the central core from carbon electrodes which were inserted at the ends of the furnace in contact with the core.  In order to protect the machines from the variable resistance within the furnace, a resistance box consisting of a coil of German silver wire placed in a large tank of water was introduced into the main circuit, and a Brush ammeter was also attached by means of a shunt circuit, to indicate the quantity of current that was being absorbed in the furnace.  The latter was charged by first filling it with charcoal, making a trough in the center, and filling this central space with the ore mixture, which was covered with a layer of coarse charcoal.  The furnace was closed at the top with fire brick slabs containing two or three holes for the escape of the gaseous products of the reduction, and the entire furnace made air-tight by luting with fire clay.  Within a few minutes after starting the dynamo, a stream of carbonic oxide issued through the openings, burning usually with a flame eighteen inches in height.  The time required for complete reduction was ordinarily about an hour.