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MESSRS. R. S. HUTTON AND J. E. PETAVEL ON ELECTRIC 



Small Furnace for High -Tension Currents. 



Since there are a considerable number of electric furnace reactions, as, for instance, 

 most gas reactions, for which very high-tension currents are necessary, it was decided 

 to complete the equipment by providing a furnace specially for this class of work. 



In this case a large capacity, instead of being an advantage, would constitute a 

 serious drawback, owing to the difficulty of preparing and purifying such a quantity 

 of gas. Moreover, in the case of a high-tension arc, the natural temperature gradient 

 is so steep that the maximum temperature is easily and safely attained even in a 

 small enclosure. The rapid rate of cooling which results from the proximity of the 

 arc to the cold walls of the furnace is also of material advantage. 



Fig. 5. Sectional view of small furnace. 



The body of the furnace is suspended from a cast-iron plate A bolted to a wooden stand B. 



The two ends KI, K 2 are closed by covers which carry the feeding mechanism (see fig. 6). The body 



of the furnace is surrounded by a water jacket W. 

 A little below the centre the walls are thickened up to 2 inches and are pierced by two openings. 



The inlet valve screws into H, and a window (see fig. 4) into G. 



The smaller furnace is of one-tenth the capacity of the larger, and consists of a mild 

 steel cylinder about 3 inches internal diameter, with walls \\ inches thick, surrounded 

 on the outside with a water jacket (see fig. 5). The walls are thickened up a little 

 below the centre, and two openings are bored in the ring thus formed. One of these 



