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



The chief characteristic of this furnace lies in the means employed for insulating 

 and moving the carbon holders. The mechanism is clearly shown in figs. 6 and 7. 

 A conical hole tapering outwards is bored in the centre of the covers of the cylinder, 

 and receives a cup-shaped insulating bush (D) of ebonite or red fibre. & central 

 plug E is provided with a mushroom-shaped end which fits closely into this cup and 



Fig. 7. Small high-pressure furnace. 



is lightly drawn against it by means of the nut N placed on the outside, this nut in 

 turn pressing on the insulating ebonite washer I. 



The gas pressure itself forces down this plug firmly on its seat and secures a 

 satisfactory joint. The upper end of the steel plug contains the necessary stuffing 

 box (S) through which passes the feeding rod R. 



From each cover of the furnace project three steel pillars, carrying at their 

 extremities a thick triangular plate M of insulating material. To the centre of this 



