1 igure 10. — Electric furnace for pro- 

 DUCING elemental phosphorus, invented 

 by Thomas Parker of Newbridge. England, 

 and assigned to The Electric Construction 

 Corporation of the same place. The 

 drawing is part of United States patent 

 482,586 (September 13. 1892). The fur- 

 nace was patented in England on October 

 29, 1889 (no. 17,060); in France on June 

 23, 1890 (no. 206.5661; in Germany on 

 June 17, 1890 (no. 55.700); and in Italy 

 on October 23, 1890 (no. 431). The 

 following explanation is cited from the 

 U.S. patent: 



Figure 1 [shown here] is a vertical section 

 of the furnace, and Fig. 2 is a diagram to 

 illustrate the means for regulating the electro- 

 motive force or quantity of current across the 

 furnace. 



F is the furnace containing the charge to 

 be treated. It has an inlet-hopper at a, with 

 slides A.\, by which the charge can be admitted 

 without opening communication between the 

 interior of the furnace and the outer air. 



B is a screw conveyer by which the charge 

 is pushed forward into the furnace. 



c'c' are the electrodes, consisting of blocks 

 or cylinders or the like of carbon fixed in 

 metal socket-pieces c c, to which the electric- 

 circuit wires d from the dynano D are affixed. 

 The current, as aforesaid, may be either con- 

 tinuous or alternating. c-c % are rods of metal 

 or carbon, which are used to establish the 

 electric circuit through the furnace, the said 

 rods being inserted into holes in conductors 

 c 3 (in contact with the socket-pieces c) and in 

 the furnace, as shown. 



g is the outlet for the gas or vapor, h the 

 slag-tap hole, and x the opening for manipu- 

 lating the charge, the said openings being 

 closed by clay or otherwise when the furnace 

 is at work. 



I use coke or other form of carbon in the charge between the 

 ele< Wf', the said coke being in contact with the said elec- 

 trodes, so that complete incandescence is insured. 



A means for varying the electro-motive force or quantity of 

 current across the furnace with the varying resistance of the 

 charge is illustrated by the diagram, Fig. 2. c' c 2 indicate the 

 electrodes in the furnace, as in Fig. 1, and D is the dynamo 

 and T its terminals. E represents the rxi iting-circuit. R R 



T. PARKER. 



ELECTRICAL FURNACE. 



No. 482,580 



Patented Sept. 13, 1892. 



TfUntssts- 



foL/ZurM 





are resistances, and R S is the resistance-switch, which is 

 operated to put in more or less resistance at R as the resistance 

 of the charge in the furnace lessens or increases. This switch 

 may be automatically operated, and a suitable arrangement 

 for the purpose is a current-regulator such as is described in 

 the specification of English Letters Patent No. 14,504, of 

 September 14, 1889, granted to William Henry Douglas and 

 Thomas Hugh Parker. 



BULLETIN 240: CONTRIBUTIONS FROM THE MUSEUM OF HISTORY AND TECHNOLOGY 



