100 



Zin c Des ilver ization . 



alloy at a time. Each, retort has a condeuser, h, attached to it, 

 and in front of it a charging-table, /, covered with cast-iron. 



It is necessary to remoYC the condenser, as in the other furnaces, 

 to clean the retort. The furnace is tapped on the back side, at 

 e, from holes \ of an inch in diameter, bored throngh the bottom 

 of the retort, into moulds placed on the iron ledge, g. 



If the material charged is clean, the time required for an oper- 

 ation is 12 hours. If it is not, it may require as much as 24 

 hours, depending on the quality of the material charged. One 

 man does the work of the six retorts. The amount of fuel re- 

 quired is one ton of coal for one ton of alloy. The results do 

 not differ materially from the other furnaces, except that the 

 operation is longer. They were constructed in the now abandon- 

 ed works at Bloomfield, N. J., and in the works of Messrs. 

 Tatham, in Philadelphia. 



The following tables of the results of the Avorking of this furnace have 

 been prepared for me by Mr. C KirchofE, Jr., who had charge of these 

 furnaces while they were working : — 



Table of charares in the Brodie furnace. 





No. of 



shifts of 



12 hrs. 



No. 1 = 



19 



«* O 5 



17 



" 35 



21 



" 4 



26 



" 5 



26 



" 6 



28 



with hot air 



28 



Lbs. of 

 zinc scum 

 liquated in 



kettle. 



Lbs. of bit. 

 coal used for 

 distillation. 



9,916 

 13,656 

 19,944 

 19,622 1 

 27,324 1 

 21,114 1 

 17,300 1 



22.000 



26,000 

 14,000^ ) 

 with 1 ton I 

 of coke. ) 

 34,000^ 



20,000 



No. of I Yield 

 ^barrows in 

 of I rich 

 charcoal lead. 



No. of 

 charges. 



8,681 

 10,862 

 14,511 

 19,015 

 23,738 

 11,927 

 14,902 



65 

 66 

 60 

 78 

 73 



83, 



1. Mixed with copper scum. 1ft scum at first kept separate, but not afterwards. 



2. Four retorts were still good. 



3. A barrow contains about four bushels. 



4. Jg anthracite and 3^ bituminous. 



5. Nos. 1, 2, and 3 yielded 4,049 lbs. of zinc regained. 



