112 



Zinc Desilverizatinn 



The following tables, taken by myself, from the book 

 give a summary of the work for April and May, 1880 : 



Metallic dross from refining furnace, in per cent, 

 of gross charge, ----- 



0. 85 of lead and skimmings, 



1st net weight in desilverizing kettles, 1,000, 



1st crass from " " 



2d net weight " " 96.34, 



1st average assay of kettles, - - . 



2d " " " - . . 6 



1st Grasses in per cent, of 1st net metal in desilver- 

 izing kettles, ----- 



Retort in per cent, of 2d desilverizing kettles, - d 



Zinc used in per cent, gross charge, 



"1st net weight in desilverizing kettles 

 " " per cent, of merchants' lead. 



Coal used per ton of gross charge, 

 " merchant lead. 



Lead in merchant lead, - - 



" retort Grasses, - - . - 



" refining skimmings, 



Apparent gain, 0.53 per cent , 

 The losses and gains are apparent only. 



a Charge for the retorts calculated on this, b Average assay, c Per centage of 96.34. 

 d Per centage of 88.50. e Per centage of 96.34. 



The lead made by the Germania, Peniisylvania Co. and St. 

 Louis works is exceedingly fine. As it can be used for the manu- 

 facture of white lead, it commands the highest market price. 



The following analyses, made by Dr. O. Wurth and Dr. Zuireck, on a 

 sample from the works of the Pennsylvania Lead Company, show that the 

 lead is equal if not superior to any of the brands produced abroad : — 

 In 100 parts. Dr. O. Wurth. Dr. Zuireck, Dr. O. Wurth. Dr. Zuireck, 



s of thf 



. Company, 



April. 



May. 



.078 





2.88 



2.47 



96.34 



97.53 



7.84 



7.55 



88.50 



89.98 



144.67 



172.73 



132.64 



160.92 



8 58 



8.04 



7.54 



8.32 



1.37 



1.59 



1.43 



1.68 



1.72 



1.98 



192.16 



208.00 



238.00 



262.00 



90.47 



88.99 



6.78 



7.47 



8.28 



3.48 



100.53 



99.94 



Loss 1.06 per cent. 



Silver, 



Antimony, 



Copper, 



Zinc, 



Iron, 



Sulphur, 



Arsenic, 



Bismuth, 



0.00042 

 0.00051 

 0.00007 

 0.00038 

 trace. 

 0.00018 

 none. 



Berlin. 

 0.00035 

 0.00254 

 0.00094 

 0.00070 

 0.00082 



0.03843 



0.00016 

 0.00318 

 0.00005 

 0.00122 

 0.00013 

 0.00023 

 trace 

 0.02746 



Berlin. 



0.0007a 



0,00346 

 0.00093 

 0.00075 

 0.00082 



0.04594 



In conclusion, I beg to express my thanks to Mr. Faber du 

 Faur, for working-drawings of his furnaces, to Mr. Weisse, of the 

 Germania Works, and to Mr. Enrich, of the Pennsylvania 

 Works, for the many interesting details furnished me by them 

 while visiting their works for the preparation of this article. 



