K:^]SrSJ>i.8 CITY 



Review of Science and Industry, 



A MONTHLY RECORD OF PROGRESS IN 



SCIENCE, MECHANIC ARTS AND LITERATURE. 



VOL. V. NOVEMBER, 1881. NO. 7. 



CHEMISTRY AND METALLURGY. 



JOPLIN CITY WHITE LEAD WORKS. 



BY ERASMUS HAWORTH. 



The visitor to Joplin City, Mo., should not fail to see the white lead manu- 

 facturing establishment of that city. For centuries past white lead has been used 

 very extensively in almost all kinds of paints. The process of its manufacture, 

 until within the last few years, has been very simple in practice, although a little 

 complicated in chemical action. The oldest process of which we have any ac- 

 count consists simply in hanging spirally-shaped strips of sheet lead over open ves- 

 sels of fermenting vinegar. In a few days the strips of lead become covered with 

 white lead. This is then scraped off, the strips replaced over the vinegar, and 

 thus the operation repeated indefinitely. 



The vapor of acetic acid, rising from the vinegar, acts upon the surface of 

 the lead forming a basic acetate of lead. The carbonic oxide liberated by the 

 fermentation of the vinegar subsequently breaks up the sub-acetate, forming as 

 the principal resultant lead carbonate, or white lead. 



Another process, similar chemically, consists in dissolving litharge {lead oxide) 

 in acetic acide until the triplumbic acetate is obtained. Through the solution of 

 this salt carbonic oxide is passed until the whole of the triplumbic acetate is con- 

 verted into lead C2iX\)0XidX^ {Tvhite leid) and neutral lead acetate. Upon boiling 

 the neutral lead acetate with litharge more triplumbic acetate is produced, so that, 

 with the exception of the unavoidable loss in the manipulations, a given amount 



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