Pattison’s process

Richardson prepares white lead by taking the crystals obtained in the desilverizing of ordinary lead by Pattison s process, or metal otherwise reduced, and mixing with it from one to one and a half per cent, of vinegar, or a proportionate quantity of nitric acid, acetate or nitrate of lead diluted with water and after turning the mixture over repeatedly, placing from twenty to thirty hundredweight of the mixture upon the shelves of a chamber lined with lead, slate, or stone. 

The silver obtained from the cupelling furnace represented in Figs. 402 and 493, as well as the rich lead concentrated by PattiSon s process, still requires further purification, and for this purpose it is subjected in both cases to cup citation on a small scale, with a cupel or teat made of bone-ash. Figs, 494 and 495... 

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