A process of making white lead is described in Zedler's " Universal Lexicon," edition of 1733. It is probably the method in use in Germany at that time. This description varies but little from the practice in Holland and England at that period. The lead was cast in sheets, rolled in spirals, and placed in earthen pots over vinegar ; the pots were then sealed and put in a warm place for four weeks. The whitest and most brittle portions of the resulting white lead, "those pieces thoroughly corroded within and without," were put aside to be sold to the artists. Other portions were ground with water and formed into " blocks like pyramids, and were wrapped in blue paper rather than any other color, so that the white will seem yet whiter." In these papers, it is said, the white lead was sent to Holland and England. 2 ,,2 Zedler, Universal Lexicon, vol. iv., article Bleiweiss.