The German white lead is manufactured from the lead of Bleyberg, in Corinthia, on account of its purity.,,The lead is cast by being poured upon a sheet iron plate, and as soon as it begins to fix, the plate is sloped, and thus a sheet of lead is left on it J1/48th or 1/24th of an inch in thickness. By cooling the plate with water, several cwt. of blue lead are cast into sheets in a day.,,Instead of pots, boxes five feet long, one foot broad, and about ten inches deep, are used. The lower part of the boxes is pitched about an inch high; the upper part has sticks placed across. The acid mixture poured into each box is in some manufactories made of a gallon each, vinegar and wine lees ; in others of 20 pints of wine lees, 8 pints of vinegar, and 1 pound of pearl-ash. The vinegar is usually made of crab apples and water.,,The leaves of blue lead being trimmed to a proper size, are doubled and hung over the sticks in the upper part of the box, so as not to touch one another, nor the sides of the box, nor the acid liquor. A cover is then put on; and if a dung heat is used, or the mixture contains pearl-ash, the joints are carefully closed with paper pasted over them. The more usual mode is to dispose the boxes in a large room heated by stoves to about 86 deg. Fahr. a greater heat would evaporate the acid too fast.,,In about a fortnight the corrosion is finished, and tie sheets of white lead are found near 1/4 inch thick, and covered in some places with crystals of sugar of lead. As much a can be got off by a moderate degree of force, is very carefully washed. This washing is esteemed the most delicate part of the whole manufactory; during the progress of it, a white scum appears which is taken off, and a little pearlash beinig added to it, it is changed into white lead, of a beautiful whiteness, and is sold for choice purposes: the remainder is mixed with a pure sulphate of barytes, brought from the Tyrol, in different proportions, according to the market for which it is designed.,