2340094The New Student's Reference Work — White Lead

White Lead is one of the compounds of lead, called by chemists basic carbonate of lead, and is used extensively in the manufacture of paint. The Dutch process of manufacture is the oldest. Thin sheets of lead are rolled up and put into earthen vessels, which have some weak vinegar at the bottom. These vessels are surrounded with spent tan-bark or some other material which ferments readily, and thus produces heat and gives off carbon dioxide. The pots are thus left for about six weeks, when the lead is found either thickly coated or entirely changed into the white, basic carbonate of lead. This process is thought to give the best material for fine work, and is used in some of the American white-lead factories, but the patent process manufactures it more cheaply. There are 36 white-lead factories in the United States, the largest being at Brooklyn, and the product is 130,000 short tons a year. The lead used is brought from the Rocky Mountain region.