Document QkpbJKGaakZ2naXrOwX1aLEyE

Kbits lsad has bssn known and used as a pigmant for cen turies; tha Romans and Oraaka uaad the native oarbonats of lead or "oeruaae," as It wae than oalled, from which the minaralogioaX name eerusait# has arisen* X>,i natural pigmant la found only in comparatively small quantities, end it is no wonder that a process for the artificial production of white lead was soon found out and adopted, with the result that natural oeruaslte la not now used as a pigment . It is not known whan white lead was first mode, who node it, or. to vnnt country it owes its birth.. The oldest known method la that commonly called the "Dutch method," from the supposition that it was invented in Holland; it is described as tho Dutch procost in an English patent granted in 1787, end there is no doubt but that It it the rrccess referred to in three earlier patents granted in 1622, 1636, and 1745, in wMoh it Is spoken of aa an old process. Evidently white lord has been made for several centuries. Daring all this period there ha3 been but little change mode in tho Dutoh process. But in the interval inventors hove not be-.*n idle, for there is no other pigment which has attracted 90 attention et their hands e white lead; and the number of processes end modifications of processes *ioh hav'i been devised, is almost innumerable. TVjth ell this invention, the ancient Dutch process still retains its pre-eminence as tve beet prooese for the manufacture of white lead. i \% I i * > l \ i j 0007-SWP-000007357 a J n.3 j 1