Characters. - A soft, heavy, white powder, blackened by sulphuretted hydrogen.

Solubility and Reactions. - Insoluble in water, soluble with effervescence in diluted acetic acid without leaving any residue, and forming a solution which gives the reactions of lead.

Preparation. - By exposing lead to the fames of vinegar and to C02.

Impurity. - Calcium.

Test. - The acetic solution when treated with excess of sulphuretted hydrogen, boiled and filtered, gives no precipitate with oxalate of ammonium.

Preparation. b. and U.S.P.

Unguentum Plumbi Carbonatis.........1 part in 8, B.P.; 1 in 10, U.S.P.

With simple ointment, B.P.; with benzoated lard, U.S.P.

Uses. - Carbonate of lead is used as an application to excoriated surfaces, piles, boils, and ulcers. The ointment is used in the same way.