or White Lead, is a substance so much used in painting, and for other purposes, that numerous modes have been employed for the preparation of it. Of the most common of these, a sufficient account has been given in the Encyclopaedia (see Ceruse, and the same word Chemistry-Index); but Lord Dundonald has discovered a more expeditious and facile method than any of them, which becomes the more useful, as the substance with which it is effected has been hitherto rejected by the chemical world as a caput mortuum.

His lordship directs common lead to be reduced to a calx, but not too fine, and to have a proportion of five-sixths thereof, intimately mixed with muriate, or solution of potash. In this state, he directs it to be frequently stirred, in order to have the new surfaces of the mixture exposed to the carbonic acid of atmospheric air; so his lordship observes, that the effects of the carbonic acid on the alkali existing in the present state of the mixture is essentially necessary, in order to effect the intended purpose. In this state, it is to be frequently sprinkled with water; and, after the calx has been long enough immersed with the muriate to be sufficiently operated upon, the muriate is to be levigated, by com- For this discovery, his lordship obtained a patent on the 18th of August 1797; and the success which has attended the former patents of this scientific nobleman leads us to conclude, that the present discovery is entitled to the attention of the public.