White flake is lead corroded by means of the pressings of the grape; and consequently in fact a ceruss prepared by the acid of grapes. It is brought here from Italy; and far surpasses, both with regard to the purity of its whiteness, and the certainty of its standing, all the ceruss, or white lead, made here in common. It is used in oil and varnish painting for all purposes, where a very clean white is required: but no kind of ceruss ought to be used in water colours for paintings that are intended to endure time; as it will generally turn black; and appear, at length, as if the lead itself had been used instead of any preparation of it.,,