Note 971 — BOOK XXXIII. THE NATURAL HISTORY OF METALS.647

Beckmann finds considerable difficulties in this description—“I acknowledge that this passage I do not fully comprehend. It seems to say that the quicksilver, when the gold was laid on too thin, appeared through it, but that this might be prevented by mixing with the quicksilver the white of an egg. The quicksilver then remained under the gold: a thing which is impossible. When the smallest drop of quicksilver falls upon gilding, it corrodes the noble metal, and produces an empty spot. It is, therefore, incomprehensible to me how this could be prevented by using the white of an egg. Did Pliny himself completely understand gilding? Perhaps he only meant to say that many artists gave out the cold-gilding, where the gold-leaf was laid on with the white of an egg, as gilding by means of heat.”—Hist. Inv. Vol. II. p. 295.