Note 1053 — BOOK XXXIII. THE NATURAL HISTORY OF METALS.647 (continued 2)

“Nuper credi cœptum certiorem imaginem reddi auro opposito aversis.”—“Of what Pliny says here I can give no explanation. Hardouin (qy. if not Dalechamps?) is of opinion that mirrors, according to the newest invention, at that period were covered behind with a plate of gold, as our mirrors are with an amalgam. But as the ancient plates of silver were not transparent, how could the gold at the back of them produce any effect in regard to the image? May not the meaning be that a thin plate of gold was placed at some distance before the mirror, in order to throw more light upon its surface? Whatever may have been the case, Pliny himself seems not to have had much confidence in the invention.”—Beckmann, Hist. Inv. Vol. II. p. 62.