Note 23 — Chapter II · (continued 2)

One of the professors being employed in restoring a piece of Coreggio, analyzed the mode of colouring. Upon the chalk, he said, the artist appeared to have laid a surface of prepared oil, which then received a thick mixture of colours, in which the ingredients were two thirds of oil and one of varnish; that the colours seemed to have been very choice, and particularly purified from all kind of salts, which in progress of time eat and destroy the picture; and that the before-mentioned use of prepared oil must have greatly contributed to this purification by absorbing the saline particles. It was, moreover, his opinion, that Coreggio adopted the method of heating his pictures, either in the sun, or at the fire, in order that the colours might become as it were interfused, and equalized in such a way as to produce the effect of having been poured, rather than laid on. Of that lucid appearance which, though so beautiful, does not reflect objects, and of the solidity of the surface, equal to the Greek pictures, he remarks, that it must have been obtained by some strong varnish unknown to the Flemish painters themselves, who prepared it of equal clearness and liveliness but not of equal strength. See vol. i. p. 49.