Chap. CCXXX.—How to paint a Picture that will last almost for ever.
After you have made a drawing of your intended picture, prepare a good and thick priming with pitch and brickdust well pounded; after which give it a second coat of white lead and Naples yellow; then, having traced your drawing upon it, and painted your picture, varnish it with clear and thick old oil, and stick it to a flat glass, or crystal, with a clear varnish. Another method, which may be better, is, instead of the priming of pitch and brickdust, take a flat tile well vitrified, then apply the coat of white and Naples yellow, and all the rest as before. But before the glass is applied to it, the painting must be perfectly dried in a stove, and varnished with nut oil and amber, or else with purified nut oil alone, thickened in the sun[1].
- ↑ The French translation of 1716 has a note on this chapter, saying, that the invention of enamel painting found out since the time of Leonardo da Vinci, would better answer to the title of this chapter, and also be a better method of painting. I must beg leave, however, to dissent from this opinion, as the two kinds of painting are so different, that they cannot be compared. Leonardo treats of oil painting, but the other is vitrification. Leonardo is known to have spent a great deal of time in experiments, of which this is a specimen, and it may appear ridiculous to the practitioners of more modern date, as he does not enter more fully into a minute description of the materials, or the mode of employing them. The principle laid down in the text appears to me to be simply this: to make the oil entirely evaporate from the colours by the action of fire, and afterwards to prevent the action of the air by the means of a glass, which in itself is an excellent principle, but not applicable, any more than enamel painting to large works.