Dictionarium polygraphicum. To discover white upon black with an iron pencil.

Dictionarium Polygraphicum:
Or, The Whole Body of Arts Regularly Digested.
Vol II.
London: Printed for C. Hitch and C. Davis in Pater-noster Row, and S. Austen in St. Paul's Church Yard. MDCCXXXV.
1735
Having well cover'd your frame or other piece of work with a white ground, well varnish'd, polish'd and rush'd; take lamp black, and having ground it with yolk of egg, make trial of it apart, to see whether the black, when fixt, will burnish very bright. You must size your black as much as it is necessary to make it stick.

Colour your frame, &c. with this black, lay it on well, dry it, and burnish it with a tooth; then take an awl or bodkin of iron, sharpened and flatted at the end like a chizel, of such breadth you would have your fillet to be, and with a ruler and this iron thus sharpen'd, draw fillets, scraping off the black, till you come to the white.

You may also, if you please, with a bodkin make Moresk works, which you may hatch into every leaf; as also other branch'd works, the imbossment of which, you may make by scraping off the black with an iron bodkin, till you can see the white, still keeping your iron-tool sharp and smooth.

By this means your work will be of a fine black, well burnish'd or polish'd like marble, in which you will have branch'd works that will seem like ivory inlaid in wood.

If your figures appear too much shadow'd, after you have drawn out all your work with a bodkin, take one or more irons like a folding-stick or rather blunter, as you shall see convenient; let it be well smooth'd and harden'd, and with it rub the figures as evenly as is possible, till no black appears any longer; but not suffering the iron to enter any farther than the superficies of the whites that is, when the black shall be rubb'd off, and the figure shall appear very white and smooth; and afterwards with a tooth burnish the white you have laid bare: and lastly with a small pencil, you shall draw the lines and hatch the shades, as if it were horn engraven or carv'd.