LIV. Callot's varnish, mentioned in Chap. 1. p. 2.

Valuable Secrets concerning Arts and Trades:
or Approved Directions, from the best Artists, for the Various Methods...
Printed by Thomas Hubbard,
Norwich, 1795Chap. III. Secrets for the composition of Varnishes, &c.


1. Take two ounces of the finest lintseed-oil; benjamin, in drops, two drachms; virgin-wax, the bulk of a filbert. Boil all this together, till it is reduced to one third; and, while it is a-boiling, never cease to stir with a little stick. When done, bottle, or pot it in a large-mouthed vessel.

2. To use that varnish, warm a little the plate you intend to engrave upon; and, taking a little of the varnish with the tip of your finger, spread it delicately over the plate. Observe to put as little of it as you can, and to lay it on as smooth and equal as possible. When done, smoak the plate, on the varnish side, with a candle, passing and repassing it gently, over the flame of it, till it is black every where. Set it again, now, on the chaffingdish, wherein there are kindled charcoals; and, when the plate has done fuming, then the varnish is sufficiently hardened. You may then chalk, draw, and etch, whatever you will on it.

Such is the true receipt of the varnish, which the famous Callot made use of, to engrave his most admired, and truly admirable, subjects.