Black varnish for sword guards, metal bands for chests, etc.

Take linseed oil or, for a cheaper option, walnut oil, and rid it of fat with garlic cloves and hog’s fennel (some also add bread crusts), which you will boil in it for a good quarter of an hour. Then add to one pound of the oil boiled in this way a piece of black pitch the size of a walnut and a double handful of wheat, without removing the garlic and onions, and allow to boil together for a good quarter of an hour. Once the pitch is well melted and the oil takes on body, you can remove it from the fire. Then, to varnish, place your iron over a warm charcoal fire and apply with a feather or a brush. When you see that it no longer smokes, it is done and your varnish is dry.

at left top margin of folio 004v

For an excellent black varnish, add two or three paternoster beads to the rest.

at left top margin of folio 004v

Some consider walnut oil to be better.

at left top margin of folio 004v

If there is a quantity of varnish, it needs to boil for at least half a day, because the more it boils, the better it is. Should the varnish boil over, it is dangerous for it to catch fire and it is difficult to extinguish. So do this in a courtyard or other open space.

at left middle margin of folio 004v

In five or six lbs. of oil, one must put one lb. of galipot, which costs 4 sols, and some peeled garlic cloves. This varnish is not black in and of itself, but turns black when exposed to fire.

at left middle margin of folio 004v

See below, around the 3rd part of this book, after sands, in the chapter on furbishers.