Dissolve a couple of drachms of lunar caustic, and half an ounce of gum
arabic, in a gill of rain water. Dip whatever is to be marked in strong
pearl-ash water. When perfectly dry, iron it very smooth; the pearl-ash
water turns it a dark color, but washing will efface it. After marking
the linen, put it near a fire, or in the sun, to dry. Red ink, for
marking linen, is made by mixing and reducing to a fine powder half an
ounce of vermilion, a drachm of the salt of steel, and linseed oil to
render it of the consistency of black durable ink.