Another Way
Reduce gum ammoniac into powder, and dissolve it in gum arabic water,
to which a little garlic juice has been added. This water will not
dissolve the ammonia so as to form a transparent liquid; for the
result will be a milky liquor. With the liquor form your letters or
ornaments on paper or vellum, with a pen or fine camels'-hair brush;
then let them dry, and afterwards breathe on them some time, till they
become moist; then apply a few bits of leaf gold to the letters, which
you press down gently with cotton wool. When the whole is dry, brush
off the superfluous gold with a large camels'-hair brush, and, to make
it more brilliant, burnish with a dog's tooth.