Fat oil: Put linseed oil into leaden vessels, made in the form of dripping pans, so much as to be an inch deep; expose them to the sun for six months, till it becomes as thick as turpentine; the longer it stands the fatter it will be, and give gold a greater gloss. It is almost as thick as butter, so as you may in a manner cut it with a knife, it is excellent, and ought to be carefully kept for use.