Mercurial Ointment.
Take of quicksilver, two ounces; hogs' lard, three ounces; mutton suet, one ounce. Rub the quicksilver with an ounce of the hogs's lard in a warm mortar, till the globules be perfectly extinguished; then rub it up with the rest of the lard and suet, previously melted together.
The principal intention of this ointment is to convey mercury into the body by being rubbed upon the skin.
William Buchan
Domestic Medicine 2nd edition 1785