To Kill A Canker

Take 2 spoonfulls of honey and one spoonfull of treacle and half as much rock allum as the quantity of a wallnut beat to fine powder and boyle these together over a cheafen dish of coles till it be pretty thick then take it off and let it coole then anoint the cankers with a cloth tyed upon a stick the oftner you anoint it the better twill be you must keep stiring it as long as it doth boyle, it will be like a sirrup when tis cold.

Source: A Book of Simples, H.W. Lewer