Creating Waves of Awareness
A small boil or foruncle on the skin troubles a lot. At an inconvenient location it is more troublesome. How does a small boil on the skin look like? It is raised, it is red, it is painful and it is hot.
If heat in the form of fomentation is applied on the healthy skin, the skin becomes raised, red, painful and hot.
So in the earliest stage of a boil on the skin repeated fomentations offer what amounts to a cure. Capsicum or oil of wintergreen application does the same but may irritate the skin and even may ulcerate.
This is one more example of the principle of "similibia etc"