In his memoirs, Stabsfunkmeister (Chief Petty Officer Radio) Hirschfeld describes treating boils, a common afflication aboard U-Boats, with ichthyol, a topical ointment distilled from shale oil. While not curing the boils, it softened the skin around them and allowed them to come to a head more quickly so they could be lanced.
Charles McCain is a Washington DC based freelance journalist and novelist. He is the author of "An Honorable German," a World War Two naval epic. You can read more of his work on his website: http://charlesmccain.com/ View all posts by Charles McCain