This section is from the book "The Home Hand-Book of Domestic Hygiene and Rational Medicine. Volume 2.", by J. H. Kellogg, M.D.. Also available from Amazon: The Home Hand-Book of Domestic Hygiene and Rational Medicine, Volume 2.
This is a thickened condition of the epidermis or scarfskin. It is most likely to occur over joints and the prominent points of bones. It is generally produced by prolonged pressure. Its object is the protection of the sensitive parts beneath from injury. A callus does not usually require treatment except when the part becomes inflamed. The proper treatment is soaking in very hot water for fifteen or twenty minutes three or four times a day, and the wearing of a poultice or wet compress the balance of the time.