"Bloodletting Man” from Feldtbůch der Wundartzney by Hans von Gersdorff, 1528
Sites for Bloodletting
Until early modern times, much medical theory and practice hinged on the notion that health required a balance of the four humors in the body. It was believed that the volume of blood, one of the primary humors, needed to be kept in check, either by natural bleeding or by the human intervention of “bloodletting.” This was done by the application of leeches and, far more commonly, by phlebotomy or venesection, that is, a small incision in a vein. As physicians delegated this procedure to surgeons and barbers, who were less knowledgeable about anatomy, it became increasingly important to have “maps” of the veins to be incised for specific purposes.