A stele of the physician Jason of Athens with the text: "Jason, also known as Decimus, of the Archarnian deme", Jason examines a child, with an unnaturally enlarged stomach. To the right a cupping vessel is shown (scale exaggerated) which when heated is used to draw blood or pus from a wound. Cupping, an ancient therapy was used until the 19th century assumed to restore the balance of the body's humours. The vessel when heated created a partial vacuum that made it stick to the body surface by suction. This raised a weal on the skin (dry cupping) or drew out blood (wet cupping) if it was set over cuts.