In like manner, al-Zahrāwī discusses cautery of the stomach and the "cold liver" in chapters 26 and 27, respectively. The drawings therein represent shapes of the burns on the skin (fig. 4) and marks of ink to be drawn beneath the cartilage of the ribs (fig. 5) for the purpose of spotting the area of operation. Here also he describes carefully and clearly the methods of applying cautery and the types, position, and number of tools employed in each case. He likewise depicts (in chapter 45) instruments used in the treatment of hernia (fig. 6). The second section (bāb), with about 99 chapters,[20] deals with incision, puncturing, venesection, cupping, surgery on abscesses, and the withdrawal of arrows from the body. Al-Zahrāwī warns that ignorance in such operations may lead to damage of an artery or vein, causing loss of blood "by which life is sustained."[21] Moreover, needle and thread (more than one kind is mentioned) for the stitching of wounds are repeatedly recommended. According to al-Zahrāwī, foreign bodies that lodge in the ear (chapter 6) are of four origins: (1) "mineral stones" or substances resembling mineral stones such as iron and glass; (2) plant seeds (chick-peas and beans); (3) liquids, such as water and vinegar; and (4) animals, such as fleas. Several instruments are recommended for the removal of such foreign bodies--fine tweezers shaped like a dropper (fig. 7), a syringe with plunger-pump, and a tube made of silver or copper (fig. 8). Also of interest to pharmacy and therapy is the advice in regard to the use of lubricants to be applied before administering these fine instruments into the body’s cavities. Chapter 24 is concerned with the treatment of the polypus that grows in the nose. The various kinds (including cancer growth), shapes, and colors of this type tumor and its treatment by surgery or medicine are described. A hollowed nose-dropper made of metal in the shape of a small kerosene lamp[22] is suggested (fig. 9). The dropper is held by its handle while its contents are heated before use. Applying heat to nose drops was probably proposed because it serves two purposes: it allows easier flow of the "duhn," or the fatty substance used, and it raises the temperature of the drops to that of the body. In his discussion on dental hygiene,[23] al-Zahrāwī describes scrapers and dental forceps for teeth cleaning and extraction (figs. 10, 11) and brings in a few points of historical interest.[24] He warns of the common error of extracting the adjacent healthy tooth instead of the ailing one due to the patient’s sense deception. For a gargle he prescribes salt water, vinegar, and wine (sharāb). To stop hemorrhage he used blue vitriol (al-zāj)--copper sulfate in our modern terminology.