4. =Of the Eye.=--The iris may be injured by sharp blows, as from the cork of a soda-water bottle. It is usually followed by haemorrhage into the anterior chamber, and there may be separation of the iris from its ciliary border. Wounds at the edge of the cornea are often followed by prolapse of the iris. Acute traumatic iritis or irido-cyclitis may supervene four or five days after the injury. The lens is frequently wounded in addition to the cornea and iris. In dislocation of the lens into the anterior chamber as the result of a blow, the lens appears like a large drop of oil lying at the back of the cornea, the margin exhibiting a brilliant yellow reflex. Partial dislocations of the lens as the result of severe blows generally terminate in cataract. 5. =Of the Throat.=--Very frequently inflicted by suicides. Division of the carotid artery is fatal, and of the internal jugular vein very dangerous on account of entrance of air. Wounds of the larynx and trachea are not necessarily or immediately dangerous, but septic pneumonia is very apt to follow. Wounds of the throat inflicted by suicides are commonly situated at the upper part, involving the hyoid bone and the thyroid and cricoid cartilages. The larynx is opened, but the large vessels often escape. In most suicidal wounds of the throat the direction is from left to right, the incision being slightly inclined from above downwards. At the termination of a suicidal cut-throat the skin is the last structure divided, the wound being shallower as it reaches its termination; the wounds often show parallelism. The weapon is often firmly grasped in the hand. Inquiry should be made as to whether the patient is right or left handed, or ambidextrous. Homicidal cut throat is usually very severe and situated low down in the neck or far to the side. 6. =Of the Chest.=--Incised wounds of the walls are not of necessity dangerous; but severe blows, by causing fracture of the bones and internal injuries, are often fatal. The symptoms of penetrating wounds of the chest are--(1) The passage of blood and air through the wound; (2) haemoptysis; (3) pneumothorax; and (4) protrusion of the lung forming a tumour covered with pleura. Fracture of the ribs may be due to direct violence, as from a blow, when the ends are driven inwards, or to indirect violence, as from a squeeze in a crowd, when the ends are driven outwards. 7. =Of the Lungs.=--These usually cause haemorrhage, and are frequently followed by pleurisy, either dry or with effusion, and by pneumonia. 8. =Of the Heart.=--Penetrating wounds are fatal from haemorrhage, of the base more speedily than of the apex; but life may be prolonged for some time even after a severe wound to the heart. Injury to the right ventricle is the most fatal injury and the most frequent. Rupture from disease usually occurs in the left ventricle; rupture from a crush is usually towards the base and on the right side. 9. =Of the Aorta and Pulmonary Artery.=--Fatal.