_In the air passages._--Should the foreign body lodge _over the entrance of or in the larynx_ the patient will be seized with a violent fit of coughing which may expel it; but, should this not happen, symptoms of asphyxia will supervene. With regard to treatment; the head should immediately be brought forward and the finger inserted along the side of the mouth into the pharynx, and then given a forward sweeping movement; by this means the foreign body, if lodged at the back of the tongue, will probably be removed. This failing, the patient must if possible be inverted and a forcible slap given on the back. If the foreign body is not dislodged by this method, laryngotomy should be immediately performed. There must be no hesitation about the performance of this operation and it must be carried out promptly, for the longer it is delayed the less becomes the chance of saving the life of the patient. _A foreign body in the trachea or bronchus_ may give rise to no immediate symptoms, but generally a violent fit of coughing, with signs of impending asphyxia, takes place at the time of the accident. These signs pass away, to be followed at intervals by fresh attacks of coughing and eventually by symptoms of collapse of the lung or lungs. In a case recorded by Sir William MacCormac,[22] during the removal of an upper bicuspid the palatine blade of the forceps snapped off close to the joint and disappeared. The patient immediately suffered from great dyspnœa and appeared to be dying. The symptoms passed away, and for the following six weeks the patient’s condition gave no great cause for anxiety, although she suffered from a constant hacking cough accompanied by bloody expectoration. Seven weeks after the accident she was admitted into St. Thomas’s Hospital, the foreign body was with difficulty removed from the right bronchus, and the patient made an excellent recovery. _The diagnosis of a foreign body in one bronchus_ is made by an absence of signs of respiration over the whole or part of the lung on that side, with exaggerated sounds (puerile breathing) over the opposite side. Treatment consists in performing tracheotomy and removing the foreign body. _In the food passages._--_A foreign body impacted in the pharynx_ will give rise to pain, symptoms of dysphagia and dyspnœa. A hacking cough is generally present. Should a foreign body be suspected in the pharynx, its presence can usually be ascertained by digital exploration; this failing, the cavity should be examined by the aid of a laryngoscope. An attempt should first be made to remove the body with the fingers, and if this is unsuccessful pharyngeal forceps must be called into use. In some cases where the impaction is very firm it may be necessary to perform pharyngotomy.