THYROTOMY is an operation by which the larynx is opened in the middle line by a vertical incision, and its halves separated, while any morbid growths are excised from the cords or ventricles. The merits and dangers of this operation have been discussed at length by Mr. Durham[135] and Dr. Morell Mackenzie.[136] LARYNGECTOMY OR EXCISION OF THE LARYNX, first performed by Dr. Heron Watson in 1866, has been lately frequently performed for carcinoma and sarcoma. Each case presents its own difficulties, which vary according to the amount and extent of the disease for which it is done. The trachea must be divided and tamponed by a Trendelenburg canula, after which the larynx must be carefully dissected out. The immediate mortality, _i.e._ in first ten days, is fifty per cent., and Dr. Gross holds that life has not been prolonged by the operation.[137] OESOPHAGOTOMY.--This operation is very rarely required, and has as yet been performed only for the removal of foreign bodies impacted in the oesophagus, and interfering with respiration and deglutition. To cut upon the flaccid empty oesophagus in the living body would be an extremely difficult and dangerous operation, from the manner in which it lies concealed behind the larynx, and in close contact with the great vessels. When it is distended by a foreign body, and specially if the foreign body has well-marked angles, the operation is not nearly so difficult. It has now been performed in forty-three cases at least, of which eight or nine have proved fatal. Seven, along with another in which he himself performed it with success, were recorded by Mr. Cock of Guy's Hospital.[138] Three others were performed by Mr. Syme, with a successful result. Of the seven cases collected by Mr. Cock only two died, one of pneumonia, the other of gangrene of the pharynx.