The Esophagus is normally about 1o inches long and 1/2 inch wide, and presents two constrictions, one at the beginning, and the other at the point where it is crossed by the left bronchus, each capable of admitting an instrument 4/5 inch in diameter. Foreign bodies are most apt to lodge at these points. But for the pylorus, it is the narrowest and one of the most muscular portions of the alimentary tract. It extends from the termination of the pharynx, opposite the sixth cervical vertebra, to the cardiac orifice of the stomach, opposite the eleventh dorsal vertebra ; presents an anteroposterior curve in conformity with the vertebral curve, and also two lateral curves to the left, the first at the lower portion of the neck and upper portion of the thorax, and the second behind the pericardium, where it also passes forwards to reach the oesophageal opening in the diaphragm. In addition to the portion in the neck, thoracic, diaphragmatic, and abdominal portions are described.

In the thorax it lies close to the vertebral column in the superior mediastinum, while in the posterior mediastinum it comes forward into contact with the posterior surface of the pericardium. The trachea and left bronchus also lie in front. Behind lie the longus colli muscle and vertebral column above, while below the vena azygos major, thoracic duct, and aorta intervene between the oesophagus and column. On the left side the thoracic duct, pleura, and left subclavian artery lie super'iorly, then the aorta, and again the pleura. On the right side lie the arch of the azygos vein and pleura. The pneumogastrz'c nerves form with the sympathetic the oesophageal plexus (plexus gulae), and then pass to the stomach along with the oesophagus, the left nerve lying in front, and the right behind.

The oesophagus passes through the diaphragm very obliquely, and laterally and posteriorly is in contact with the walls of the orifice for a distance of inch. The abdominal portion is possibly inch in length.

Dysphagia, or difficulty in swallowing, may be due to (1) spasmodic stricture (oesophagismus) ; (2) organic stricture, which may be fibrous (resulting perhaps from swallowing a corrosive, and situated generally at the upper part of the tube, or due to syphilis, etc.), or may be carcinomatous ; (3) pressure on the oesophagus from without, as by a tumour or aneurism ; (4) impaction of a foreign body.

In order to ascertain the condition of the oesophagus in such conditions, a stethoscope may be placed over the back, and the patient asked to swallow. Normally the act of swallowing is almost silent, whereas in stricture a sound of dripping, as succeeding drops pass the stricture, is frequently audible.

An oesophageal bougie is frequently passed, care being taken before doing so to exclude the possibility of aneurism, which might otherwise be ruptured. In passing the bougie the head should be flexed forwards, and not thrown backwards, so as to prevent the bougie from entering the larynx, and the point guided by the finger past the back of the throat. False passages may be formed if sufficient gentleness be not exercised. While it is possible to attack the oesophagus in the thorax from the back, portions of ribs being resected, and the pleura carefully avoided, it is generally desirable in cases of oesophageal stricture to alleviate the condition by performing a gastrostomy.