_Esophageal Dilators_.--The dilatation of cicatricial stenosis of the esophagus can be done safely only by endoscopic methods. Blind esophageal bouginage is highly dangerous, for the lumen of the stricture is usually eccentric and the bougie is therefore apt to perforate the wall rather than find the small opening. Often there is present a pouching of the esophagus above a stricture, in which the bougie may lodge and perforate. Bougies should be introduced under visual guidance through the esophagoscope, which is so placed that the lumen of the stricture is in the center of the endoscopic field. The author's endoscopic bougies (Fig. 40) are made with a flexible silk-woven tip securely fastened to a steel shaft. This shaft lends rigidity to the instrument sufficient to permit its accurate placement, and its small size permits the eye to keep the silk-woven tip in view. These endoscopic bougies are made in sizes from 8 to 40, French scale. The larger sizes are used especially for the dilatation of laryngeal and tracheal stenoses. For the latter work it is essential that the bougies be inspected carefully before they are used, for should a defective tip come off while in the lower air passages a difficult foreign body problem would be created. Soft-rubber retrograde dilators to be drawn upward from the stomach by a swallowed string are useful in gastrostomized cases (Fig. 35). [FIG 38.--Half curved hook, 45 cm. and 60 cm. Full curved patterns are made but caution is necessary to avoid them becoming anchored in the bronchi. Spiral forms avoid this. The author makes for himself steel probe-pointed rods out of which he bends hooks of any desired shape. The rod is held in a pin-vise to facilitate bending of the point, after heating in an alcohol or bunsen flame.] _Hooks_.--No hook greater than a right angle should be used through endoscopic tubes; for should it become caught in some of the smaller bronchi its extraction might result in serious trauma. The half curved hook shown in Fig. 38 is the safest type; better still, a spiral twist to the hook will add to its uses, and by reversing the turning motion it may be "unscrewed" out if it becomes caught. Hooks may easily be made from rods of malleable steel by heating the end in a spirit lamp and shaping the curve as desired by means of a pin-vise and pliers. About 2 cm. of the proximal end of the rod should be bent in exactly the opposite direction from that of the hook so as to form a handle which will tell the position of the hook by touch as well as by sight. Coil-spring hooks for the upper-lobe-bronchus (Fig. 39) will reach around the corner into the ascending bronchus of the upper-lobe-bronchus, but the utmost skill and care are required to make their use justifiable. [FIG. 39.--Author's coil-spring hook for the upper-lobe, bronchus]