The passage of the catheter is in some cases one of the most delicate operations in surgery, but when a gum elas tic instrument is used, and the instrument is allowed to follow the course of the canal without the application of any very great degree of force, it may generally be accomplished with ease, even by the patient himself. Every person who is at times dependent upon a catheter, should learn the art of using it properly from a skillful surgeon. The passage of the instrument in females is a very simple operation.

Fig. 501. Catheter.

Fig. 501. Catheter.