_A Silver Catheter_ is passed most easily while the patient is in a horizontal position, with the shoulders low and the thighs separated. The surgeon stands on the left side of the patient, and holds the catheter, previously warmed and lubricated with oil or lard, lightly between the thumb and two first fingers of the right hand, the beak downwards and the stem across the patient’s left groin. Then taking the penis between the middle and ring fingers of the left hand, the palm being upwards, he pushes back the foreskin with the thumb and forefinger, and steadies the meatus while introducing the beak of the catheter. This done, he draws the penis gently along the catheter as the point is lowered to the perinæum, but without raising his right wrist until the instrument has travelled 5 or 6 inches along the passage and reached the triangular ligament. The surgeon then carries his right wrist to the middle line of the patient’s body, and while pushing the point onwards, raises the hand round a curve till it again sinks between the patient’s thighs. When the bladder is reached he withdraws the stylet that the urine may escape. Three points of difficulty are usual in passing catheters; the lacuna magna just within the meatus, the triangular ligament, and the prostatic part of the urethra just before the bladder is reached. The first is escaped by keeping the beak along the floor of the urethra for the first two inches; the second is best avoided by raising the wrist as the instrument passes the triangular ligament, and directing the beak against the upper surface of the urethra, lest, being in the enlarged bulbous part, it sink below the opening in the ligament; the third difficulty is overcome by depressing the hand well as the point approaches the bladder. _To pass the catheter in the upright position_, the patient is placed against a wall or firm object, with his heels eight or ten inches apart and five from the wall, that he may rest easily during the operation. The surgeon sets himself opposite the patient and grasps the penis with the two middle fingers of the left hand, the palm upwards; he next exposes the meatus with the thumb and forefinger, and his right hand holding the catheter by its middle obliquely across the left side of the patient, he draws the penis on to the instrument till the triangular ligament is gained. He then carries the shaft of the catheter to the middle line and, holding it by its end, brings the right hand downwards and forwards, to carry the point upwards over the obstruction at the neck of the bladder.