False passages will occur sometimes in spite of at least ordinary care, and are always serious in their nature. Extravasation of urine may result, with more or less disastrous consequences, or speedy septic infection may quickly terminate the life of the individual. They are to be avoided, as far as possible, by the use of instruments of large rather than of small size, with blunt tips, and by delicacy of manipulation. For this purpose it is well to avoid the use of catheters which require a wire stylet for the maintenance of their proper curve, lest during manipulation the point of the wire may work injury. The various accidents due to or connected with catheterization will be dealt with in their proper places in connection with the surgery of the urethra and bladder. There are certain constitutional complications, however, which deserve mention. One of these is known as _urethral fever_, which comes on usually with a chill, followed by more or less rise in temperature, and with general disturbance of the system. It is to be regarded as a manifestation of septic intoxication, the hope being that the disturbance may not go beyond this degree. In cases that have once suffered from this intoxication precautions should be doubled. The deep urethra should be irrigated before and after the withdrawal of the urine, the patient should be kept in bed, and urotropin and quinine may be administered before and after the discharge of urine. Much may be done in the prevention of this as of other unpleasant occurrences, such as pain, excitement, suppression of urine, syncope, etc., by the previous use of cocaine and by due regard for gentleness. Should a septic process be set up in the deep urethra it may lead to sapremia of urethral origin, and to septicemia and pyemia. Septic complications accompanied by any local indications, such as swelling, should make the surgeon watchful for the time when an incision must be made for relief of tension or escape of pus. Postoperative suppression of urine, which may occur even after catheterization, may be treated by giving 0.08 to 0.15 Cg. of sulphate of sparteine every three or four hours (McGuire). SKIN GRAFTING.