The other method is by abdominal incision or laparotomy, which is usually made through the linea alba, though in a number of cases the outer edge of the rectus abdominis on the side corresponding to the organ to be removed has been taken as the guide. The steps of the operation are similar to those of ovariotomy where the pedicle is tied and returned to the abdominal cavity. This operation may be one of choice, from the greater ease with which the pedicle can be reached and the possibility of increasing the length of the incision in case of necessity for the removal of a very large tumor. In one case a crucial incision was made. When the kidney to be removed is a wandering one, and especially when a kidney has become fixed in an anomalous position, this is by far the easiest, and sometimes the only practicable, method. Antiseptic precautions are of course to be used. Hydro-nephrosis. Obstruction to the discharge of urine from the body naturally produces special disorders in the secreting and discharging organs. If the obstruction exist below the neck of the bladder, as in stricture of the urethra or enlarged prostate, then the bladder is the organ primarily affected, and it may become distended, sacculated, its muscular coat hypertrophied, its mucous membrane affected with catarrhal inflammation, and its contents changed from the normal by the addition of mucus, of pus, of bacteria, or a deposit of earthy phosphates from the ammoniacal reaction produced by decomposition of the urea. The effects of distension of the bladder will sooner or later make themselves felt in the upper urinary passages, and will then give rise to the same dilatation of the ureters and the renal pelvis as occurs when the {57} obstruction is higher up. As regards the rapidity with which such changes progress, much depends upon the degree of obstruction as well as upon the amount of urine secreted. It probably, however, never takes place suddenly. In a case which came under the observation of the writer a partial paralysis of the bladder, probably existing from infancy, had in the course of three or four years, during which large quantities of light urine were passed, given rise to dilatation of the ureters, slight dilatation of the pelvis of the kidneys, atrophy of the parenchyma, and hypertrophy of the left ventricle.