The woman is placed on the table in the lithotomy position, and the bladder is emptied with the catheter. The external meatus is then dilated to the requisite size by inserting the graduated calibrator with a general rotary movement. When the meatus has been stretched sufficiently, as indicated by the number on the calibrator (usually about 12 millimeters), the instrument is withdrawn, and the speculum of corresponding number, armed with the obturator, is introduced; the obturator is then removed. The hips of the woman are now elevated on the pillows or the inclined plane, or the foot of the table is raised, so that the hips shall be from 10 to 20 inches above the level of the shoulders. The examiner, armed with the head-mirror or light, is then prepared to inspect the interior of the bladder. If the mirror is used, the light (Argand burner or electric drop-light) should be held close to the pubis of the patient. [Illustration: FIG. 187.--Vesical probe or applicator.] Usually a small quantity of urine remains in the bladder after catheterization, or is secreted during the preliminary procedures, and it is necessary to remove this before complete examination of the bladder can be made. This may be done by means of the small balls of absorbent cotton or the strips of gauze grasped with the long-toothed forceps and passed in through the speculum; or some form of suction apparatus may be employed, consisting of a rubber exhaust bulb and a long metal tube perforated at the distal end by small openings. The elevated position of the hips is an essential part of this method of examination; it permits the intestines to gravitate out of the pelvis, and, as soon as the urethra is opened, the bladder becomes distended with air, so that all of its interior may be readily inspected, and applications to the surface may be directly made through the speculum. In some cases it is difficult to produce the requisite distention of the bladder by elevating the hips. This difficulty may arise in the case of very fat women. It then becomes necessary to place the patient in the knee-chest position, when the requisite distention is readily accomplished. As the speculum is withdrawn from the bladder the internal meatus and the urethral walls may be examined as they fall together beyond the distal end of the instrument. DISEASES OF THE URETHRA. The female urethra is a musculo-membranous canal averaging 1¾ inches in length, and, when not stretched, about ¼ inch in diameter. The urethra is normally closed by the apposition of its walls. In the neighborhood of the external meatus it is an antero-posterior slit. In the neighborhood of the internal meatus it is a transverse slit. In the middle portion the mucous membrane is arranged in longitudinal folds, and a transverse section shows a stellate closure. The muscular coat of the urethra contains both striped and unstriped muscular fibers.