Sometimes calculi occur in the bladder, sometimes in one kidney and occasionally in both kidneys. The symptoms produced by their presence vary in accordance with the situation of the concretion. If the stone is in the kidney, the foot of the side affected is numb (_stupidus_), the spine on the affected side is sore and there is difficulty of micturition and considerable gravelly sediment in the urine. If the stone is increasing in size, the quantity of sediment also increases, but if the stone is fully formed and confirmed, the amount of sediment decreases daily, and the urine becomes milky both in the kidneys and the bladder. A stone in the bladder occasions very similar symptoms, together with pain in the peritoneum and pubes, dysuria and strangury, and sometimes the appearance of blood and flocculi (_trumbos_?) in the urine. Patients suffering from vesical calculus are always constipated, and the dysuria may increase to the degree called furia, a condition not without some danger. Three things are necessary in the cure of stone, viz., a spare and simple diet, the use of diuretics and a moderate amount of exercise. It should, however, be remarked that confirmed stone is rarely or never cured, except by a surgical operation.... If a boy has a clear and watery urine after it has been sandy, if he frequently scratches his foot, has involuntary erections and finally obstruction in micturition, I say that he has a stone in the neck of his bladder. If now he be laid upon his back with his feet well elevated, and his whole body be well shaken, if there is a stone present it is possible that it may fall to the fundus of the bladder. Afterwards direct the boy to bear down (_ut exprimat se_) and try to make water. If this treatment turns out in accordance with your theory, the urine necessarily escapes and your idea and treatment are confirmed. If, however, the urine not escape, let the boy be shaken vigorously a second time. If this too fails and strangury ensues, it will be necessary to resort to the use of a sound or catheter (_argaliam_), so that when the stone is pushed away from the neck of the bladder the passage may be opened and the urine may flow out. It may be possible too that no stone exists, but the urethra is obstructed or closed by pure coagulated blood. Perhaps there may have been a wound of the bladder, although no external haemorrhage has appeared, but the blood coagulating gradually in the bladder has occasioned an obstruction or narrowing of the urinary passage. Or possibly the blood from a renal haemorrhage has descended into the bladder and obstructs the urethra. Hence I say that the sound is useful in these cases where the urethra is obstructed by blood or gross humors. Examination should also be made as to whether a fleshy body exists in the bladder, as the result of some wound. This condition is manifest if, on the introduction of the sound, the urine flows out promptly. I once saw a man suffering