from this condition, who complained of severe pain in the urinary passage as I was introducing the sound, and I recognized that there were wounds in the same part, for as soon as these were touched by the sound the urine began to flow, followed soon after by a little blood and fleshy particles.... So far as the operation of physicians is concerned, it is necessary only to be certain of the fact that obstruction to the passage of urine depends upon no other cause than stone or the presence of coagulated blood (f. 271). Gilbert's medical treatment of vesical calculus consists generally in the administration of diuretics and lithontriptics and the local application of poultices, plasters and inunctions of various kinds. Of the lithontriptics, certain combinations, characterized by famous names or notable historical origin, are evident favorites. Among this class we read of the _Philoantropos major_ and _minor_, the _Justinum_, the _Usina_ "approved by many wise men of Babylon and Constantinople," the _Lithontripon_ and the "_Pulvis Eugenii pape_," with numerous others. Rather curiously and suggestively no mention is made in this immediate connection of the technique of lithotomy. On a later page, however (f. 309a), we find a chapter entitled "_De cura lapidis per cyrurgiam_," in which Gilbert writes: "Mark here a chapter on the cure of stone in the bladder by means of surgery, which we have omitted above. Accordingly, to determine whether a stone exists in the bladder, let the patient take a warm bath. Then let him be placed with his buttocks elevated, and, having inserted into the anus two fingers of the right hand, press the fist of the left hand deeply above the pubes and lift and draw the entire bladder upward. If you find anything hard and heavy, it is manifest that there is a stone in the bladder. If the body feels soft and fleshy, it is a fleshy excrescence (_carnositas_), which impedes the flow of urine. Now, if the stone is located in the neck of the bladder and you wish to force it to the fundus: after the use of fomentations and inunctions, inject through a syringe (_siringa_) some petroleum, and after a short interval pass the syringe again up to the neck of the bladder and cautiously and gently push the stone away from the neck to the fundus. Or, which is safer and better, having used the preceding fomentations and inunctions, and having assured yourself that there is a stone in the bladder, introduce your fingers into the anus and compress the neck of the bladder with the fist of the left hand above the pubes, and cautiously remove the stone and guide it to the fundus. But if you wish to extract the stone, let a spare diet precede the operation, and let the patient lie abed for a couple of days with very little food. On the third day introduce the fingers into the anus as before, and draw down the stone into the neck of the bladder. Then make your incision lengthwise in the fontanel, the