I have said that, on some occasions, the rupture of the capsule, being too narrow to admit the head of the humerus to repass it, and return to its cavity, constitutes one of the principal obstacles to a reduction (24). To enlarge this passage, by further lacerating its edges, is evidently the indication that here presents itself. This is fulfilled by communicating to the bone great motion, either by circumduction, or rotation on its own axis, forcing it suddenly in different directions, particularly in that direction in which the luxation has been produced. Its superior extremity must be, at the same time, pushed forcibly against the ruptured capsule, which, by being thus pressed between two resisting bodies, will suffer a more extensive rupture. Reduction, oftentimes impracticable previously to these violent and varied motions, takes place of itself as soon as they have been properly made. Of this the practice of Desault furnishes many examples. CASE VIII. In the Journal of Surgery are recorded two cases, one by Anthaume, the other by Faucheron, which establish this doctrine. John Seligni, a robust man, forty-four years of age, fell on the point of his shoulder, on the 19th of July 1791; the pain, which was increased by moving his arm, and the swelling which supervened almost immediately, induced him to enter the Hotel-Dieu. The efforts of assistants were at first insufficient, and it was not till after a uniform extension continued for several minutes, that the head of the humerus was drawn by the muscles against the glenoid cavity. The bone appeared to enter the cavity, although the persons present did not hear the collision or clashing of the articulating surfaces, which is almost always perceived in cases of recent luxation: but immediately the humerus was again displaced, without its being practicable to retain it. On the occurrence of this phenomenon, Desault conceived that the head of the bone had pushed before it the capsular ligament, through which it could not pass, in consequence of the narrowness of the opening which had been made at the time of the luxation. He proceeded to move the arm forcibly in every direction, in order to enlarge the opening, and immediately felt a kind of laceration, which satisfied him that his views were accomplished. He then re-commenced extension, which it was again necessary to continue, as at first, for some time, in order to overcome the resistance of the muscles. The reduction was attended with no further difficulty. The humerus continued still to have a great tendency to be displaced, and it was necessary to employ, for several days, a bandage similar to that for a fractured clavicle.