This paper considers, briefly: 1, why surgeons splint a broken leg; 2, the plaster-of-paris treatment for it; and 3, a new leg-splint devised by the writer. <h3>WHY SHOULD SURGEONS SPLINT A BROKEN LEG?</h3> The question, though elementary, is quite opportune, as shall be shown further on. Senn<sup>1</sup>says: "In the treatment of fractures as in the treatment of wounds of the soft parts accurate coaptation and effective fixation should be aimed at, so as to place the parts in the most favorable conditions to unite by the smallest possible amount of new material." Thomas Bryant,<sup>2</sup>in his manual, writes: "After the setting of the fracture, the essential part to be observed in its treatment is the immobility of the broken bone; and next to this, its exposure during the process of repair to render certain that the bone has maintained its right position." These quotations are sufficient to answer