(106.) _To stop Bleeding._ Bleeding will, if no large arteries are divided, cease on the free exposure of the surface for a few minutes to the air; but when a large vessel has been cut, more determined means must be had recourse to. Pressure on the bleeding surface and its neighbourhood will in many cases succeed, but this or any similar method is far inferior to that of securing the open vessel by a thread. To accomplish this, the mouth of the vein or artery must be slightly drawn out from the contiguous surface, by means of a small hook, called by surgeons a tenaculum, and easily procured from any blacksmith. While the mouth of the vessel is thus held exposed, an assistant must surround it with a noose of thread, which, on being secured with a double knot, will effectually close it. The thread ought to be of white silk, though any undyed thread, which is firm, round, and capable of standing a pull, will answer the purpose. Care must be taken to place the thread, before tying it, fairly behind the point of the tenaculum, so as to avoid including the instrument within the ligature, a circumstance which would lead to the slipping of the noose and failure of the operation. The hook is now to be withdrawn, and one end of the ligature cut off by scissars within a little of the noose. The remaining threads are allowed to hang out of the wound, so as to admit of their removal when they become loose, which does not, however, take place till the termination of the first four days, and they are frequently retained for a much longer period. At each time the wound is dressed, after the fourth day, the ligatures should be _gently pulled_, or, which is preferable, _twisted_, to disengage them, if at all loose, so that the wound may be more speedily closed. Before proceeding to any operation where bleeding is expected, the operator should provide himself with a few well-waxed threads, each twelve inches long, so that no delay may ensue on a division of large vessels. (107.) _Removal of Extraneous Matter._ Dirt is best removed by washing with a sponge or old linen rag and warm water. Other foreign bodies may in general be extracted by the finger and thumb. In some cases, however, it may be necessary to dilate or enlarge the wound with a fine-edged knife, in order to facilitate the removal of substances which, from their shape or situation, cannot be otherwise displaced.