OF FARRIERY, 



99 



The employment of the latter would render it 

 necessary to tie the whole surface of the 

 wound. The sides of the wound are to be 

 brought accurately together, and compresses 

 are then to be placed over the part, and a 

 roller to be applied with sufficient tightness 

 to make effectual pressure, but not so forcibly 

 as to produce a danger of the circulation of 

 the limb being completely stopped. If com- 

 pression can ever safely be trusted in bleedings 

 from large arteries, it is when these vessels lay 

 immediately over a bone, against which they 

 can be advantageously compressed. 



The ligature, being well known to be a 

 means of stopping hemorrhage, which is safe 

 and easy, and much less painful than former 

 methods, we need not longer search for such 

 remedies. It may indeed be set down as a 

 rule, whenever large arteries are wounded, 

 never to trust to any styptic application what- 

 ever ; but to have immediate recourse to the 

 ligature, as being, when properly applied, the 

 most simple and safe of all methods. In ex- 

 plaining the action of the ligature, when 

 applied round an artery, without including 

 the surrounding parts, the internal coat of the 

 vessel is torn through by it — experiments 

 which I have tried on the arteries of Horses 

 and dogs ; if the ligature be tied round with 

 sufficient tightness, it will cut through its inner 

 and middle coats, although it be immediately 

 removed, the vessels always become perma- 

 nently impervious at the part which was tied 

 as far as the first collateral branches, above 

 and below the obstructed parts. This divi- 

 sion of its internal and middle coats, produces 

 an obstruction to the circulation of blood 

 through its canal. 



'J'here must be a small quantity of stagnant 

 blood, just within the extremity of the artery; 



but this does not, in every instance, immedi- 

 ately form a coagulum capable of filling up 

 the canal of the artery ; in most cases, only a 

 slender coagulum is formed at first, which 

 gradually becomes larger by successive co- 

 agulations of the blood ; and hence the coagu- 

 lum is always at first of a tapering form, with 

 its base at the extremity of the artery. But 

 the formation of this coagulum is not material, 

 for, soon after the ligature has been applied, 

 the end of the artery inflames, and the wounded 

 internal surface of its canal being kept in close 

 contaxjt by the ligature, adheres, and converts 

 this portion of the artery into an impervious, and 

 at first conical sac. It is to the effused lymph, 

 that the base of the coagulum adheres, when 

 found to be adherent. Lymph is also effused 

 between the coats of the artery, and among 

 the parts surrounding its extremity. In a little 

 time the ligature makes the part, on whicli it 

 is directly applied, ulcerate, and, acting as a 

 tent, a small aperture is formed in the layer 

 of lymph effused over the artery. Through 

 this aperture, a small quantity of pus is dis- 

 charged, as long as the ligature remains ; and 

 finally, the ligature itself escapes, and the little 

 cavity, which it has occasioned, granulates 

 and fills up, and the external wound heals, 

 leaving the cellular substance a little beyond 

 the end of the artery somewhat thickened and 

 indurated ; but, if it should be in a situation 

 where you can apply a bandage, it ultimately 

 becomes absorbed. - 



As all styptics are not to be depended on, as 

 before stated, the judicious practitioner seldom 

 will apply them, as they generally tend to 

 irritate, and seldom do good : they are some- 

 times, however, proper to employ to diseased 

 sinfaces, where the vessels seem to have lost 

 their natural power, or disposition to contract 



