REPARATORY INFLAMMATION IN ARTERIES. 5 



mation of the internal blood-clot is uncertain, or that when 

 formed it rarely fills the canal of the artery, or if it fills the 

 canal does not adhere to its internal coat, it is not to be 

 ranked among the means which nature employs for the sup- 

 pression of hemorrhage, for in ordinary accidents it contributes 

 nothing to those means. 



The permanent changes which take place in an artery and ia 

 the circulation through the limb, in consequence of the applica- 

 tion of the ligature, are precisely similar to those after the 

 division of an artery. Some of the effects of tying an artery 

 appear to be the following: to excite inflammation in the 

 middle and internal coats by having cut them through, and, 

 consequently, to give rise to the effusion of lymph (colorless 

 clot), by which the wounded surfaces are united and the canal 

 is rendei'ed impervious; to produce an inflammation on the 

 corresponding external surface of the artery, and at the same 

 time, by the exposure and inevital)le wounding of the surround- 

 ing parts, to occasion inflammation in the latter and an effusion 

 of lymph which covers the artery and forms the surface of the 

 wound. 



According to Jones, it is a fact that in most cases only a 

 slender clot is formed at first, which gradually becomes larger 

 by successive coagulations of the blood, and it is for this 

 reason that the clot is always at first of a tapering form, 

 with its base at the extremity of the artery. But tlie forma- 

 tion of this coagulum is of little consequence, for soon after 

 the application of the ligature the extremity of the artery 

 begins to inflame. The wounded internal surfaces of its 

 canal being kept in close contact by the ligature adhere, when 

 this portion of the artery is transformed into an impervious 

 and, at first, slightly conical sac. It seems to be entirely 

 owing to the effusion of lympli that this adhesion is effected. 



Hodgson (Diseases of the Arteries and Teins, 1815) con- 

 tended that the veins are liable to all those morbid chanores 



