TERMINATIONS OF INFLAMMATION. 71 



there is a sinus_, or rather a contracted part of the general 

 cyst, running underneath the skiii, and not inclined to heal. 

 Instead of running a bistoury into this and laying it open 

 across the direction of the muscular fibres, make a free in- 

 cision the other way, in the proper direction, upon the cavity 

 of the abscess, so as to allow the matter to escape in that situa- 

 tion also, and you will have a more rapid cure. The same 

 observation applies to abscesses over joints. (Liston^s Lec- 

 tures, ' Lancet,^ June 1, 1844.) 



Ulceration may be defined to be a loss of substance, 

 on any surface attended with the secretion of unhealthy pus. 

 Ulceration cannot be considered as a healthy action. Rather 

 may we view it as a tardy or unhealthy suppurative process 

 in which absorption is more active than secretion. It is an 

 effect of, although not strictly speaking, a termination to, 

 inflammation : were it so, its consequences would be in the 

 highest degree lamentable. We have an example of a kind 

 of internal ulceration in the case of the abscess. No sooner 

 is pus deposited than the solid tumour begins to disappear 

 under the effects of absorption or ulceration : a process which 

 in this instance is brought about by the pressure X)f the puru- 

 lent matter. The result of the absorption is, that a cavity 

 is formed for the pus, which, in the end, becomes so thin in 

 one particular spot, that it bursts, and gives vent to the con- 

 tained matter. Ulceration, therefore, differs from abscess, 

 not so much in absorption as being on a surface : abscess 

 lies within a sac, and the abscess ceases when the sac 

 bursts, the wound becoming a suppurating sore or an ulcerat- 

 ing surface. Ulcerations are common in horses. We see them 

 upon the membrane of the nose in glanders ; and upon the 

 skin in farcy. One of the best examples of ulcerative in- 

 flammation is afforded by the skin of the heels ; a part which, 

 in consequence of its remoteness from the source of circu- 

 lation, is very subject to inflame, and in that state is prone 

 to run into ulceration : hence the origin of the troublesome 

 ulcers we meet with on the heels in cold and wet weather. 

 Some parts are more disposed to ulceration than others ; a 

 circumstance ascribable to their relative degrees of vascu- 



