350 PRINCIPLES OF VETERINARY SURGERY 



taken place, it creates a toxi-infectious nodule in 



the connective tissue ; that is to say, — a point at 

 which the first morbid phenomenon is marked by 

 the death of a certain number of cellular elements. 

 The moment it is attacked the tissues react; the phenomena 

 of vaso-dilatation make their appearance. The blood car- 

 ried in large quantities to the exact spot affected, throws 

 into the abscess in miniature a considerable amount of lym- 

 phatic elements, which, being added to the fixed cells orig- 

 inally attacked, constitutes, with the serum exuded, the first 

 evidence of pus. The latter, increasing in quantity through 

 the incessant addition of new elements and the dissolving 

 action of microbian diastases, hollows out a cavity and press- 

 es upon the surrounding tissues. The tissues build protect- 

 ing materials, — the pyogenic membrane, — around its mass. 

 The pyogenic membrane of the author's is the patent mani- 

 festation of these protective elaborations. When the abscess 

 has been established, its formation, which finally results in 

 the encystment of pus, may be regarded as a victory for the 

 tissues, as against the micro-organisms. The formation of 

 pus is, in the absolute sense of the word, a cvirative effort, 

 a step in the process of recovery. 



HOT, OR ACUTE, ABSCESSES. 



I. SUPERFICIAL ABSCESSES.— In every species, 

 hot superficial abscesses are announced by well known local 

 and general symptoms. 



(a) Local Symptoms. — At a given point of the surface 

 of the body there is noticed, in addition to a tumefaction, all 

 the signs of inflammation. The tumefaction is hot, painful, 

 diffuse and cedematous, and the skin, when not masked by 

 hair or pigment, is reddened. After a time, varying with the 

 character of the abscess, the original tumor becomes con- 

 tracted, localized, diminished in size and more projecting. 



