256 MANUAL OF PHYSIOLOGY. 



the other view, we must needs say it is an act of death. But, 

 after all, this is a mere difference in degree, for how can we dis- 

 tinguish between the failure of a tissue to reintegrate or repair 

 its normal chemical changes upon which its life depends, and the 

 inevitable result of this failure (if prolonged beyond a certain 

 point), namely, its death ? 



When white cells congregate at a point from which the intima 

 is stripped from a vessel, their more active exertion possibly pro- 

 duces more ferment, etc., and at the same time they remain at the 

 injured part of the vessel wall, and the removal of the fibrin fac- 

 tors cannot occur, since the intima is destroyed ; hence local clots 

 are formed which extend over the injured surface, and by a 

 process of organization probably the repair of the denuded patch 

 can be accomplished. 



