GRANULATION, ULCER ATION. 497 



surface gives way, or without giving way is directly 

 transformed into a soft, diffluent mass. This mode of 

 suppuration gradually yields the so-called granulations 

 which always consist of a tissue, where, in a small quan- 

 tity of soft intercellular substance, more or less numerous, 

 and, at least in the strictly proliferating stage of the 

 granulations, round, cellular elements are imbedded. 

 The nearer we come to the surface, the more do the 

 cells, which in the deeper parts were mostly uni-nuclea- 

 ted, present divisions in their nuclei, and on the extreme 

 confines they can no longer be distinguished from pus- 

 corpuscles. Then a detachment of the epithelium is 

 wont to take place, and finally it may be that the basis- 

 substance liquefies and the individual elements are set free. 

 If the proliferation continues abundant, the mass keeps 

 constantly breaking up, the cells pour themselves out 

 upon the surface, and a destruction takes place, which 

 makes deeper and deeper inroads into the tissue, and 

 throws up more and more of its cells upon the surface. 

 This is an ulcer properly so called. 



According to the common notion, which supposed the 

 pus to be derived from some exudation or other, this 

 kind of ulcer ation was not at all easy of comprehension ; 

 people always found themselves obliged to assume a 

 special kind of transformation in the tissue in addition to 

 the suppuration, and at last they went so far as to attri- 

 bute a certain chemical solvent power to pus. But by 

 surgical experiments the conviction has long since been 

 acquired in the most manifold ways that pus has no sol- 

 vent power. Bones have been placed in cavities full of 

 pus and left there for weeks, and when they were after- 

 wards weighed, they had if anything become heavier, 

 through the absorption of fluid matters, but no softening 

 had been produced excepting that occasioned by decom- 

 position. How far the tissue is destroyed by real solu- 



32 



