336 LECTURE XIV. 



of the irritation which attends many forms of what is 

 called inflammation. From these processes backwards to 

 the phenomena of simple hypertrophy we find no recog- 

 nizable boundaries at all. We cannot at once say, when 

 we meet with a part enlarged in this way, and contain- 

 ing a greater amount of matter than usual, whether it 

 will retain its life or perish ; and therefore it is extremely 

 difficult in very many cases, when nothing at all is known 

 concerning the process through which such a change has 

 been produced, to distinguish simple hypertrophy from 

 those forms of inflammatory processes which are essen- 

 tially accompanied by an increased absorption of nutri- 

 tive material. 



In these processes too it is scarcely possible to refuse 

 the individual elements, when incited by a stimulus 

 directly applied to them, the power of taking up an 

 increased quantity of material ; at least it is opposed to 

 all the results of experience, to assume that such an in- 

 creased absorption must be due to a special innervation. 

 If we select a part which, in accordance with all observa- 

 tion, is entirely destitute of nerves, as for example, the 

 surface of an articular cartilage, we can, as was shown 

 many years ago by the beautiful experiments of Redfern, 

 produce altogether similar effects by means of direct 

 stimuli. In precisely the same way, there are not un- 

 frequently observed, in chronic diseases of cartilage, no- 

 dular elevations of the surface ; and upon examining 

 such spots microscopically we find the same thing that I 

 showed you in a former lecture in a costal cartilage 

 (p. 48, Fig. 9), namely, that the cells which at other 

 times are very delicate, small, lenticular bodies, increase 

 in size, swell up into large, round corpuscles, and in pro- 

 portion as they take up more matter, enlarge in all direc- 

 tions, so that at last the whole spot forms a little protu- 

 berance above the surface. Now in articular cartilage 



