176 Chapter VII 



the tissues or cavities of the body of a refractory animal, determines, 

 primarily, a localised inflammation, associated with which is a dia- 

 pedesis of many white corpuscles. Instead of aseptic inflammation, as 

 [186] in the case of the resorption of cells, there is produced, in antimicrobial 

 immunity, a septic inflammation at the point of invasion of the micro- 

 organisms. In this inflammation the redness and heat are slight, the 

 fluid part of the exudation is insignificant, but what is especially 

 characteristic is the large number of leucocytes which come up 

 towards the point menaced. This constancy of the inflammatory 

 reaction in natural immunity is one of the best proofs of the accuracy 

 of the view that inflammation is a phenomenon useful to the animal 

 organism, especially in its struggle against microbial invasion. As we 

 have devoted a whole volume to the discussion of the comparative 

 pathology of inflammation it is here unnecessary to discuss it further. 

 Since the publication of this book numerous articles on inflammation 

 have appeared, but none of them have undermined, in the least 

 degree, the fundamental bases of the phagocytic theory of inflamma- 

 tion. The view that this phenomenon really constitutes a healing 

 reaction of the organism is at present accepted by many investigators 

 in all countries. It is therefore needless to re-defend it. 



Although there still remain a certain number of points that are 

 not sufficiently cleared up in the essential mechanism of inflammation, 

 it is now proved beyond doubt that the sensitiveness of the cell 

 elements which here play a part, is one of the essential factors in the 

 process. The nerve cells which govern the vascular dilatation, the 

 endothelial cells which allow of the passage of leucocytes, and the 

 leucocytes themselves which escape from the vessels in order to reach 

 the point of entrance of the micro-organisms, all must be influenced 

 in a special fashion. In natural immunity the phagocytes exhibit a 

 positive chemiotaxis and this form of sensitiveness is a condition 

 indispensable to a state of immunity and to the disappearance of 

 the micro-organisms. 



In my eighth lecture on inflammation I have already set forth the 

 fundamental facts upon which rests the doctrine of the chemiotaxis 

 of leucocytes. During the last ten years numerous data corrobo- 

 rating these results, obtained first by Leber, Massart, and Charles 

 Bordet, and since confirmed by numerous other observers, have been 

 accumulated. 



In the resorption of blood corpuscles and of animal cells in 

 general, it is especially the macrophages which intervene, but in 



