266 Inflammation. 



The acceleration of the blood current which is seen in the early 

 stages depends on the passage of the blood from narrow into wider 

 channels [an explanation sufficient for the short period required for 

 the filling of the additional space afforded by the dilated lumen of 

 the vessel, but not clearly satisfying for its continuation even for the 

 time it does prevail before stasis sets in, and for its longer persist- 

 ence at the periphery of the inflamed area] ; the slowing of 

 the current upon the transudation of the plasma, and the endothelial 

 changes, both of which tend to cause a more concentrated condition 

 of the blood. [Here, too, there should be considered the probability 

 of relative inefficience in the outflow of the blood, loss of tone of 

 the venous walls and loss of elasticity of the surrounding tissues, 

 local compression of the walls of the capillaries and venules by exu- 

 date and proliferating or swollen and degenerate cells, all of which 

 introduce elements of a relatively passive factor in the process for 

 retardation of the escaping current.] The marginal deposition 

 of the white corpuscles is explained by Hering and Schklarewski by 

 the fact that when liquids containing light bodies in suspension are 

 passed through tubes these bodies tend to move along the periphery 

 as the rapidity of the current is slowed ; they call attention to the 

 lower specific gravity of the white in comparison with the red cells 

 and their viscidity and tendency to adhere from their tactile irri- 

 tability. The movement of these cells, physiologically determined 

 everywhere by their tactile and chemotactic sensibility, is stimu- 

 lated in inflamed tissues both by the causes of the inflammation 

 and by the lesions occasioned by these causes. The studies of 

 Pfefifer, Buchner and others have made us acquainted with a series 

 of substances which possess marked power of attraction for leu- 

 coc>'tes, especially certain proteins of the bacterial body ; and in the 

 destruction of tissue induced as a primary effect of the untoward, 

 influences exerted by the causes of inflammation certain chemical 

 substances, as the alkali albuminates, are set free which have a sim- 

 ilar attractive influence upon the leucoc>i:es. According to Thoma, 

 even a variation in the amount of saline matter in a tissue will 

 occasion a movement of the leucocytes. 



The spaces produced between the endothelial cells are appar- 

 ently not primarily due to perforative efforts by the leucocytes, but 

 result from distension of the vessel or from shrinkage of the endo- 

 thelial cells ; and the leucocytes possessing tactile sensibility, closely 

 adapting their substance to the surface and fitting into every varia- 

 tion, extend their processes, tentatively and uncertainly, through 



