110 INTERSTITIAL INFLAMMATION. 



tlierefore be blamed for basing at least the main divisions of the 

 subject upon it. 



3. Products of Morbid Growth derived exclusively from 

 THE Intermediate Apparatus of Nutrition. 



1. Interstitial Injiammation,^ 



§ 88. When the organism is mechanically injured at any 

 point, or exposed to any other sufficiently active source of irrita- 

 tion, the aggrieved part undergoes a series of changes, to the . 

 sum of which we apply the term " Inflammation." The name 

 directs attention primarily to the important part played by the 

 vascular system i-n the inflammatory process. The capillaries 

 become congested; the affected part grows red and hot. It 

 begins to swell ; the swelling is to be ascribed partly to the over- 

 distension of the vessels, partly to the escape of various con- 

 stituents of the blood into the tissues. The " inflammatory exuda- 

 dation" — the material which escapes from the vessels, and infil- 

 trates the tissues — is the more enduring product of inflammation, 

 and claims our chief attention, owing to its important connexion 

 with the course and issues of the process. 



§ 89. The inflammatory exudation consists, apart from its 

 fluid portion, of embryonic cells, which are characterised by the 

 lively amoeboid movements they exhibit. It was generally 

 believed a few years ago that these cells were produced exclusively 

 by proliferation of the connective-tissue corpuscles at the seat of 

 inflammation. The dazzling picture, in which we thought we 

 could distinctly appreciate the course of cell-multiplication, 

 exhibited in the immediate vicinity of the inflammatory^ exuda- 

 tion, instead of the stellate corpuscles of connective tissue, first 

 one, then two, then a progressively increasing number of round 

 cells, arrayed in ranks, which grew longer in proportion as they 

 approached the focus of inflammation, and finally mingled with 



* IntereUUdl, as contrasted witli catarrhal and parenchymatous in- 

 flammation, the former of which, bo far as it concerns us, is an inflam- 

 mation of mucous membranes {see Part II.), while the latter is identical 

 with cloudy swelling (see § 36). 



