6 The Farmer's Yeterinary Adviser. 



dissolve and digest them, thereby rendering the inoculation 

 harmless. If, however, the bacteria are too numerous or 

 too poisonous (in themselves or their products) to be thus 

 easily devoured, the opposite result ensues, the cells of the 

 blood and tissues sent to dispute their invasion are them- 

 selves destroyed, and there takes place the death and re- 

 moval of a circumscribed portion of tissue, an extensive 

 suppuration and abscess, a spreading gangrene or ulcer, 

 or a fatal general infection. A small dose of such bacteria 

 is devoured, removed, and rendered harmless by the de- 

 fensive work of these exudation-cells; a larger dose may 

 establish a temporary stronghold in the tissues, which is 

 finally circumscribed, loosened, and thrown off as a slough 

 by the active agency of the investing animal cells around it, 

 while a still larger dose conquers the defending army, and 

 extends its sway over the entire body with grave or fatal 

 effect. 



INFLAMMATOEY EXUDATIONS AND EFFUSIONS. 



Tliese vary much in different cases according to the grade 

 and stage of the inflammation, the part affected, and the 

 siTbject of the disease. 



1st. Serous Exudations. These consist of the liquid ele- 

 ments of the blood, with only a limited amount of the 

 fibrine-forming element (fibrinogen), and consequently little 

 tendency to clot firmly. Tlie effused fluid is distinguished 

 from the liquid of mechanical dropsy by the presence in it 

 of the flbrinogen, of albumen, of cells, and of nuclei. The 

 dropsical fluid does not coagulate unless heated, and con- 

 tains less common salt and phosphates than the inflamma- 

 tory effusion. Serous exudations are characteristic of the 

 eai-ly stages of inflammation, and of inflammations of serous 

 membranes (pleura, peritoneum, joints) in strong, vigorous 

 subjects. They are especially dangerous by reason of inter- 

 ference with the functions of organs by pressure, as with 



