CHAPTER X. 



T ATROLOGY— (continued). 

 CHA]N"GES m THE BLOOB— {continued). 



DEFECTIVE EXCRETION. 



Sir TH01LA.S Watson, in his graphic language, says that " the 

 animal fluids are — the blood, the fluids that enter the blood, 

 and the fluids that proceed from the blood. 



" The fluids that enter the blood are of two kinds — 



" 1. Those by which it is renewed and enriched. 

 " 2. Those which enter it in order that they may be con- 

 veyed out of the body." 



A defective condition of the fluids which enter the blood to 

 renew and enrich it —namely, the chyle — produces the condition 

 already described — anaemia. A modified or altered condition of 

 the chyle — that is to say, chyle imperfectly developed, contain- 

 ing abnormal constituents, products of imperfect digestion or 

 elaboration, or directly derived from the ingesta — is a frequent 

 source of alteration in the blood and of disease. 



The fluids which enter the blood for the purpose of being 

 conveyed out of it are the products of the metamorphosis of the 

 chyle and tissue, accidental materials contained in the food, 

 products of imperfect digestion, superabundant nutritive ele- 

 ments unappropriated by the tissue cells, and undergoing 

 degradation within the blood-vessels, or in organs such as the 

 liver. For the removal of these effete materials the organs of 

 excretion are provided. When the organs of excretion are dis- 

 ordered or diseased, it follows that such products accumulate in 

 the blood, contaminate and render it unfit for the proper nourish- 

 ment of the body. 



