100 CIRCULATING FLUIDS: 



be no excess of tlie acid, it must be added guttatim, and only 

 so long as it produces a precipitate, wliicli sometimes is not 

 observed for several hours after the addition of the acid. The 

 effect of the sulphuric acid should first be tried on a small 

 portion of the fluid. 



If it is difficult to lay down general rules for the quali- 

 tative analysis of all the proximate constituents that can 

 by any possibility occur in the fluids of the animal body, it 

 may easily be conceived that an attempt to lay down similar 

 rules for quantitative analysis would involve much greater diffi- 

 culties. Such a general quantitative scheme is, however, not 

 required, since quantitative analyses are always preceded by, 

 and based on, qualitative investigations. The fluids most 

 troublesome to analyse are the blood and the urine, on ac- 

 count of the large number of different substances that always 

 occur in them. The rules for the quantitative analysis of the 

 various fluids will be found in the respective chapters on the 

 blood, milk, urine, &c. 



CHAPTER II. 



THE CIRCULATING FLUIDS. 



The Blood. 



The following scheme will explain the arrangement which 

 we have adopted for the general consideration of the blood. 



1. The General Physiological Chemistry of the Blood. 



Its general physiological and chemical relations; the deve- 

 lopment of the blood-corpuscles ; the phenomena of circulation 

 and respiration ; the metamorphosis of the blood, and animal 

 heat. 



2. The Special Chemistry of the Blood. 

 The method of analysing the blood. 

 Healthy blood. 



Diseased blood. 



