CHAPTER V. 



CONTAINING A RECAPITULATION OF THE PRINCIPAL .FACTS AND 

 CONCLUSIONS THAT ARE MENTIONED IN THE PRECEDING PAGES. 



THE separation of the blood into crassamentum and serum, 

 in a given time, appears to be in proportion as the heat in 

 which it stands is nearer to that of the human body (xxxv). 

 The heat in which the blood is kept should therefore be at- 

 tended to, when we draw inferences from the proportions of 

 these two parts. . 



The florid colour of the surface of the crassamentum seems 

 to be owing to the air. The venous blood, in passing through 

 the lungs, has a similar change produced upon it, or becomes 

 more florid by the time it gets into the arteries; and this 

 florid colour is again lost in passing from the small arteries into 

 the veins, especially if the person be in health. But some- 

 times in diseases it does not undergo this change, but comes 

 florid out of the veins (xxxvi). 



Neutral salts, on being mixed with the blood out of the 

 body, make it more florid : they likewise, if used in great 

 quantity, prevent its coagulation when exposed to the air, and 

 some of them allow the lymph to be precipitated, or to jelly on 

 being diluted with water (xxxvn). But we are not to con- 

 clude from thence that they would produce the same effects 

 when used as medicines ; for then they are only given in small 

 quantities (xxxvin), and may have their properties changed 



(xxxv.) See Notes u and in. 



(xxxvi.) On the colour of the blood, see Notes iv and v. 



(XXXVIT.) The effects of neutral salts on the colour and coagulation 

 of the blood are discussed in Notes iv, vi, and vn. 



(xxxvin.) A very weak saline solution will prevent that aggregation 

 of the corpuscles, which is characteristic of the blood in inflammation. 

 The effect may be easily tried on the regularly buffy blood of the 

 horse (see Note xxni). On the different effects of different quantities of 

 salt on coagulation, see Note vn. 



