648 THEORY OF COAGULATION. 



vital energy, in the different orders of animals ; 

 being greater in birds than in mammalia, and 

 greater in the latter than in reptiles and fishes. 



2. That as the temperature of arterial is higher 

 than that of venous blood, so does the former co- 

 agulate more quickly and firmly than the latter.* 



3. That as the vital energy of animals is always 

 diminished by reducing their temperature below 

 the natural standard, so is the coagulation of the 

 blood retarded by the same means, and wholly 

 prevented by long continued cold.f 



4. That the blood of individuals belonging to 

 the sanguine or dynamic temperament, coagu- 

 lates sooner and more firmly than in such as are 



* We also learn from the experiments of Hunter and Thack- 

 rah, that arterial resists putrefaction longer than venous blood. 

 And Bellingeri states, that while the former is positive, the latter 

 is in a negative state of electricity. However this may be, they 

 are certainly plus and minus in relation to temperature, or the 

 quantity of caloric in each, while circulating through the body. 



f Sir Charles Scudamore found, that human blood which 

 began to solidify in four minutes in air at 53, underwent the 

 same change in two minutes and a half at 98, and in one minute 

 at 120 : again, that blood which coagulated firmly in five 

 minutes at 60, required seventy minutes to become solid when 

 reduced to the temperature of 40. Nor is it true, as stated by 

 Mr. Ancell, on the authority of Mr. Prater, that when blood is 

 suddenly raised to 140 and 150, its power of coagulation is de- 

 stroyed ; for in numerous experiments of my own, it took place 

 rapidly in the blood of sheep at all temperatures, from 110 up 

 to 150, and almost instantaneously, when the cups in which it 

 was received were placed in water at 180, owing, doubtless, in 

 the latter case, to solidification of its albumen, which takes place 

 immediately at temperatures above 156. 



