PLETHORIC STATE. 251 



the blood's motion in the aortic system is three times greater 

 than in the system of the venae cavcc. The same rule does not 

 apply to the pulmonary system of arteries and that of the 

 pulmonary veins, since it seems certain that the capacity 

 of the system of the pulmonary veins does not exceed, if 

 it even equals, the capacity of the system of the pulmonary 

 artery. 



When nutrition goes on vigorously, and an animal is freely 

 exercised within the limits of its strength, amidst circumstances 

 conducive to health and activity, the lines of the body are 

 sharp and angular without disposition to rotundity of parts, 

 the pulse of any considerable artery is full, strong, and swell- 

 ing, the contraction of the muscles of locomotion is steadily 

 energetic, the veins are full and tense, the secretions are every- 

 where abundant, and there is a boundless tendency to active 

 movement. Here the due balance is preserved between the 

 proportions of blood which belong respectively to the aortic 

 system and to the system of the vence cavce. When, however, 

 circumstances arise, the tendency of which is to weaken the 

 force of the circulation of the blood, a change appears to take 

 place in the distribution of the blood, the veins appropriating 

 to themselves a larger proportion than naturally belongs to 

 them. Nutrition may still go on freely, and the mass of blood 

 be even greater than under the state first described. Excretion 

 becomes diminished, and the solids become relaxed by the 

 presence everywhere of a larger proportion of fluid parts ; and 

 in particular, a larger amount of oil or fat accumulates in the 

 tissue appropriated to that secretion, whence the former sharp- 

 ness and angularity of the contour of the body gives place to a 

 more or less complete smoothness and rotundity. 



Thus the kind of management as to diet and regimen which 

 fits an animal like a horse for powerful and continued muscular 

 exertion, is very different from that which prepares an animal 



