CENTRE OF GRAVITY. 3 



will allow them to dispense with, but without which they could not 

 rise above this empirical knowledge, appanage of the ignorant or of 

 the coxcomb, who accepts under the same title the true and the false, 

 and who is incapable of distinguishing otherwise than by the routine 

 with which he proceeds. 



If the knowledge of the horse is an art, it is especially one which 

 consists in observing, comparing, and judging according to positive 

 information. Besides, it is necessary, in order to reach perfection, to 

 have observed much, to have put into practice that faculty which makes 

 the clinician, the connoisseur, and the artist. It is when such an edu- 

 cation is carried to a considerable extent that we succeed in seizing at 

 once what good or defective qualifications the horse possesses, and that 

 it is possible to form a just conclusion by appreciating to what degree 

 the good qualities exceed the bad. 



CHAPTER II. 



CENTRE OF GRAVITY. 



THE simultaneous actions of the force of gravity upon all the molecules 

 of a body may be considered as so many small parallel forces having the same 

 purpose and the same direction, whose total sum is the weight of the body, and 

 whose result is applied to one point which is the centre of gravity. 



The vertical pressure of the centre of gravity to the ground is called the 

 line of gravitation (line of gravity, Raabe & Bonnal). We have just seen that 

 the result of these forces is equal to their sum, and that the position of its point 

 of application depends upon the intensity of its components. 



All the actions of the force of gravity being equal for each molecule of the 

 same kind, if these molecules of a body are uniformly distributed, in a word, 

 if the latter be homogeneous, it will in all its parts be equally attracted by this 

 force. Therefore, nothing will be easier than to determine the centre of gravity, 

 especially if the body has a geometrical form. Special procedures are employed 

 to determine the location of this centre in a body, whatever may be its form. 

 We will not speak of this at present. 



Seldom, however, are bodies found in conditions sufficiently homogeneous for 

 its determination to be simple. Certain parts are much more dense than others, 

 and therefore the force of gravity attracts them more. The result of this is that 

 the centre of gravity, instead of being situated in the middle of the body, is 

 drawn nearer, as has been seen, to the parts which weigh the most. This is 

 observed in organized bodies. 



Its Determination in Animals. In animals new difficulties arise. The 

 vital phenomena being only the phenomena of movement, the material particles 



