550 THE EXTERIOR OF THE HORSE. 



tinuous and dotted lines of different widths, the tracings furnished 

 by the four members of a trained horse whose gait was regular and 

 harmonious ; below these curves are found the notation of the contacts. 



At the beginning of the figure the horse is in the phase of projec- 

 tion ; then comes the beat PG, which is produced by the contact of the 

 posterior left foot. 



Between this beat and that of the opposite diagonal member, AD, 

 and almost in the middle of the interval which separates them, the 

 simultaneous beats of the two feet, AG, PD, of the left diagonal 

 biped take place, a synchronism which is rendered very evident by the 

 superposition of the notations A G, PD. 



Finally, between the third beat, AD, and the first of the following 

 step reigns a silence of a duration almost equal to that of the three 

 beats combined. 



The projection is indicated in the notation by the interval which 

 exists between the end of the contact of the anterior right member, 

 AD, and the commencement of the contact of the posterior left, when 

 the latter has commenced a new step. The duration of this projection, 

 according to the tracings, equals almost one-ninth of the duration of the 

 complete step. However, it evidently varies with each form of gal- 

 lop. M. Lenoble du Teil 1 claims it to be longer, for he considers it 

 as being equal, on the average, to one-fifth of that of the entire stride. 



In this succession of movements the ear has therefore perceived 

 three sounds, almost equidistant: the first produced by a hind-foot, 

 the second by a diagonal biped, the third by a fore-foot (Fig. 

 241, A). 



FIG. 241. Notation of the gallop with three times. 



(From M. Marey.) 



A. Representation of the three times. B. Representation of the number of feet which form the 

 contact of the body at each moment of the complete step. 



If now the successive bases which support the body during each step 

 are to be determined, it suffices to divide the notation (Fig. 241, B) by 

 means of lowering perpendiculars tangent to the beginning and the 

 termination of each contact. It is proved, then, that at the com- 



Lenoble du Teil, Etude sur le galop et la course, broch. in-8, p. 15, Argentan, 1880. 



