GENERALITIES OF THE GAITS. 



475 



dejuger). Lastly, when the hind are in front of the fore (a gait they 

 style unduly lengthened), the animal is said to *' overcheck," to " over- 

 cover" his steps (se mecouvrir, se mejuger). 



They say also that the horse traih hhmelf (.sf piste), when one of 

 the posterior bipeds marks its imprint u])()n the same transverse line 

 as tiie anterior foot which is diagonally opposite to it; again, the im- 

 j)rint of the ])osterior foot in qnestion may he made in front or behind 

 that of the diagonal anterior foot, and then the horse miatrdils himself 

 {se depiste). These terms are only used for the gallo]). 



Since the time of Solleysel ' there have been distinguished in the 

 evolution of a member two princij)al phases or periods, the contact 

 with the ground and the elevation, during which this member supports 

 a part of the Aveight of the body or, on the contrary, is completely 

 lifted from the ground. We have seen (page 1 95) that as soon as a 

 member has passed successively thnnigh the two phases, the body lias 

 j)assed over a distance designated under the name of complete step. 

 The two bij)eds (anterior and posterior) are, in fact, conjointly con- 

 cerned in its execution ; and, even as an anterior member, for example, 

 is incapable of taking two steps in succession without the intervention 



Fig. 171.— Scheme of the movement of a member during the phases of contact and elevation. 



of its congener ; even so, also, the anterior bi})ed is unable to carry 

 itself a certain distance in advance of its primitive position unless the 

 posterior biped accomplishes exactly the same movement.^ 



On the other hand, it is known that during the evolution of any 

 member (Fig. 171), the centre of movement, H, of this member, and, 

 in consequence, the centre of gravity, j)rogresses from H° to H", — 



• De Solleysel, Parfait mareschal, ed. de 1693, 2e partie, p. 66. 



* C. Bourgelat. Traits de la conformation extiJrieure du cheval, p. 245. 



