304 



THE EXTERIOR OF THE HORSE. 



Fig. 101. 



Fig. 1U2. 



while it becomes more vertical when it is too short. In the first case, 

 the horse is low-jointed ; in the second, he is qualified straight- jointed 

 (Fig. 101 and Ficr. 102). 



The close relationship which associates long-jointedness with low- 

 joiiitedness is easy of comprehension, the pastern becoming less and 



less a column of support, and 

 more and more an elastic spring 

 in proportion as its length in- 

 creases. We have seen above 

 that the arm of the lever of 

 resistance (weight of the body) 

 elongates and imposes greater 

 efforts upon the muscles and the 

 ligaments. A sjjring also gives 

 all the more as it is more elastic 

 and as the pressure which it sup- 

 ports is greater. This is precisely what takes place in a long-jointed 

 pastern, which is at the same time nearly always low-jointed, because it 

 is relatively weak and flexible under the weight and the reactions of 

 the body. 



Some horses, nevertheless, are exceptions. Either from the great 

 resistance of the fibrous ligaments or the tendons to traction, the mode 

 of articulation of their bones, a greater energy of their muscles, an 

 intensity of action which is more effective from the length of the arm 

 of the lever and the perpendicular incidence of insertion, or, finally, 

 for some other cause, these animals redeem the excess of the length of 

 the pastern, and mitigate the evil effects by a less oblique direction. 

 These instances, however, are rare, which is nothing but natural, as we 

 have just seen. 



Most authors who define the direction of this region estimate it at 

 about 40 to 45 degrees, in such a manner as to form with the fetlock an 

 angle of 130 to 135 degrees. Vallon and M. Lemoigne are the only 

 ones, to our knowledge, who seem to have measured this inclination with 

 some care upon the living horse or upon the skeleton. Aside from the 

 purely theoretical idea that the pastern should have a direction inter- 

 mediary between the absolutely vertical and the horizontal, it has been 

 believed to be good logic to recommend a mean obliquity of 45 degrees, 

 without perceiving that this argument is faulty, first of all, in its 

 premises, since it is not based upon facts. 



The mean obliquity, in our opinion, oscillates around 60 degrees 

 upon the horizon, in the anterior members, and 65 degrees in the pos- 



