17: 



THE FOOT IN ITS RELATION TO THE ENTIRE LIMB. 



(a) The position of the fore-limbs when seen from the 

 front is normal (fig. 143), when the limbs vertically support 



the body. A plumb bob let fall from 

 the centre of the shoulder joint should 

 coincide with the mesial plane of the 

 limb or divide the limb into two 

 equal parts. The fore-legs should be 

 separated to a moderate extent, in 

 order that the animal may have a 

 fairly large base of support, be sure 

 on liis feet, and not be likely to strike 

 himself in moving. A certain separa- 

 tion is also needful to accommodate 

 the great pectoral muscles. The 

 separation of the limbs should be ap- 

 proximately equal in front and behind. 

 The base of support then takes the 

 form of a parallelogram, and the im- 

 pulse of the hind-limb is conveyed in 

 a direction parallel to the direction of 

 movement of the whole body, a con- 

 dition which makes for stability and 

 allows all the power developed by the 

 hind-lim1js to be utilised in forward 

 movement. In simple language, when the hind-limbs are not 

 in line with the front they tend to push the body more or less 

 to one side instead of straisjht forward. 



When the toes are turned out (fig. 1-14) the plumb bob will 

 fall towards the inner side ; the chest is narrow, the limbs run 

 obliquely downwards and outwards, and the body-weight falls 

 more on the inner halves of the feet. Animals with this con- 

 formation are usually surefooted, but as the limb is not moved 

 straight forwards but in the arc of a circle they are more 

 readily tired than those of normal formation, the inside of the 

 limb is surcharged with weight, and the pace is relatively 

 slow. 



Again, in the calf-kneed condition, where the knees are too 

 close, the feet too far apart (fig. 145), we have perhaps the 

 maximum of undesirable factors. In this conformation either 

 the foot or the entire limb may be turned outwards. 



Fig. 143.— Normal position of 

 fore-limbs. 



