CHRONIC LAINIKNESS OF THE FEET. 81 



be placed behind the small pastern bone, rather than 

 immediately under it. 



In consequence of this false position of the navicu- 

 lar bone, it no lonoer receives its due share of the 

 superincumbent weight when the animal is stationary 

 or in slow motion ; but, what is much worse, it 

 occasionally sustains a most severe shock by any 

 sudden or violent movement of the animal ; in 

 which case, instead of the broad expanded surface 

 of the navicular bone conveying the impression of 

 the weight to the corresponding expanded portion 

 of the flexor tendon, it will be seen that the weight 

 can only be conveyed to the tendon by the anterior 

 edge of the lower articulating surface of the bone ; 

 and, to add to the embarrassment of the joint, it is 

 obvious that this position of the bone causes a more 

 acute angle of the tendon at this part than natural. 

 Now this is the identical spot, viz. the lining mem- 

 brane of the tendon at this part, which I have found 

 to exhibit the first lesion upon the inspection of 

 very recent cases of navicular lameness. 



Having proved to demonstration a very consider- Displacement 

 able displacement of all the three bones of the foot of ii'icVoot.""^^ 

 in these chronic lamenesses, and conceivino- that 

 these pathological facts are now placed beyond 

 the pale of argument, it necessarily follows, that in 

 our future treatment for the cure of navicular lame- 

 ness these important features of the disease must 

 not be disregarded. Whether the profession at 



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