In the Stable, Field, and on the Road. 101 



rule applicable to all classes of horses. Navicular 

 disease never occurs suddenly, is never caused by 

 bruises from stones as alleged, nor does it appear as 

 a primary affection. The coffin-bone having the 

 whole weight and exertion to sustain is always the 

 first to suffer, and it is when an alteration from the 

 normal state takes place in the coffin-bone and the 

 other component structures of the foot, that derange- 

 ment of functions and stress of pressure is imposed upon 

 the navicular bone. The coffin-bone undergoes more 

 change in physical formation and far more rapidly 

 than occurs in other bones, I may say of any animal, 

 for the reason that no bone is placed under so 

 many complications of influence and misapplied art 

 and exertion combined. The semiluna crest and the 

 normal asperities of the coffin-bone become absorbed 

 under the influence prevalent by which the attacking 

 processes for the tendon, the planta band and the frog, 

 are all weakened and their positions become altered. 

 The navicular-bone is more and more called upon to bear 

 pressure when its normal bulk would lack space, therefore 

 absorption of its substance takes place from within, until 

 at length the outer surface breaks down ; being always 

 on its lower and posterior surface where the ulcerated 

 apertures one or more are seen, whence lymph issuing 

 becomes attached to the tendon, by which effort of 

 nature the structure becomes in some measure fixed 

 together, and the otherwise unsuppor table friction is 

 diminished. For the treatment of this disease I repeat 

 the words of Professor Gamgee, in a lecture upon this 

 subject delivered by him at the New College of Veterinary 



