DISEASE OF THE NAVICULAR JOINT. 537 



has done more harm than good. The measure which has 

 been attended with the greatest advantage is shoeing with a 

 wide-webbed dish shoe, having a leathern sole, for the pur- 

 pose of protecting the seat of the disease, and being rather 

 higher at the toe than at the heel ; because a prominent 

 healthy frog is found an accompaniment to a pumiced foot, 

 and the horse can bear upon the frog when he dreads to let 

 the sole touch the ground. Formerly a different mode was 

 practised by some persons, which was to apply a shoe so 

 narrow in the web as to cover the crust only, but of suffi- 

 cient thickness to elevate the sole above the chance of 

 pressure from the ground. This invention is said to obviate 

 the effects of stones, gravel, &c., getting under the wide 

 webbed shoe, which sometimes lamed the horse ; and it is 

 said that pumiced horses even go best in these kind of 

 shoes. In some cases, however, no shoe answers so well as 

 a strong bar shoe. 



DISEASE OF THE NAVICULAR JOINT, OR NAVICULARTHRITIS. 



Groggy lameness is the term by which this affection has 

 been principally known to horsemen, and which, hke many 

 other names, served to characterize many of its evils. It 

 is but due to Mr. J. Turner to state, that, by his ample and 

 scientific investigations, the navicular joint disease is now 

 ranked among the recognized afflictions of the horse : and 

 if, unfortunately, we have little hope of finding an efficient 

 remedy for it, we at least do not grope in the dark, and 

 torment sound parts, to the anguish of the animal, and the 

 demonstration of our own ignorance. 



The causes of the affection may be strictly called here- 

 ditary or predisposing: the tendency may exist from birth. 

 Pressure and concussion are, in general, the remote 

 causes; the proximate is found in inflammation, leading 

 to ulceration, or some ossific deposit. Mr. Turner lays 

 much stress on contraction with the hollowed arch of the 

 sole as a cause, which acts by drawing the frog upwards : 

 other writers, without denying that some displacement is 

 occasionally found, are not wiUing to acknowledge this as a 

 cause. The perforans tendon is inserted into the most 

 backward portion of the sole belonging to the coffin bone. 

 To gain this point it has to pass underneath the navicular 



