208 
VETERINARY MEDICAL SOCIETY. 
Mr. J. Turner replied, that all he contended for was, that a 
portion of the bone was elevated above its natural place. He 
did not believe there was any displacement; but if, in the healthy 
specimen, there is hoof for half an inch above the apex of the 
coffin-bone, and in the diseased specimen the bone and the hoof 
are on a level, there must be alteration of position. lie then 
produced another specimen, to show that contraction from below 
upward may exist to a considerable degree, and the navicular 
joint be uninjured. 
Mr. W. Percivall. —This is a case of lateral contraction, 
which cannot exist without a concave sole ; and the consequence 
of that will be, elevation of the coffin-bone. 
Mr. J . Tu7 ' tier .—The horse was sound, because there was no 
navicular lameness. He presented another specimen, which had 
a fair appearance to the eye, but, when pared out, the sole would 
have the form of a basin. The coffin-bone was elevated above 
the crust, and was much diseased. 
Mr. W. Percivall wished that Mr. Turner had brought for¬ 
ward a lateral section of a foot of this kind ; it would have given 
a more accurate idea of the position of the coffin-bone, and the 
degree of absorption. Does not Mr. Turner meet with many cases 
of navicular disease with the frog sound and prominent? and 
may not the disease then arise from bruise of £he frog ? 
Mr. J. Turner had seen navicular disease with prominent 
frog, and thought it might occasionally arise from bruise of the 
frog. 
Mr. W. Percivall thought it a case of frequent occurrence. 
Mr. J. Turner believed that, in the great majority of cases, 
the disease arose from something wrong in the foot. He could 
even, at first, generally see an alteration of form in the foot. 
There was never the prominent, bold appearance of the perfect 
foot. - . 
Mr. W. Percivall thought that many of the symptoms de¬ 
scribed by Mr. James Turner would apply to other diseases of 
the foot; indeed, his best symptom seemed to be the absence of 
every other apparent cause of lameness. Could Mr. Turner 
always distinguish between the navicular disease and shoulder 
lameness ? 
Mr. J. Turner thought that the walk and action would always 
indicate shoulder lameness ; he should, however, avail himself of 
every circumstance in his power to guide his judgment, and run 
the horse on different surfaces. A mistake could hardly be made 
in shoulder lameness., and he was not singular in the confidence' 
with which he expressed this opinion. 
