VETERINARY MEDICAL SOCIETY. 
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for want of these springs not being on the stretch, the crust has 
not had a direction downward, and therefore the coffin bone oc¬ 
cupies a higher part in the foot than nature intended that it 
should. 
Mr. W. Percivall. —Can it rise without any actual displace¬ 
ment ? 
Mr. Turner .—In proportion as the laminae lose the natural 
pressure from above, they will not receive their natural extension, 
and the horn will be secreted higher up than where nature had 
placed it. 
Mr. W. Percivall. —That would apparently bury the coffin 
bone. Does Mr. Turner mean to say that the bone is displaced ? 
Mr. Turner .—I do not mean to say that there is any displace¬ 
ment, but the bone is higher from the ground ; or there may be 
displacement, but no disunion. 
Mr. Goodwin. —Then all the bones must be out of their place, 
and the heels of the coffin bone must likewise be elevated. 
Mr. W. Percivall. —Two pieces of wood united together, can¬ 
not get out of the parallel without some motion between them. 
If the coffin bone be elevated, there must be displacement. The 
coffin bone has moved upon the hoof, or the hoof upon it. 
Mr. Henderson. —The coffin bone is suspended by these elastic 
laminae, but in consequence of contraction and rest it does not 
properly descend, and so in time assumes a fixed situation higher 
than nature intended. 
Mr. W. Percivall. —We appear to see more of the coffin bone 
in one specimen than the other. How has it arisen ? by dis¬ 
placement, or by growth ? or by the motion or absorption of the 
hoof? 
Mr. Turner. —Even the pastern bone is also elevated. 
Mr. Goodwin. —But if the anterior portion of the foot be ele¬ 
vated, the posterior is depressed. 
Mr. W. Percivall did not believe that there was any displace - 
ment between the hoof and the bone. The coffin bone may oc¬ 
cupy a very different position. It may become more oblique : 
if the heels are raised, the anterior part may be depressed, or 
there may be absorption. The resolution of the whole difficulty 
is probably this, that in a foot of altered shape there must be a 
corresponding alteration or absorption of the coffin bone. This 
may be the apparent rising of the bone, and this may explain 
Mr. Turner’s occult contraction. Displacement is an erroneous 
term. Mr. Turner tells me that I shall never alter his opinion. 
I neither expect nor wish it, but I wish to put it upon record that 
I differ from him in his theory of the disease, and still more ma¬ 
terially in the treatment of it. As I do not believe'that contrac- 
