60 THE NAVICULAR DISEASE, OR CHRONIC 
in hunting, in which the synovial membrane is bruised or inflamed 
by the ground, as from high leaps into a deep stony lane. 
I think I hear some experienced practitioner asking me, how I 
know that the bruise and inflammation of which I complain is not 
seated in the sensible sole all the time, instead of the navicular, 
that joint seeming to be a favourite part with me:—My answer 
is, that the sensible sole and sensible frog may possibly be bruised 
at the same time, for aught I know; but this I do know, that 
only a few days are usually sufficient, when accompanied with 
good emollient treatment, to remove a lameness arising from a 
bruised sole or frog or both; but our skill is often baffled when we 
have to contend with the groggy foot inflammation ; and we are 
apt to take credit to ourselves if we remove the lameness in many 
weeks. 
I believe Mr. Coleman is of opinion, that a defective secretion 
of synovia is the first derangement of the navicular joint: this I 
take to be merely secondary, and for this reason,—having inva¬ 
riably found the navicular joint sound, and containing the due 
proportion of synovia in feet, however much contracted, which 
had always been known to have been free from lameness. The 
bruise and consequent inflammation either happen to the synovial 
membrane lining the flexor tendon where it articulates with the 
navicular bone, or to the synovial membrane covering the corre¬ 
sponding surface of the bone. To prove the decided character of 
this disease, I can confidently affirm, that it is uniformly confined 
to the under surface of the navicular bone, where it articulates 
with the flexor tendon, and never affects its upper articulating 
surface, where it assists in forming the coffin joint with the coffin 
and small pastern bones. 
I have frequently seen, in long standing cases of the navicular 
disease, not only all the cartilage of the inferior surface of the 
bone ulcerated, but also a material part of this small bone 
absorbed—almost annihilated; and yet its upper surface, just 
described, sound, with the cartilage entire, and synovial mem¬ 
brane quite perfect. The truth is, that in these cases of groggy 
or chronic foot lameness, the coffin joint is never affected, and, if 
it were not for the danger of raising our worthy ancestors from 
their own coffins , I would say the coffin joint never has been 
affected : I am sure it never has, except in those occasional in¬ 
stances of luxation where the violence may have been tantamount 
to a fracture, and terminated in leaving the leg and foot together 
a mere stump, by a general anchylosis of all the joints below 
the upper pastern. 
I must again advert to the important fact, daily and hourly 
