672 INFLUENZA, FOLLOWED BY RHEUMATISM. 
appeared in the hind leg, attacking the joints. Cattle, also, are very 
subject to metastasis of inflammation or rheumatism, under the 
name of joint felon, after inflammation of the lungs or their 
surrounding tissues. In all these cases it results from the intimate 
sympathy existing between parts of similar structural formation. 
In rheumatism of joints, occurring after inflammation of the pleura, 
it generally arises from the tone of the animal powers being so 
much weakened, by the result of disease or treatment, that there is 
not sufficient power left to resist this innate influence and tendency 
which parts of similar structure have to take on similar disease. I 
think if the primary disease could be combatted without too much 
lowering the animal tone, that there would not be the liability to 
take on these diseases. We generally find that the subject of 
these affections are animals much lowered by disease. In this case 
the animal had been bled, and also purgation had commenced with 
the smallest dose of aloes, and this purgation would, no doubt, soon 
have ended fatally if left unchecked. I have had several of these 
cases before, and long before I knew or understood any thing of 
their nature I can remember them well : it is to Mr. Percivall we 
are indebted for a clear elucidation of their nature. The first case 
I can recollect was a young troop mare of the 10th Hussars, affected 
precisely as the foregoing case, in which, after endeavouring by 
blistering, firing, turning out, and a treatment of twelve months' 
duration, I could effect no good, permanent thickening around the 
fetlock joint and along the tendon was the result, and the mare, 
never having done a day’s work, was cast as useless. This case 
puzzled me very much at the time, for it had all the appearance of 
a most violent strain of the back sinews, which I knew by no pos- 
sibility could have happened; and I remember the peculiar shifting 
of the lameness from leg to leg without any obvious cause. I have 
had several cases of late years, and they have always been tedious, 
troublesome, and uncertain affairs, requiring long rest and exten- 
sive counter-irritation after the first severe inflammatory symptoms 
had passed over. Permanent thickening of the joint is too often, 
however, the result. I have noticed the intense soreness existing 
on pressure on the internal part of the leg just above the fetlock 
joint, and that there was in this case an enlargement felt under the 
ringers about the size of a small pea, exquisitely tender : this 
enlargement I have noticed before in other cases, and I suppose it 
is the sheath of the nerve enlarged and thickened. 
The great pain existing in these cases arises from the distention 
of the capsule and bursae by synovia, which presses in every 
direction upon the highly inflamed inelastic ligaments and fascia. 
I mentioned in this case that I had tested the specific gravity of 
the urine by the urinometer. The urine throughout this disease 
