440 
LAMENESS IN HORSES. 
formed:—The horse being cast, a (small) trocar was plunged into 
the dependent part of the swelling. The withdrawal of the stilette 
was followed by profuse efflux of limpid synovia, both tumours 
being manipulated in order to completely empty them. This being 
done, three syringe-fuls of iodine mixture—one part tincture to 
three parts water—were injected, which proved barely sufficient 
to distend the sac as before. The injection was suffered to remain 
in three minutes, after which every pains were taken to squeeze 
all of it out. The horse walked to his stable lamer than before; 
and the pain and lameness increased, and slight fever ensued. 
Both fever and lameness, however, gradually abated, so that, after 
three weeks had elapsed, his owner being of opinion the animal 
was fit for work, took him away. Nothing was seen or heard of 
the patient for upwards of three months afterwards, when he was 
by special desire brought to the College for examination. So re¬ 
duced was the diseased hock found, that no more than one-and-a- 
half inch remained between its measurement round and that of the 
healthy hock, notwithstanding the time had been when the former 
exceeded the latter by fourteen inches. 
Case II, however, although similar in its general character, 
proved, under like treatment, fatal. An entire cart-horse exhibited 
his near hock nearly double the size of the off, from the presence of 
a very large thorough-pin, which had been several times fired. The 
diseased hock measured twenty-two inches, the sound hock fif¬ 
teen. The tumour is low (compared to the one in the former case), 
and there is accompanying it enormous distention of the capsule of 
the hock joint. Nevertheless, the subject being given up for ex¬ 
periment, the operation was proceeded with. The trocar was in¬ 
troduced, and a pint of synovia flowed out. The iodine injection 
was thrown in, and retained three minutes within the cavity. But 
the whole of it could not be made to pass out again, in consequence 
of albuminous matters, discovered to have become effused into the 
cavity, by, after the animal had risen, albuminous synovia flowing 
from the opening. Pains in the limb and fever followed; and on 
this supervened swelling, in particular of the hock joint, which at 
first fluctuated as though purulent matter was collected, and after¬ 
wards emitted a viscous colourless discharge containing pus glo¬ 
bules. This went on to ulcerations appearing, and these gave 
vent in places to pseudo-membranous discharges from the joints, 
having spots upon them indicative of gangrene, which at length 
was found to have commenced within the joint, under the resorp¬ 
tion of the ichor. And of gangrene, as was presumed, the animal 
at length sank. 
The sacs of the thorough-pin were found inwardly rose-coloured 
and mammillated, the same as in a suppurative wound. Within 
