ON CANKER. 
407 
driving the frog of its natural stimulus. Grease may likewise 
jccur from punctures of the feet, corns, &c. &c. 
Before I proceed to speak of the ^treatment, I beg to offer a 
•emark or two on frog pressure as in a very great degree a pre¬ 
ventive of this disease; and which, I think, when moderately 
ipplied, is as necessary for preserving the foot in health as the 
ron of the shoe to prevent wear and tear of the crust, &c. In 
nany cases of canker following grease in the hind legs, particu- 
arly in the cart horse, if the heels had been properly lowered, 
md different shoes applied, and the frog given a chance of re¬ 
ceiving some pressure, the disease would have been very much, if 
lot wholly, prevented. 
I have had an opportunity, for four or five years past, of wit¬ 
nessing the advantages of frog pressure on from fifteen to twenty 
coach horses, the property of one gentleman. He is so great an 
rdvocate for leaving the frog unpaired, that on one or two occa¬ 
sions he threatened to remove his horses* when by accident the 
men had paired away some portion of it; and in all his horses I 
io not remember one that had a frog with anything like canker, 
or even a thrush that required treatment; and the generality 
had good open sound feet. Besides which, if we had no other 
fact but that of the convex or pumice foot being so very rarely 
affected with this disease, I think that we should be satisfied as 
to the efficacy of frog pressure as a preventive. 
Treatment. —It would, perhaps, be quite impossible to lay 
down any one mode of treatment for all cases of canker. I am 
now speaking so far as regards medicine- With respect to the 
knife, I am a great advocate for it in all cases, perhaps more so 
than some of my brother veterinarians. I am likewise an advo¬ 
cate for the frequent repetition of dressing. In bad cases I dress 
every day; and in no case, where I can conveniently get at the 
patient, less than every other day ; for I am of opinion that can¬ 
ker is sometimes very much prolonged by going two, three, or 
more days between the dressing, thereby allowing a considerable 
time for the diseased action to go on, and during which time it 
will be found very often to have, what is commonly termed, under- 
run a great deal more of the sole. 
Having removed the shoes, I proceed to lower the heels, and 
then to examine the frog and sole, and remove all detached por¬ 
tions or separated parts; and carefully follow up the disease as 
far as it can be traced, although it will be found to extend some¬ 
times throughout the whole of the sensible and horny sole. 
Every separated portion must be removed; and this is found not 
only requisite at the first dressing, but at most subsequent ones; 
for if this is lost sight of the disease will still go on. 
