406 
ON CANKER. 
Now, every spring since I left you at college, in 1811, I have 
operated upon foals at all ages, from ten days old to four months, 
and have, on all occasions, been convinced of its being the most 
eligible period for castrating. 
Operating thus early produces very little change in the appear¬ 
ance of the colts, as they are generally well in ten days; and in 
every case they grow larger than when castrated later. 
Colts are foaled with their testicles in the scrotum, which remain 
there (in ordinary cases) until the fifth or sixth month, when they 
are taken up between the internal and external abdominal rings, 
and there they remain until the eleventh, twelfth, or thirteenth 
month, all depending upon the degree of keep, as in some that 
are particularly well fed the testicles can at all times be found in 
the scrotum. 
Were the testicles drawn up into the abdomen, they would be 
too large to pass through the internal abdominal ring at the time 
they are wanted to prepare for seminal secretion; which is occa¬ 
sionally the case, and at once accounts for our meeting with 
horses that are said to have only one stone. I have seen one 
instance where both were wanting in the scrotum at four years 
old. ✓ 
I am, 
Your obedient humble servant, - 
It. Brettargh. 
ON CANKER. 
By Mr. Palmer. 
[Read at the Veterinary Medical Society.] 
CANKER is a specific inflammation of the frog, or of any of 
the vascular parts of the foot; and, if not arrested in its com¬ 
mencement, will go on to a separation of the horn from all the 
sensible parts by a suppurative process, and the growth of a pe¬ 
culiar fungus from all the secreting surface, and which is very 
difficult to keep under. 
The causes are various. A very common one I believe to be 
neglected thrush and grease, combined with the elevation of the frog 
from the ground by the increased height of the heels of the crust, 
which is so commonly found in greasy legs. It is from this cause 
probably that the hind feet are so frequently the subjects for treat¬ 
ment. Besides which, the hind feet are exposed a great deal 
more to wet and moisture than the fore ones; assisted till farther 
by the increased height of the calkins of the shoes, wholly de- 
