| horses. 
672 CANKER. 
ple colour, and emit a powerful aromatic fra- 
grance. The inner bark of the branches is freed 
from the cuticle, dried in the shade, and sent to 
Britain as a drug; some of it flat and nearly a 
quarter of an inch in thickness, and some quilled 
like the bark of cassia or cinnamon, but consi- 
derably thicker than the latter, and suggesting, 
from its reed-like appearance, the generic name of 
canella, or “little-cane.” The dried bark has a 
slightly bitter and extremely warm and pungent 
taste ; and, when broken, emits an aromatic 
odour similar to that of a mixture of cloves and 
cinnamon. It is stimulating and gently tonic, 
and forms an useful ingredient in medicines for 
dyspepsia and a tonic gout, and a powerful correc- 
tive of the griping properties of resinous cathartics. 
It has a place in the list of cattle medicines, but 
is scarcely so useful, in that list, as a mixture of 
gentian and ginger. The ancient natives of the 
Antilles constantly used it in both their meat 
| and their drink; and many of the negroes were 
long fond of it as a condiment.—The laurel-leaved 
species, C. laurifolia, has very generally been 
confounded with the white species; but it does 
not grow to so great a height. 
CANKER. A disease in the mouth of young 
cattle. When the teething of a calf is unusually 
troublesome, pimples appear on the gums and 
on the membrane of the mouth, and, in many in- 
stances, grow into one another, ulcerate, occasion 
topical swelling, impair or destroy appetite, and 
excite general fever. Epsom salts ought to be 
administered, and diluted tincture of myrrh or 
solution of alum ought to be locally applied ; and, 
if the accompanying fever be severe, a fever drink 
ought to be administered. 
CANKER. A virulent disease in the feet of 
It is quite local; and either arises from 
accidental causes, such as high calkins or filthy 
litter, or is an accompaniment or a consequence 
of grease, thrush, or some other similar disease. 
It most frequently attacks the hind feet, and is 
generally difficult and sometimes impossible to be 
cured. The frog is the first part attacked, and 
becomes soft and fungous, discharging a sero- 
purulent matter, of a peculiarly offensive smell. 
The horny frog eventually disappears; and the 
sensible frog, instead of secreting horn, forms a 
substance somewhat resembling shreds of leather. 
The disease soon extends to the sole and other 
parts of the foot ; and, when it reaches the coffin 
bone, it may, in almost every instance, be re- 
garded as incurable. “Canker,” says Blaine, 
“has been likened to scirrhus and to cancer ; 
and, in some of its external characters, it some- 
what resembles fungus hematodes; but a true 
parity cannot be maintained with any of these. 
It can hardly be said to have any constitutional 
origin ; it is essentially local, seldom if ever spon- 
taneous. It appears oftener in hot weather than 
cold, and is more frequently seen in crowded and 
filthy stables than in well-regulated ones. It is 
now unknown in the army; and, as we may sup- 
CANKER. 
pose, were the same preventive causes applied, 
would be almost equally unknown elsewhere. 
The disease originates in various ways. One 
source, as supposed, but supposed only, is the 
high heels or calkins of the heavy draught-horse, 
which remove the frog from that pressure which 
seems so necessary to its healthy state. The 
state of wet and filth these horses stand in in 
some stables is a more likely source. Moisture 
applied to the frogs is a most active agent; it 
disorganizes the frog itself, and increases the 
growth of the horn of the heels, which aggra- 
vates the evil, as high heels and a full healthy 
frog are seldom seen together. Another common 
origin is neglected thrush, in which the suppura- 
tion, extending beyond the sensitive frog, in- 
flames the vascular sole, and extensive ulceration 
succeeds. Virulent and neglected grease will 
often occasion it ; and it isno uncommon circum- 
stance for quittor to degenerate into canker.” 
The proper treatment of this disease is to remove 
all exciting causes, to reduce the fungous growths, 
and to restore the healthy secretions. A perfectly 
clean stable and perfectly clean keeping are in- 
dispensable; the sedulous avoiding of all unctu- 
ous applications, and especially the preventing 
of all access of moisture, whether directly or 
through the surgical dressings, are essential ; the 
removal of the fungous growths must be effected 
by caustics, by the knife, or by both; and the re- 
storal of the healthy secretive function may be 
promoted by a long and patient series of topical 
applications. But the cure of canker is always 
both a nice and a very tedious process; and it 
ought riever, if possible, to be attempted except 
under the immediate direction of a veterinary 
surgeon. 
CANKER, or Carizs. A disease in fruit-trees, 
elms, larches, and other trees. It chiefly corrupts 
the juices, corrodes the substance, and destroys 
the vitality of the young shoots and branches of 
fruit-trees ; and it has long been known and de- 
plored as a most formidable enemy of orchards. 
Its symptoms vary considerably in trees of the 
same species, and very widely in trees of differ- 
ent genera. In some instances of its attack, a 
black speck appears upon the epidermis of a tree, 
assumes the character of an erosion, and gradually 
eats away the organism, till the branch becomes 
utterly enfeebled, and readily breaks; in other 
instances, a scrophulous-looking ring surrounds 
the branch, and eats its way inward till it reaches 
the pith; and in others, a black and thread-like 
line of disease originates in the pith itself, and 
exerts, in the direction of the exterior, a killing 
power upon all the branch’s functions. The first 
of these, however, is the most common commenc- 
ing symptom of the disease; and this is usually 
accompanied with an enlargement of the vessels 
of the bark ; but in some instances is dry, and in 
others sanious. In trees, such as those of the 
pyrus genus, whose natural sap contains a con- 
siderable quantity of free acid, it is generally 
