DISEASES.--Birds which seldom enjoy the benefit of fresh and pure air, prisoners destitute in their confinement of the means of exercise, must be particularly subject to the common diseases which have been named, and also to many other peculiar ones. The following are some of the disorders incident to canaries.
1. _Rupture_, or _Hernia_: this is very common among young birds, and is a kind of plethora, which produces inflammation in the bowels. The symptoms of this disease are, thinness, the skin of the belly transparent and distended, covered with little red veins surcharged with blood, the bowels are black and knotted, and descend to the extremity of the body; there are no feathers on the diseased part; the invalid does not eat, and dies in a few days. Too nutritious, or too much food, being the cause of the disease, the only remedy is a very severe regimen, and even then it can be cured only in its first stages. The diseased birds must be immediately removed, and fed with nothing but lettuce or rape-seed, in very small quantities. A bit of iron should also be put in the water, and everything be done to invigorate and purify them. It is very rare for young birds which are brought up by their parents to suffer from this disease, as they never over-feed them. In bringing up by hand this moderation should be imitated, and they should neither be over-fed nor pampered.
2. _The yellow gall in the head and eyes_, arises from over heat; a cooling diet is therefore the only remedy. If the tumour has grown to the size of a grain of hemp-seed, it must be cut off, and the wound be anointed with a little fresh butter, or bathed with urine.
3. _Sweating._--There are some females which, during the time of incubation, or while they are on their young, are subject to profuse perspiration; the feathers of the belly are in consequence so wet as to destroy the brood: as soon as this indisposition is perceived the invalid must be washed with salt water, and after a few minutes be plunged into pure water, to wash off the salt, and be dried in the sun as quickly as possible. This operation is to be repeated once or twice a day till recovery; but as relapses are frequent, it is better to separate the female, and not allow her to sit.