_Chronic Cough._—It may appear strange to a person unacquainted with the animal economy, that what is taken into the stomach should affect the mucous membrane of the lungs, and that of the larynx, which is the seat of chronic cough. It is in the following manner: when the stomach is distended by hay, and especially if that hay is bad, it is gradually weakened, and rendered incapable of performing its office properly; hence the chyle is crude, and unfit for the purpose it was intended for, that is, forming pure blood. By this imprudent method of feeding them, the blood is rendered impure, and of course all the secretions become so likewise. Thus it is that the bland mucous fluid, formed upon the internal membrane of the wind-pipe and its branches, for the purpose of defending and lubricating it, becomes saline and acrimonious, and a source of constant irritation: hence arises the cough. It is commonly observed, that horses with chronic cough have immoderate appetites both for hay and water; and though people have suspected some connexion between this circumstance and the cough, they have not perceived the entire dependence of the cough upon it, which they might easily have done by a very simple experiment. Let a horse affected with chronic cough be fed moderately upon green food only, and it will generally be found that the chronic cough will gradually go off. But let the horse return to his former method of feeding, and the disease will quickly reappear. There is no occasion to say much on the treatment and prevention of this disorder, when arising from improper feeding. It may be useful, however, to observe, that when the appetite has been depraved, and the digestive power weakened by long continued improper feeding, they cannot be suddenly restored: and it will often require a steady perseverance in a careful system of feeding, and the use of diuretic medicine, in such a way, however, as to keep up only a moderate degree of increased action in the kidneys, without injuring those organs, or affecting the stomach: and this may be accomplished by giving half an ounce of nitre in a little corn twice or three times a day, or the powder described afterwards. If a horse is inclined to eat his litter, he should be muzzled during the night, and in the day time it should be taken from him.