The work of some horses exposes them much to the weather. Those employed in. street-coaches, in the carriages of medical men, all those that have to stand in the weather, can never do so with safety Dili they have been seasoned. In the cold rainy months, many are destroyed; and many more endangered by injudicious exposure. Wet weather is the most pernicious, yet it is not the rain alone that does the mischief. If the horse be kept in motion, and afterward perfectly and quickly dried, or be kept in motion till dry, he suffers no injury. His coat may be bleached till it is like a dead fur; but the horse does not catch cold. If allowed to stand at rest with his coat drenched in rain, the surface of the body rapidly loses its heat. There is no stimulus to the formation of heat; the blood circulates slowly, accumulates internally, and oppresses vital organs, especially the lungs. The legs become excessively cold and benumbed; the horse can hardly use them, and, when put in motion, he strikes one against another. Exposure, when it deprives the body of heat in this way, is a fertile source of inflamed lungs, of thoracic influenza, catarrh, and founder.

When the skin is wet, or the air very cold, the horse should, if possible, be kept in motion, which will preserve him, however little he may have been accustomed to exposure.

Horses that have been kept in warm stables, and never out but in genial weather, are in most danger. If they can not be kept in constant motion, they must be prepared before they are exposed. If they commence work in summer or early in autumn, they will be fully inured to the weather before the worst part of winter arrives. But if they commence at this trying period, they should be out only one or two hours at a time : on good days they may be longer. No precise rule can be given. The length of time for which a horse may be exposed without danger, varies with his condition, the weather, and the work. It should shorten with the wetness or coldness of the weather, and the tenderness of the horse. If he must run rapidly from one place to another, and wait perhaps half an hour at each, he is in more danger than if the pace were slower, and the time of waiting shorter; and if moved about constantly, or every ten minutes, he suffers less injury than if he were standing still. After a time the horse is inured to exposure, and may be safely trusted in the severest weather.

Repeated and continued application of cold to the surface of the body stimulates the skin to produce an extra supply of heat. The exposure of two or three days is not sufficient to rouse the skin to this effort. It is always throwing off a large quantity of heat; but it is several days, with many horses it is several weeks before the skin can assume activiry sufficient to meet the demands of a cold or wet atmosphere Ultimately it becomes so vigorous that the application of cold whether wet or dry, is almost instantly followed by an in creased production of heat. To this there are limits. By exposure, gradually increasing in length and frequency, the system may become able to maintain the temperature at a comfortable warmth for three or four successive hours, even when the horse is standing at rest in wet or cold. But he can not endure this beyond a certain point. Exhaustion and emaciation succeed, in spite of all the food the horse can eat. The formation of so much heat consumes the nutriment that ought to produce vigor for work.

Hence, working horses kept very much in very cold stables are always lean and dull.

It is chiefly the horses that have to stand in the weather which require preparation for exposure. Bleeding, purging, and other means, which debilitate or emaciate, are never necessary in this process. Hunting, stage-coach, and cart horses, seldom require any preparation for exposure. They are in motion from the time of leaving till the time of returning to the stable. They just require to be well and quickly dried when wet.