SBRVICE. Itl 



part of winter arrives. But if they commence in winter, they 

 should be out for only one or two hours at a time ; in good days 

 they may be out longer, no one being able to give a precise rule 

 as to the length of time appropriate, as it varies with the con- 

 dition of the animal, the weather, and the work required. It 

 should shorten with the wetness or coldness of the weather, and 

 the tenderness of the animal. 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 was standing still. After 

 a time he becomes 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, and with many horses several 

 weeks, before the skin can assume activity 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 increased production of heat. 

 To this, however, there are limits. By exposure, gradually 

 increasing in length and frequency, the system may be 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 cannot 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 con- 

 sumes the nutriment that ought to produce vigor for work. 



