24 FIRST PRINCIPLES. 



supply of blood for a considerable time, the blood, if suddenly 

 restored to them, appears to act more or less as an irritant to 

 their walls ; the only safe way of overcoming the difficulty 

 being to gradually accustom them to its return. Thus, in 

 frost-bite, if the blood, after having been driven away by cold, 

 is allowed to suddenly return, violent inflammation, which 

 may be followed by death of the part, will ensue. Here, the 

 proper treatment will be the adoption of means, such as 

 rubbing with snow, which will permit of only a very gradual 

 return of a full supply of blood. The usual effect, however, 

 of cold is, as we have seen, to produce anaemia (not inflamma- 

 tion), and the special danger to be feared is congestion of the 

 deep-lying parts. Hence, when horses are over-heated from 

 exertion, we should have them walked about, or should have 

 vigorous and prolonged friction applied to their skin by two 

 or more strappers to each animal, so that the healthy conges- 

 tion of the muscles of the limbs and of the superficial muscles 

 of breathing may not be relieved too quickly ; and we should 

 stimulate the sweat-glands by giving a liberal supply of water. 

 Neglect of these precautions is a frequent cause of congestion of 

 the lungs, especially among unfit hunters which have to return 

 by rail to their stable after having been out with the hounds. 

 In a typical case of this kind, when the animal is pulled up and 

 is freed from his burden, the blood vessels of his limbs and of 

 the surface of his body are filled with blood which has been 

 brought in response to the stimulus of exercise. This healthy 

 congestion soon becomes changed to anaemia by cold air, and 

 especially by a cold wind acting on a horse which is standing 

 still in a railway horse box, or perhaps in a more exposed 

 situation, and the internal organs now become congested. 

 Probably, when the horse gets into his stable, the amount of 

 grooming he receives will not exceed that which is sufficient 

 to put his coat "straight " ; he gets very little water ; and we 

 need not be surprised if by bedding-down time he is 



