THEOKY OF GROOMING. 83 



when he is in poor condition, or when " drawn fine." 

 The effect of friction applied to the skin, is to draw to 

 the surface an increased amount of blood, from which 

 the glands in question obtain materials for forming their 

 respective fluids. 



The inner layer, or true skin, secretes the outer skin 

 in the form of scales, more or less glued together, 

 according to their distance from the surface. This 

 outer skin lines the openings of the oil and sweat tubes, 

 and surrounds each hair. Its presence affords protec- 

 tion to the skin, and checks the outpouring of the oil 

 and perspiration. Hence, when horses are turned out 

 in the open, without adequate clothing, they should 

 on no account be groomed, which process is intended 

 to remove as much of the outer or scarf-skin as possible, 

 and, by friction, to stimulate the secretion of oil and 

 perspiration. The oil, I may remark, protects the 

 skin from the injurious action of water, and also assists 

 in maintaining the internal temperature of the body 

 by rendering the coat bright and glossy a condition 

 that checks the radiation, as well as the absorption, of 

 heat. Consequently, a horse with a polished skin will 

 not be as liable to be chilled by wet or cold, nor to be 

 as unduly heated by the rays of the sun, as he would 

 be, were his coat dull. This immunity, however, will 

 only last for a few hours, or until the weather affects 

 the hair. 



The skin acts as an assistant to the lungs in giving 

 off carbonic acid gas, and thus aids in purifying the 

 blood. The cold produced by the evaporation of per- 

 spiration materially assists in lowering the temperature 

 of the body to its normal degree, when it has been 



