LESSON II. 



THE NOSTRILS AND LIPS. 



13. — The nostrils are those openings over the 

 muzzle through which the air has to pass on its 

 way to the lungs, and as a horse cannot breathe 

 through his mouth, all the air he breathes 7nust 

 pass throught his nostrils, so that they must be as 

 tvide as possible. 



The nostrils are made up of muscles, which are 

 covered with skin and hair. 



The muscles are for the purpose of regulating 

 the width of the opening. It is plain that when 

 the horse is at rest he needs less air than when 

 walking, trotting, galloping, or drawing a load, 

 and so only breathes about ten or twelves times a 

 minute. In doing so, it is quite plain that the 

 opening of the nostrils need not be so wide, as 

 when at work he breathes three times as quickly. 

 The muscles are thrown into action the moment 

 the horse has to breathe more quickly, and you 

 will have noticed the large, stiff and wide nostrils 

 of a horse that is undergoing severe exertion. 



14. — The opening of. the nostrils when the horse 

 is resting and breathing slowly is a mere chink or 

 slit, but in violent exertion the nostril opening is 

 quite round, and often reminds one of the mouth 

 of that ancient weapon, the blunderbuss. 



