232 MANUAL OF MODERN FARRIERY 



poisoned by the carbon of the blood. These alternate 

 contractions of the chest and lungs constitute what is 

 termed breathing. 



When the horse is subjected to powerful exertion, 

 it is obvious that a more ample supply of uncontamin- 

 ated blood will be required to sustain the energies of 

 life, and violent action of the muscles forces the 

 blood more rapidly through the veins, and hence the 

 quick and deep breathing of the animal when running 

 at speed. Therefore, the more capacious the chest, 

 the greater will be the supply of pure blood, as the 

 lungs will have more room to expand and perform the 

 functions which we have above described. Besides, 

 a capacious chest will fit him for a longer duration of 

 speed. 



Those who are accustomed to hunting or horse- 

 racing, must have frequently witnessed the wonderful 

 relief which loosening the girths have afforded to a 

 horse after a severe gallop. The tightening being 

 removed, permits the chest to expand and contract 

 to a greater extent, and consequently yields a larger 

 portion of purified blood. A very short rest will 

 sufficiently manifest how much the exhausted energies 

 of those organs will recover when the greater expendi- 

 ture is not necessary. 



Even for animals which are not required to possess 

 speed, such as cart, waggon, dray, and farmers' horses, 

 a capacious chest is equally necessary ; for this reason, 

 that in these there is generally a great accumulation 

 of both flesh and fat, which require a large portion of 

 the blood to supply his growth ; consequently, large 

 and ample chests are requisite so as to afford room 

 for the necessary provision of a rapid purification of 

 the contaminated blood. 



Diseases of the lungs are among the worst to 



