DISEASES OF RESPIRATORY PASSAGES AND ORGANS. 87 



the form of carbonic acid gas, almost as destructive to animaiity 

 as that issuing from its great prototype proves to vegetation. 



The stable atmosphere being pure, and the lungs in working 

 order, the blood is well arterialized, capable of supplying the 

 waste of the animal machine and renovating its tissues. On the 

 other hand, should the atmosphere be impure, it fails to vitalize 

 1he blood. The latter is unfit for the purpose of nutrition, and 

 jiaj be considered a non-supporter of vitality. Hence the need 

 of pure air, the breath of life. 



But are horses always furnished with pure air ? Let the own- 

 ers of unventilated, crowded, filthy, down-cellar and low-roofed 

 stables answer. Let those who have stables in the region of 

 swamp, sewer, and stagnant pools of water answer. In such lo- 

 cations disease and death run riot, and the noble companion of 

 man, instead of being within the ramparts of the science of life, 

 is on the margin of death's domain. He may exist for several 

 days without food and water, yet the consequent result is nothing 

 when compared to that occasioned by breathing an atmosphere 

 highly charged with emanations arising from his own body ex- 

 crements and decomposing bedding. 



A horse is said to consume in the lungs, in the course of twen- 

 /Tour hours, ninety-seven ounces of carbon, furnished by venous 

 blood. In order to perform this feat, he requires 190 cubic feet 

 of oxygen. Now, suppose there are ten horses occupying the sta- 

 ble. They require, in the same time, 1,900 cubic feet of oxygen, 

 and consume 970 ounces of carbon. They are supposed, also, to 

 give out from the lungs a volume of carbonic acid gas equal to 

 that of the oxygen inspired ; and supposing the atmosphere to 

 be saturated with only five per centum of the former, it is a non- 

 supporter of life. Hence, a horse shut up in an unventilated 

 si able must, sooner or later, become the subject of disease. The 

 evil may be postponed, but the day of reckoning is sure and cer- 

 tain. 



Diseases, such as horse-ail, influenza, catarrh, strangles, and 

 glanders, often originate and prevail to an alarming extent in 

 the unventilated stable and pest spot; while in other locations, 

 favorable to the free and full play of vital operations, the favored 

 ones seem to enjoy a remarkable immunity from the prevailing 

 disease, or epizootic. 



Stablemen and husbandmen are often led to remark, that when 



