CHAPTER III. 

 STABLE HYGIENE CARE OF THE SICK AND INJURED. 



STABLE HYGIENE. 



131. Ventilation. The object of ventilation is to supply pure 

 air to the lungs, to dilute and remove the products of respiration, 

 and the ordor and gases arising from the fluid and solid excrements 

 which have been evacuated by the occupants of the building. 



132. Composition of air. Pure air consists of: 



Parts. 



Oxygen 2, 096 



Nitrogen 7, 900 



Carbonic acid ...... 4 



Total 10,000 



It also contains a small quantity of watery vapor. 



Oxygen is the chief useful part of the air for purifying the blood. 

 Nitrogen dilutes the oxygen and renders it respirable. The amount 

 of carbonic acid is very small, but if it rises beyond 6 parts in 10,000 

 the air is impure and unfit to breathe. 



Air is rendered impure by the respiration of men and animals, its 

 carbonic acid and watery vapor are increased, its oxygen diminished, 

 and a proportion of organic matter added to it. So long as respira- 

 tion is occurring in the open air these impurities are gotten rid of as 

 fast as they are formed, but in the air of buildings it is different, for 

 here they accumulate unless means are at hand for getting rid of 

 them. The employment of such means is known as ventilation. 



133. Testing the ventilation. The proper time to test the 

 ventilation is in the morning before the doors are opened. If on 

 entering the stable a sense of stuffiness is detected, the ventilation 

 is defective, and more air must be supplied. . 



134. Draft and chill. A draft is a current of air passing through 

 a confined space, such as a window or door, at such a rate as to pro- 

 duce a feeling of cold when it strikes the skin. The effect of such a 

 draft on a warm skin is to drive the blood into the internal organs 

 and produce chill and shivering. Tying animals in a draft must 

 therefore be carefully avoided. 



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