Ventilation of Farm Buildings. 351 



from the body and a large portion of it leaves through the 

 lungs and skin in the form of invisible vapor. If the air 

 of a stable or dwelling is not changed with sufficient fre- 

 quency it becomes so damp as to interfere with the proper 

 action of the lungs and skin in this respect, and it is im- 

 portant that the ventilation should be strong enough to 

 prevent the air becoming too damp. 



One of the surest indications of an improperly venti- 

 lated stable is the condensation of moisture on the walls, 

 ceiling and floors. It is sometimes remarked that cement 

 floors, and stone basements are objectionable because they 

 "draw moisture," making the air damp. The truth is the 

 stables are insufficiently ventilated, and the moisture from 

 the animals condenses upon the cement floor and stone 

 walls simply because these happen to be colder. Instead 

 of "drawing" moisture and making the air damp they have 

 exerted exactly the opposite effect by condensing the 

 moisture from the air, leaving it dryer than if the con- 

 densation had not occurred. 



434. Ammonia and Organic Matter Removed from the 

 Lungs. When one passes from the fresh air into an occu- 

 pied stable or room where the air has been rendered im- 

 pure from imperfect ventilation a depressed feeling and 

 offensive odor are recognized and sometimes this effect may 

 be so strong as to produce nausea. When these odors and 

 the odor of ammonia can be detected it is positive proof 

 that the air needs changing more rapidly. 



Some of the organic matter given off from the lungs is 

 strictly poisonous and so much so as to produce death in a 

 few moments. If a live mouse is kept in a sealed pint fruit 

 jar until it is nearly suffocated, as shown by its action, 

 another mouse introduced into this jar will die at once, 

 while the one which vitiated the air may be removed and 

 it will apparently recover. It appears as if the organic 

 principle eliminated from one animal is more poisonous 

 when breathed by another, even of the same kind. 



