126 CITY MILK SUPPLY 



produce a blotched effect, is unsatisfactory. In placing the windows it 

 should be borne in mind that the barn is lighted both by direct sunlight 

 and by reflected light from the sky. 



Ventilation. Despite the vast amount of study that has been given 

 to ventilation much is yet to be learned about it and about the effect of 

 poor ventilation on health so that dogmatic opinions in these matters are 

 out of place. Researches now under way may considerably modify our 

 present beliefs. The ventilation of dairy barns is highly important. 

 The objects are to provide for: (1) the well-being of the herd; (2) the 

 comfort of the workmen; (3) the removal of odors likely to impart 

 bad flavors to this milk; (4) the carrying off of moisture transpired by 

 the animals, before it has a chance to condense on the barn and rot it. 

 The lighting, ventilating and heating of a barn are related problems, in 

 fact so closely so, that it is generally true that what affects one, in some 

 measure does the others. 



The temperature at which dairy cows should be kept has not been 

 determined ; Eckles is of the opinion that as suitable as any is between 

 40 and 50F., while King thinks it likely that for animals being fed high 

 45 to 50F. is best, that those on a maintenance ration will do better and 

 at lower cost at temperatures between 55 and 65F. To warm barns, 

 reliance is usually placed on the heat given off by animals themselves. 



Ventilation by Windows. Satisfactory ventilation can be secured 

 from windows if there are enough of them and if they are properly disposed ; 

 they should be placed well up the wall usually with the bottoms of the 

 frames at the level of, or somewhat higher than, the backs of the cattle and 

 they should be set flush with the wall that there may be no ledge whereon 

 dust may settle. It is best to have them pivoted at the middle of the sides 

 of the window so that they can be tipped inward leaving openings at the 

 top and bottom. It is almost as good to have them hinged at the bottom 

 so that they can be opened inward at the tops and so admit the air above 

 the animals. Windows that open by sliding sideways or past each other 

 are not so well adapted to dairy barns as other styles are. When window 

 ventilation is practised, the hay and silage chutes serve as outlets for the 

 foul air. 



The King System. The system of ventilating dairy barns most 

 widely used in the United States was introduced in the summer of 1889 

 by King of the University of Wisconsin and is known as the King system. 

 It has the merits of being efficient, simple of construction and not so 

 costly but that most farmers can afford to use it. The King system has 

 been developed on the theory that since carbonic acid gas is the chief 

 impurity in stables, and since this gas is heavier than pure air, foul air is 

 likely to be found in largest, quantities near the floor, therefore, outlets 

 for it are placed near the floor. To be serviceable the system must 

 be installed in a barn that is tight, for the air currents of a loosely built 



