^<oEe JAl?aeS I^AV 79 



1252.4 sq. in. Assuming 20 intakes, each would have to be 1252.4 divided 

 by 20 equals 62.7 sq. in. area or about 8 in. x 8 in. square. 



The nominal area of a register or register face should be about 50 per cent 

 greater than given by this computation; actual areas of commercial registers 

 are given in Table 2. 



Cubic Feet of Space per Animal 



It should be distinctly stated that in matters of ventilation it is cubic feet 

 of air rather than cubic feet of space which should be provided, and in the 

 construction of stables, the amount of space need only be so much as is required 

 to permit ample room and freedom for the animals. 



Thirty cows should not be housed in a space much less than 42 x 33 feet, 

 with ceiling 8 feet in the clear. In warm climates there is no objection, except 

 the matter of cost, to high stables, but when it is cold, high ceilings permit 

 warm air to rise so far above the animals as to leave the stable cold at the floor. 



Essentials of a Ventilating Flue 



A good ventilating flue should have all the characteristics of a good 

 chimney. It should be constructed with air-tight walls, so that no air can enter 

 except from the stable. Its interior surfaces must be smooth, and it should rise 

 above the highest portions of the roof, so as to get the full force of the wind. 

 It is better to have it nearly straight, when possible, and it should have an 

 ample cross section area. In case of a slight angle in the flue, the cross section 

 area should be increased, to offset the friction loss. Stronger currents through 

 the ventilators will be secured by making one or more larger ones than where 

 many small ones are provided, and it is usually best to have as few as possible, 

 Def noi leave the impure air in distant parts of the stable. 



