AIR AND VENTILATION 



105 



ceiling and become warmed before it settles to the floor. The 

 construction of the foul air flues is of importance, as faulty con- 

 struction has led to failure in the system. They should be as 

 straight as possible, as every turn or bend greatly reduces the carry- 

 ing capacity by increasing the friction of the moving air on the flue. 

 A good ventilating flue should have the same qualities as a good 



FIG. 46. The King system of ventilating cow barns as adopted in America. 

 (By permission from the Wisconsin Experiment Station Bulletin 164.) 



chimney. It should rise above the highest part of the roof, so as 

 to receive the full force of the wind. Where only one flue is used 

 it should be placed as near the centre of the building as possible. 

 Doors and windows must fit well. Foul air flues should be air- 

 tight and non-conductors of heat and cold. The lower opening 

 should be about 1 foot above the floor level, and with as few bends 

 as possible pass up to a height of at least 25 feet, and should always 

 be 2 or 3 feet above the ridge of the roof or of any adjoining roof. 



The King system of ventilation is unnecessary with the tem- 

 perate climate of Great Britain. 



TESTING THE EFFICIENCY OF THE VENTILATION. A veterinary 

 inspector may be called upon to give an opinion as to the efficiency 

 of the ventilation of a cow-house, stable or other animal habitation. 

 Local Authorities may require cow-keepers, under powers vested 

 in them through the Dairies, Cow-sheds and Milk Shops Order, to 

 make adequate provision for lighting and ventilation of cow byres. 



No specific requirements are stated except that the total cubic 

 air-space per cow may be defined, viz., not less than 800 cubic feet 

 per head, but the ventilation and lighting must be to the satis- 

 faction of the Local Authority. 



