VENTILATION. 



33 



tilating shaft, which is admissible to all or every variety 

 of stable, without occupying much space or costing a great 

 deal of money for the material and construction ; and, 

 moreover, its utility rests upon true principles of ventila- 

 tion by its situation and capacity to carry off the foul air, 



presuming always that sufficient air is admitted into the 

 stable nearer the ground by the doors and windows, and 

 registers placed in the walls. These registers or louvres are 

 made on the same principle as those in dwellings where fur- 

 naces are used. Instead of a multiplicity of tubes in a stable 

 corresponding to the number of horses, one will answer, if 

 of sufficient capacity and properly placed, with its mouth 



