230 THE HORSE 



frame, and catches on the top rail of the sash. Iron frames of this shape 

 may be obtained by order of any iron-founder, or they may be made of 

 wood. The glass must be guarded with bars either fixed to the sashes 

 themselves or to the framework. It will be seen in the figure (6) that I 

 have indicated with an arrow the direction which the air inevitably takes 

 as it enters the stable. Sometimes, however, there are . already in the 

 building windows of the ordinary construction; and in that case it will be 

 necessary to introduce ventilators of some shape or other, to admit the 

 external air. The common round tube, with a bend at a right angle 

 downwards on the outside of the wall, is the cheapest form in which this 

 can be done ; but it is very apt to be rendered totally inefficient by being 

 stuffed with hay in cold weather, and left in this state ever afterwards. 

 Several patents have been lately taken out for getting a down-draught by 

 the side of the up-draught tube ; of which Mr. Moir's four-sectioned plan is 

 one of the best. In this a large tube of iron is made to descend from the 

 apex of the roof to the stable ceiling ; and being divided into four tubes 

 by iron plates, which rise above the top, the wind always descends through 

 one or two of these tubes whenever there is the slightest air moving. 

 Unfortunately, however, it happens that when it is most wanted, it is 

 totally inactive namely, in the hot, calm days of summer. Ventilation is 

 always easy enough when there is a wind blowing ; and, indeed, the diffi- 

 culty then is to moderate it ; but it is when there is no air moving that 

 stables become so hot and close. I have known these down-current tubes 

 tried in all sorts of places, including stables, kennels, workrooms, cigar 

 divans, etc. ; but I have always found that, without the power of moderating 

 the down-draught by closing valves placed at bottom of the tubes, they are not 

 only useless in calm weather, but highly dangerous in a wind. Now, horses 

 have not the sense to close valves, when a wind rises in the night, and 

 grooms are absent from 8 o'clock P.M. till 6 A.M., during which time a whole 

 stablef ul of horses may be chilled to an alarming extent. Hence, if adopted, 

 I should never venture* to leave these ventilators open during the night, and 

 this would take away from their efficiency sufficiently to forbid their use. 



Another rather similar plan is the syphon ventilator, a zinc tube from 

 15 in. to 24 in. diameter, divided vertically, and one half carried up higher 

 than the other. The higher or longer half acts by the ascending power 

 of the warm air of the stable as an outlet shaft, while the other or shorter 

 half acts as an inlet of fresh air, the amount of the latter being just 

 sufficient to replace the warm air passing out ; thus a constant, gentle 

 interchange of air is kept up, without draught. The best plan of all, 

 however, is to admit the fresh air by tubes placed against the wall of the 

 passage, communicating with the outer air by a hole in the wall, covered on 

 the outside by a grating. These tubes should have a cross-section of about 

 20 sq. in. to each horse, and their tops should be about 5 ft. 6 in. from the 

 floor, with a regulating valve. The fresh air coming in by these tubes 

 rises straight upwards to the ceiling, and gradually diffuses itself, without 

 causing any draught whatever. 



Having thus provided for the admission of fresh atmospheric air, the 

 next thing to do is to carry it off, when it has been used for the purposes of 

 respiration. As I before remarked, it is not safe to depend upon the wind 

 for this purpose. 



