1883.] THE VENTILATION OF FABM BUILDINGS. 211 



a room with hot air from outside the room, and bring it in 

 through a register, the hot air is bound to rise from that 

 register to the ceiling, and if you open a hole near the ceil- 

 ing, the hot air goes out, and jou do not get the benefit of 

 your fire. If you want to draw the air out from the bottom 

 of a room, you have got to take it out by a flue at the top of 

 your house. When you have a room heated by a stove, or 

 by an open fire, then you can open a hole at the top of the 

 room, because you have got another source of heat there ; you 

 are using radiated heat ; and such a room as that gets its air 

 from a great many sources ; from cracks in the doors, from 

 cracks in the floor, from cracks in the windows ; and it goes 

 out through the fire-place or up the stove-pipe. 



Now, if you have a stable to ventilate, if you run out your 

 flue at the top, the air is bound to go out at the top, if 

 there is any place for it to get in at the bottom. Run two 

 flues to the top, and the air will come down in one and go up 

 in the other. Any one can try that experiment. Take an 

 ordinary lamp chimney ; cut off a piece of candle half an 

 inch long, light it, and set your lamp-chimney over it ; if 

 there is no air comes in at the bottom, the candle will go out. 

 Now, if you put a partition in that chimney, half-way down, 

 the instant that is done the light will come up, because the 

 air will go down on one side and up on the other. Ventila- 

 tion ought always to be by double shafts, one up and the other 

 down ; but inasmuch as you do not heat your stables by fur- 

 naces, you do not need to have ventilation from the bottom. 



Mr. Webb. I built a barn a few years ago, partially under 

 ground, so that it is open on two sides, and partially open on 

 one side. The barn stands north and south. I had the roof 

 project over about eighteen inches, and put in ventilators on 

 two sides, extending from the roof down to the stable, four 

 feet wide and eighteen inches deep, boarded up so as not to 

 be an obstruction in handling the hay. I put in two on 

 each side, next the partition, with openings about a foot deep 

 under the roof, with sliding doors at the bottom. When the 

 wind blows from the west or northwest there is a very strong 



