Ventilation with Heating. 83 



the time, I fancy the Lecturer had the Ulster Hall in his mind, 

 though he did not mention it. 



Prof. FitzGerald said : — I did not hear the beginning of the 

 paper, but the diagrams show pretty clearly what the system of 

 heating the air is. I am very much of opinion that there is 

 sound philosophy in the ordinary practice of putting a fire low 

 down ; for, as the temperature at which the air of a room must 

 be kept is remarkably different in cases where the heating is 

 done by stoves which heat the air, from what it is in a place 

 where it is done by radiation from fireplaces, it is desirable to 

 keep the source of radiation as low as possible, in order not to 

 waste heat in warming up unnecessarily the layer of hot air 

 which, in ordinary rooms, arranges itself in horizontal layers 

 from about the level of the gas brackets, or the top of the doors, 

 upwards. But where the heating is done, not by radiating heat 

 from an open fire to the body, but by warming up the air of 

 the room itself, the air must be raised to a temperature of from 

 70° to 80° Fahr., as experience in Germany, Canada, and the 

 States shows, and must be distributed at,or near, this temperature 

 throughout the rooms. The heating, &c., arrangements must 

 in this case then be governed by considerations as to their 

 capacity for effecting this distribution of the air. As to another 

 point, I have frequently experienced the cascade of cold air 

 which is apt to run down the wall of a church. I think it 

 might be got rid of in many cases by running a somewhat broad 

 shelf, or cornice, along the wall, which would shoot it out 

 horizontally at a level of ten or fifteen feet above the floor. 



Rev. R. Workman said : — I understand my brother to hold 

 that that the warm and pure air goes up where it is useless, whilst 

 the cold and impure air goes down where it is injurious. Now 

 he endeavours to get the warm pure air down to the bottom, 

 and to draw off the impure air before it, or help the warm pure 

 air to force the impure air out. This certainly seems to be a 

 very reasonable way of dealing with the diflBculty, at the same 



