72 



March ird^ 1891. 



J. H. Greenhill, Esq., President of the Society, in the Chair. 



William Workman, Esq., read a Paper on 

 VENTILATION WITH HEATING. 



The extreme of bad ventilation may be found in some of our 

 cross-channel steamers, where ladies are occasionally carried out 

 in a fainting fit. The sea gets the blame of much of the sickness 

 which should be attributed to foul air. Ventilation requires 

 careful consideration only in cold countries where artificial 

 warmth is required. In summer, and in hot climates, open 

 windows and doors are the rule, and drafts are courted rather 

 than shunned. But a frosty night reverses all this. 



For places of public meeting the open fireplace has long ago 

 been given up, and with it, in general, the small modicum of 

 ventilation secured by its chimney. Hot water pipes, as usually 

 applied, do nothing for ventilation. Sometimes ihey are placed 

 to warm air which may happen to come in at a ventilator, but 

 one rarely or never sees an enclosed column of heated air used 

 either to force in pure air, or extract the foul. The power of a 

 column of heated air is so commonly in use for forcing air 

 through furnaces, as for example in the funnel of a steamer, or 

 in a mill chimney, that it seems to have been forgotten in 

 ventilation. A simple opening in the ceiling of a hall or church, 

 where the temperature is at most 70 to 80 degrees, diminishing 

 to 60 degrees as you descend to the level of the heads of the 

 audience, can have little power to extract air, compared with a 

 much smaller opening, with a tube descending some feet to a 



