THE PKINCIPLES OF YENTILATIOX. 



By KicHARD Peescott, M. E. 



[Read before tlie Albany Institute, December 20, 1881.] 



The systematic ventilation of buildings, by special appliances, is of 

 quite modern date. In the early periods of history, the construction 

 of buildings was of such a character that the most essential features 

 of ventilation were secured of necessity, and as an unintended effect. 

 Thus, until the latter part of the tenth centurv, all rooms that were 

 to be heated were furnished with a hole in the roof, through w^hich the 

 smoke from a fire built on a flat hearth in the middle of the floor 

 escaped. In the sixteenth century chimneys were still rarely used, 

 but from this time their employment rapidly became universal ; they 

 were, however, for the most part, built of sticks covered with a clay 

 plaster. These chimneys Avere always associated with capacious fire- 

 places, containing, on each side of the fire, benches or settees, while 

 from iron bars placed across the throat hung heavy chains from which 

 were suspended the pots and kettles used in the culinary operations. 

 A great volume of air passed up the wide throat of these chimneys 

 from the room, while to take its place streams of air entered through 

 every crack and cranny. In such rooms the air was unquestionably 

 pure enough to satisfy any one, but, save in the chimney corners, it 

 was at the same time too cold for comfort. Indeed, a large room Avitli 

 a large fire-place at one end would become colder the hotter the fire 

 was made. 



That no attention was given to the subject of special appliances for 

 ventilation in the seventeenth and eighteenth centuries is shown by 

 the construction of the public buildings, and particularly the prisons 

 of that time. The well-known investigation of Howard in the latter 

 part of the eighteenth century revealed such an insanitary condition 

 of alfairs in the jails and prisons of England and on the continent that 

 the world stood fairly aghast. Even that profession which should 

 have been foremost in exposing the abuses heaped upon those unfortu- 

 nates, whom either the law or disease had seized, was most conserva- 

 tive in its opinion and senseless in its practice. .For wc read that the 

 physicians in the eighteenth century condemned their fever patients 

 to be immured in rooms made as nearly air-tight as possible, to lie on 

 bods beneath mountains of blankets, to look upon a red counterpane 

 and red curtains, and, as a last refinement of cruelty, to have their 

 small supply of drinking water dyed scarlet. 

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