Thomas Bond, Popular Science Monthly (1877)
“ People forget that for proper ventilation there must be an inlet and outlet for the air. In bedrooms there is often neither, and if there is a fireplace it is generally closed up. Again, it is a mistake to suppose that foul air goes to the top of a room. Certainly the heated air goes to the top, but the chief impurity, the carbonic acid, falls to the bottom. There is nothing so efficacious in removing the lower strata of air as the ordinary open fireplace, especially if there is a fire burning. The usual defect in ventilation is the want of a proper inlet for the air. ”
