directly into the fresh air. In most private houses it is generally possible to arrange for those to whom an open window at night is a forbidden luxury, that they should sleep with their door open. A curtain, or screen, or even the open door itself will ensure the privacy in which we all like to do our sleeping, but there should then be some window open on an upper landing, day and night, in all weathers. Believe me, there are few nights, even in our rigorous climate, where this would be an impossibility. Of course common sense must be the guide in laying down such rules. No one would willingly admit a fog or storm of driving wind and rain into their house, but of a night when the atmosphere is so exceptionally disturbed it is sure to force its way in at every cranny, and keep the rooms fresh and sweet without the necessity of admitting a large body of air by an open window.
Supposing then that the laws of ventilation are understood and acted upon, and that certain other sanitary rules are carried out which need not be insisted upon here,—such as that no soiled clothes shall ever, upon any pretence, be kept in a bedroom,—then we come to the next cause of want of freshness in a sleeping-room:—Old walls. People do not half enough realise, though it must be admitted