The extraordinary confusion between cold and ventilation, even in the
minds of well educated people, illustrates this. To make a room cold is
by no means necessarily to ventilate it. Nor is it at all necessary, in
order to ventilate a room, to chill it. Yet, if a nurse finds a room
close, she will let out the fire, thereby making it closer, or she will
open the door into a cold room, without a fire, or an open window in it,
by way of improving the ventilation. The safest atmosphere of all for a
patient is a good fire and an open window, excepting in extremes of
temperature. (Yet no nurse can ever be made to understand this.) To
ventilate a small room without draughts of course requires more care
than to ventilate a large one.


[Sidenote: Night air.]

Another extraordinary fallacy is the dread of night air. What air can we
breathe at night but night air? The choice is between pure night air
from without and foul night air from within. Most people prefer the
latter. An unaccountable choice. What will they say if it is proved to
be true that fully one-half of all the disease we suffer from is
occasioned by people sleeping with their windows shut? An open window
most nights in the year can never hurt any one. This is not to say that
light is not necessary for recovery. In great cities, night air is often
the best and purest air to be had in the twenty-four hours. I could
better understand in towns shutting the windows during the day than
during the night, for the sake of the sick. The absence of smoke, the
quiet, all tend to making night the best time for airing the patients.
One of our highest medical authorities on Consumption and Climate has
told me that the air in London is never so good as after ten o'clock at