of the outdoor world and the vitiated, sickening night-air of your sweltering dormitories."
But what the self-torturers are really afraid of is a "draught;" in other words, air in motion. Perceptible currents of air, no matter how pure, no matter how passionately welcomed by the miasma-clogged lungs, they dread as messengers of death. Their fear of night-air is founded chiefly on the circumstance that the cooling of the atmosphere generates air-currents within a few hours after the sunset even of the sultriest day. So they close their bedroom windows or nail them down; they invent double window-sashes and "weather-strips," to exclude the slightest breath of life-air.
And yet the sanitary value of fresh air is generally proportioned to the persistency of its currents. Air in motion removes the impurities of the atmosphere. It renews the supply of oxygen. Its ministrations attend both to the disinfection and the nourishment of the respiratory organs. The sanitary difference between fresh air in motion and stagnant indoor air is that between the pure water of a running fountain and the festering slime of a cesspool.
The comparatively low temperature of night-
