Colds are very seldom caught from the cold, pure air of a draft, but nearly always from the germs, or dirt, in the still, foul air of a tightly closed room.

This fact has swept away the chief objection to the _direct_, or natural, method of ventilating through open windows.
Methods of Ventilation.

Fortunately, as often happens, the simplest and most natural method of ventilation is the best one.

Open the windows, and let the fresh air pour in.

If there be any room which hasn't windows enough in it to ventilate it properly, it is unfit for human occupation, and is seldom properly lighted.