Hints for Controlled Breathing
It should go almost without saying that to get the best effects from air you should breathe the purest air obtainable.
Air which is full of dust particles, for instance, may be actually irritating to the delicate mucous membrane that lines the nose, throat, bronchial tubes and air cells of the lungs.
This dust contains particles of organic matter derived from the excrement of horses and dogs, from dried atoms of offal and decaying vegetable matter, or from dried mud impregnated with urine.
Indeed, it is very largely upon these particles that the micro-organisms—arch enemies of mankind as well as of animal kind—are carried on their errand of destruction.
These micro-organisms are most abundant in the air of inhabited rooms—and the more people in the room the greater the number of microbes present.
So don’t be afraid of open windows—day or night. Remember Florence Nightingale’s quaint observation, “Windows are made to be opened.”