Never go out-of-doors when it's windy, or rainy, or wet underfoot, or cold, or hot, or looks as if it was going to be any of these.
Be just as intimate and affectionate as possible with every one you know who has a cold. Don't neglect them on any account.
CHAPTER V
ADENOIDS, OR MOUTH-BREATHING: THEIR CAUSE AND THEIR CONSEQUENCES
In all ages it has been accounted a virtue to keep your mouth shut—chiefly, of course, upon moral or prudential grounds, for fear of what might issue from it if opened. Then came physiology to back up the maxim, on the ground that the open mouth was also dangerous on account of what might be inhaled into it. Oddly enough, in this instance, both morality and science have been beside the mark to the degree that they have been mistaking a symptom for a cause. This has led us to absurd and injurious extremes in both cases. On the moral and prudential side it has led to such outrageous exaggerations as the well-known and oft-quoted proverb, "Speech is silver, but silence is golden." Articulate speech, the chiefest triumph and highest single accomplishment of the human species, the handmaid of thought and the instrument of progress, is actually rated below silence, the attribute of the clod and of the dumb brute, the easy refuge of cowardice and of stupidity.
Easily eight-tenths of all speech is informing, educative, helpful in some modest degree; while fully that proportion of silence is due to lack of ideas, cowardice, or designs that can flourish only in darkness. It is not the abundance of words, but the scarcity of ideas, that makes us flee from "the plugless word-spout" and avoid the chatterbox.
Similarly, upon the physical side, because children who breathe through the mouth are apt to have a vacant expression, to be stupid and inattentive, undersized, pigeon-breasted, with short upper lip and crowded teeth, we have leaped to the conclusion that it is a fearsome and dangerous thing to breathe through your mouth. All sorts of stories are told about the dangerousness of breathing frosty air directly into the lungs. Invalids shut themselves scrupulously indoors for weeks and even months at a stretch, for fear of the terrible results of a "blast of raw air" striking into their bronchial tubes. All sorts of absurd instruments of torture, in the form of "respirators" to tie over the mouth and nose and "keep out the fog," are invented, and those who have the slightest tendency to bronchial or lung disturbances are warned upon pain of their life to wrap up their mouths whenever they go out-of-doors.
As a matter of fact, there is exceedingly little evidence to show that pure, fresh, open air at any reasonable temperature and humidity ever did harm when inhaled directly into the lungs. In fact, a considerable proportion of us, when swinging along at a lively gait on the country roads, or playing tennis or football, or engaged in any form of active sport, will be found to keep our lips parted and to inhale from a sixth to a third of our breath in this way, and with no injurious results whatever. Nine-tenths of all the maladies believed to be due to breathing even the coldest and rawest of air are now known to be due to invading germs.
Nevertheless, mouth-breathing in all ages has been regarded as a bad habit, and with good reason. It was only about thirty years ago that we began to find out why. A Danish throat surgeon, William Meyer, whose death occurred only a few months ago, discovered, in studying a number of children who were affected with mouth-breathing, that in all of them were present in the roof of the throat curious spongy growths, which blocked up the posterior opening of the nostrils. As this mass was made up of a number of smaller lobules, and the tissue appeared to be like that of a lymphatic gland, or "kernel," the name "adenoids" (gland-like) was given to them. Later they were termed post-nasal growths, from the fact that they lay just behind the rear opening of the nostrils; and these two names are used interchangeably. Our knowledge has spread and broadened from this starting-point, until we now know that adenoids are the chief, yes, almost the sole primary cause, not merely of mouth-breathing, but of at least two-thirds of the injurious effects which have been attributed to this habit.