The constant irritation of the throat occurring in mouth-breathers weakens the natural resistance against such diseases as acute tonsilitis, scarlet fever, and diphtheria, so that they are especially subject to these diseases. But these are not the only ailments to which the mouth-breather is liable, for earache and deafness naturally follow the catarrh, owing to obstruction of the Eustachian tubes (see Earache, p. 40, and Deafness, p. 38). Deformity of the chest is another result of obstruction to nose-breathing, the common form being the "pigeon breast," where the breastbone is unduly prominent. The voice is altered so that the patient, as the saying goes, "talks through the nose," although, in reality, nasal resonance is reduced and difficulty is experienced in pronouncing N and M correctly, while stuttering is not uncommon. Nasal obstruction leads to poor nutrition, and hence children with adenoids and enlarged tonsils are apt to be puny and weakly specimens. =Treatment.=--The treatment is purely surgical in all cases of nasal obstruction: removal of the adenoid growths, enlarged tonsils, and polypi, straightening the displaced nasal septum, and burning the thickened mucous lining obstructing the air passages in the nose. None of the operations are dangerous if skillfully performed, and should be generally done, even in the case of delicate children, as the very means of overcoming this delicacy. The after treatment is not unimportant, consisting in the use of simple generous diet, as plenty of milk, bread and butter, green vegetables and fresh meat, and the avoidance of pastries, sweets, fried food, pork, salt fish and salt meats, also the roots, as parsnips, turnips, carrots and beets, and tea and coffee. Life in the open air, emulsion of cod-liver oil, daily sponging with cold water while the patient stands in warm water, followed by vigorous rubbing, will all assist the return to health. =SORE MOUTH; INFLAMMATION OF THE MOUTH.=--There are various forms of inflammation of the mouth, generally dependent upon the entrance of germs, associated with indigestion or general weakness following some fever or other disease. Unclean nipples of the mother or of the bottle, or unclean bottles, allow entrance of germs, and are frequent causes. Irritation of a sharp tooth, or from rubbing the gum, or from too vigorous cleansing of the mouth, may start the disease. Some chemicals, especially mercury improperly prescribed, produce the disease. The germs may gain admission in impure milk in some cases. Inflammation of the mouth is essentially a children's disease, only the ulcerated form being common in adults.