Thorough cleaning of rooms involves soap, water, sunshine, air, and elbow grease, just as it did before germs were discovered. Cleaning means actually removing dirt and dust, not merely stirring it up to settle again; consequently dry sweeping and dusting are ineffectual. Vacuum cleaning, and sweeping and dusting with damp or "dustless" mops and dusters are good. Deodorants and disinfectants do not take the place of ordinary cleanliness. Dust does not carry living disease germs to an appreciable extent; the fact is now well established that diseases formerly thought to be transmitted by dust or even supposed to travel directly through the air, are carried on tiny particles of moisture and mucus expelled in coughing and sneezing. This mode of transmission is called droplet or spray infection; it is one of the most active agents in spreading certain kinds of communicable diseases. Nevertheless dust in motion is harmful; it irritates the lining membranes of the nose, throat, bronchial tubes, and lungs, even causing tiny wounds through which disease germs enter. Thus tuberculosis is especially prevalent among stone cutters, felt workers, and others engaged in dusty trades. Metallic dust is especially harmful, because it is harder and sharper than dust from organic substances like wool and cotton. Furthermore, presence of dust indicates a low standard of cleanliness. People who tolerate it generally tolerate uncleanliness in other forms, more serious though less apparent. Cleaning would not be so great a problem if most houses were not littered with such dust catchers as carpets, so-called ornaments, carved and upholstered furniture, banners, draperies, and a vast collection of articles that can only be classified as Christmas presents. In actual practice things that are difficult or expensive to clean seldom are cleaned; carpets for example are considered unhygienic, not because they cannot be cleaned, but because they are not. William Morris' advice to exclude from houses all articles not known to be useful or believed to be beautiful would, if followed, add years to the lives of housekeepers. GARBAGE, has little bearing on health, except in so far as it affords a breeding place for flies. If it contains disease germs it may be dangerous, but statistics show that garbage handlers, although they can hardly be called especially careful, are not more subject to sickness than other men of their class. Garbage disposal is chiefly a question of preventing a public nuisance; it is a matter of cleanliness and public decency.