By abuse, however, the word _catarrh_ has come to mean in the minds of a great many people in our time a very serious inflammation of the mucous membranes, almost inevitably progressive and very often resulting in fetid diseased conditions of internal or external mucous membranes, very unpleasant for the patient and his friends and the source of serious complications and _sequelae_. This idea has been fostered sedulously by the advertisers of proprietary remedies and the ingenious exploiters of various modes of treatment. As a result, a great many people who for one reason or another--usually because of some slight increase of secretion in the nose and {33} throat--become convinced they have catarrh begin to feel that they cannot be expected to have as much resistive vitality as others, since they are the subjects of this serious progressive disease. As a matter of fact, very few people in America, especially those living in the northern or eastern States, are without some tendency to mild chronic catarrh. The violent changes of temperature and the damp, dark days predispose to it; but it produces very few symptoms except in certain particularly sensitive individuals whose minds become centered on slight discomforts in the throat and nose and who feel that they must represent some serious and probably progressive condition. As a matter of fact, catarrh has almost nothing of the significance attributed to it so often in magazine and newspaper advertisements. Simple catarrh decreases without producing any serious result, and indeed it is an index of a purely catarrhal condition that there is a complete return to normal. Sometimes microbes are associated with its causation, but when this is so, they are bacteria of mild pathological virulence that do not produce deep changes. As for catarrh developing fetid, foul-smelling discharges or odors, that {34} is out of the question. There are certain affections, notably diphtheria, that may produce such serious changes in the mucous membranes that there will always even long after complete recovery be an unpleasant odorous condition, but it is probable that even in these cases there exists a special form of microbe quite rare in occurrence which produces the state known as _ozena_.