CATARRHAL COLDS (p. l30).--I maintain that it can be proved, with as absolute certainty as any physiological fact admits of being proved, that warm, vitiated indoor air is the cause, and cold outdoor air the best cure, of catarrh....Fresh cold air is a tonic that invigorates the respiratory organs when all other stimulants fail, and, combined with arm exercise and certain dietetic alternatives, it is the best remedy for all disorders of the lungs and upper air passages....A combination of the three specifics,--exercise, abstinence, and fresh air,--will cure the most obstinate cold....Frost is such a powerful disinfectant, that in very cold nights the lung-poisoning atmosphere of few houses can resist its purifying influence; in spite of padded doors, in spite of "weatherstrips" and double windows, it reduces the indoor temperature enough to paralyze the floating disease germs. The penetrative force of a polar night frost exercises that function with such resistless vigor that it defies the preventive measures of human skill; and all Arctic travelers agree that among the natives of Iceland, Greenland, and Labrador pulmonary diseases are actually unknown. Protracted cold weather thus prevents epidemic catarrhs, but during the first thaw Nature succumbs to art: smoldering stove fires add their fumes to the effluvia of the dormitory, tight- fitting doors and windows exclude the means of salvation; superstition triumphs; the lung poison operates, and the next morning a snuffling, coughing, and red-nosed family discuss the cause of their affliction....It is a mistake to suppose that "colds" can be propagated only by direct transmission or the breathing of recently Vitiated air. Catarrh germs, floating in the atmosphere of an ill-ventilated bedroom, may preserve their vitality for weeks after the house has been abandoned; and the next renter of such a place should not move in till wide-open windows and doors and a thorough draught of several days have removed every trace of a "musty" smell.--DR. FELIX L. OSWALD, _Remedies of Nature, Popular Science Monthly, March, 1884_.