infectant 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 "weather-strips" 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 catarrh; but during the first thaw Nature succumbs to art; smouldering 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 suffering, coughing, and red-nosed family discuss the cause of their affliction. "Taken cold"—that much they premise, without a debate. But where and when? Last evening, probably, when the warm south wind tempted them to open the window for a moment. Or, "when those visitors kept chatting on the porch and a drop of water from the thawing roof
