The most interesting phase of present-day medicine is the open air treatment of respiratory diseases. From a state of mind which confined all patients suffering from diseases of the lungs to close rooms, thoroughly protected from all changes of temperature, there has come a development of medical opinion that insists on the greatest possible amount of fresh air consistent with the absence of drafts and of positive discomfort of high degree to the patient. The results obtained fully justify the practically universal medical agreement in the matter, and the death-rate from consumption has been more materially reduced thereby than by any other form of treatment ever suggested. . . . It is not alone in tuberculosis, but also in other respiratory diseases, that the open air, under what would be usually considered discouraging circumstances, has been found eminently beneficial. In pneumonia, which has of late come to be the worst scourge of life in large cities, it is especially salutary. One distinguished American physician has declared on several occasions that if he were a sufferer from pneumonia, he would prefer to have his bed placed under a tree in the park, even in the depth of winter, than in the best-appointed hospital in the city. Once during the Civil War a snow-storm delayed the transportation of patients and tents, and a number of pneumonia cases were treated in the open field, covered only by army blankets. The mortality of that special epidemic—for nothing is clearer now than that pneumonia is sometimes mildly epidemic—was the lowest of any set of pneumonia cases that occurred during the war. If in these serious illnesses fresh air is of so much benefit, when as a consequence of the lowered state of vitality the healthy reaction especially to cold fresh air might sometimes be missed, it is easy to understand that the same medium is of great importance for the preservation of health. This principle is becoming ever clearer in the minds of sanitarians. The old feeling of aversion to night air, especially because it is supposed to carry all sorts of miasmas with it, is now recognized as absolutely without any good foundation. As has been well said, the only fresh air at night is the night air. Instead of being more dangerous than day air, it is actually more salubrious. Night air in large cities particularly does not contain as a rule so many dust particles as day air, because there is not so much traffic, with movement of truck, carriage, and trolley, to disturb the dust. It is the dust particles to which microbes cling that make air dangerous. The old prejudice with regard to night air was not without an apparently good foundation. Malarial diseases were acquired much more readily at night than during the day. It was almost inevitably fatal for a foreigner to be out on the Roman Campagna at night, though he might visit it with comparative impunity during the day. We now know by absolute demonstration that this was because the malaria-carrying mosquito did its stinging during the night, but especially just after sundown, and this was the time that was considered most dangerous. Properly protected against mosquitoes, however, one who has never had malaria may venture on the Roman Campagna without any danger, and Englishmen have lived there night and day, making the demonstration. As for malaria, so for yellow fever, and it must not be forgotten that so late as but little more than half a century ago yellow fever ravaged the Northern as well as the Southern cities. The disease is mosquito borne, and night is the dangerous time. No wonder our grandfathers, and especially our observant grandmothers, dreaded the night air, and transmitted the tradition of its balefulness. Now this is a thing of the past. If fresh air is good for the ill, it is quite as good, or even better, for the well. The increased incidence of disease in large cities is exactly proportional to the lack of fresh air. Cities are healthiest where population is thinnest, and where the greatest attention is paid to ventilation. There are well-grounded opinions that the recent increase of pneumonia in all our large cities is due to a great extent to the almost hermetical sealing of our houses in the winter time, and to the dryness of artificially heated air, which keeps the lungs in a constant state of irritation, thus rendering them susceptible to infection. For children is this especially true. The lowered resistive vitality of children in asylums and other charitable institutions is largely a matter of restriction of that living in the open air which is so natural and necessary for children. Undoubtedly all the world and its relatives would be benefited in health by a leaf from the book of the modern open air treatment of consumption. The healthy occupations are those which keep people outside most of the time. The ideal occupation for a young man with incipient consumption, in the condition sometimes called threatened with consumption, would be that of motor-man on an electric car, with an open platform, if it were not for the jar and exertion of so frequently applying the brake. Just inasmuch as people can be tempted to live more in the open will the average of health improve. Cold does not cause “colds.” Nansen and his men at the north pole did not suffer from respiratory affections, but several of them were down with grippy “colds” within a short time after their return. Dampness is not an active factor in the production of disease when there is adequate protection of the body by clothes, and when the food is abundant and nutritious, and there is no abuse of stimulants. Old traditions should not be allowed to have weight in the face of modern carefully collated observations. Windows should always be open in sleeping-rooms, no matter how cold or damp the weather; and if care is taken to have dry, abundant bed-clothing, and a warm room to dress in, there not only need be no fear of evil consequences, but the health will always be better, and any tendency, particularly to respiratory diseases, the most frequently fatal affections of this stage of civilization, will surely be obviated.—The Independent.