“ People don't know what a gain there is to health by living in cities, the best parts of them of course, for we know too well what the worst parts are. ”
 Oliver Wendell Holmes Sr., The Poet at the Breakfast-Table (1872). copy citation

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“good solid brick walls behind her, good sheets of plate-glass, with the sun shining warm through them, in front of her, and you have put her in the condition of the pine-apple, from the land of which, and not from that of the other kind of pine, her race started on its travels. People don't know what a gain there is to health by living in cities, the best parts of them of course, for we know too well what the worst parts are. In the first place you get rid of the noxious emanations which poison so many country localities with typhoid fever and dysentery, not wholly rid of them, of course, but to a surprising degree. Let me tell you a doctor's story.” source