The prejudice against fresh air, especially night air, is a difficult one to overcome. One mother, who kept her children scrupulously clean, could never understand the value of fresh air until a visitor explained to her how air was polluted by the soiled air that we {98} breathed out, just as water was polluted when we washed our hands in it. When the children breathed this soiled air in again it made them "dirty inside"; and this homely statement left such an unpleasant picture in the mother's mind that her rooms were always well ventilated afterward. It is difficult to ventilate a small room without making a draft, but, next to the chimney, the upper sash is the simplest ventilator, and should not be immovable, as it is in many small houses. A board about five inches wide under the lower sash will make a current of air between the upper and lower sashes, and, better still, two pieces of elbow pipe with dampers, fixed in the board, will throw a good current of air upward into the room. Another ventilator can be made by tacking a strip of loosely woven material to the upper sash and to the top of the window-frame. When the upper sash is dropped, the stuff is drawn taut over the opening, and, while permitting air to pass through, breaks the current. Equal in importance with fresh air inside the house is exercise out of doors. I was {99} shocked some years ago to find that, of six Sunday-school boys who went with me on a little trip to our largest city park, five had never been there before. This had not been due to lack of time or money, though they had very little of either; but its sole cause had been lack of enterprise. There is an impatient and popular saying that soap and water are cheap; like many other popular sayings, it is only half true. Personal cleanliness is rather expensive when one takes into account the time, energy, and frequent changes of clothing required to keep the body daintily clean. Visitors should realize this in any effort to introduce a higher standard of personal neatness, and should not be impatient when they do not immediately succeed. Cleanliness and health are so nearly related, however, that the effort is very well worth making. A visitor who hesitated to complain to a mother about her little girl's neglected condition, borrowed the child to spend the day, and brought her home at night sweet, clean, and rosy, with her hair well brushed and curled. The hint was taken. {100}