The inhabited rooms should be heated only with open fires, the cellar and halls by radiated heat, or, better, by a hot-air furnace, which shall take its fresh air from above the top of the house and not from the cellar itself or the surface of the earth, where micro-organisms most abound. Let there be no annual house cleaning, but keep it clean all the time, and have it gone through thoroughly at least four times per year. Of course a corner lot is always preferable, but how often it is supposed that the benefit consists alone in a commanding position, in a chance for architectural display, when the greatest boon is the increased opportunity for sunlight. The atmosphere of a room where the sun never shines is never agreeable or healthful. Science has taught us that the sun is the source of all life. It will effect more than tons of disinfectants and chemicals to purge and sweeten the air of a house. Let the building be exposed to the south, and keep shade trees from checking the sun too much. Verandas and broad piazzas often do as much harm as they give pleasure--especially if they are all covered with vines. Be more careful about plumbing than people are wont to be. Do not practice economy by trying to cut down _plumbing_ bills. When a contractor agrees to erect a house, either withhold this part from him or see that he employs the most skilled labor. Ventilation cannot be slighted, for upon it health greatly depends. If you can in any way afford it, use _incandescent electric light_ instead of gas or oil. The reason is a powerful one. An ordinary _gas_ jet destroys as much pure air and oxygen as five men--a good-sized _oil lamp_ equal to three men. Add to this the heat that comes from such methods, and we see the strong advantage of the incandescent electric light. This vitiates no air, gives off no perceptible heat. Though there are stories that electric lights injure the eyes, from careful observation we find that it hurts the eyes of the majority no more than any artificial light. The _Sanitary News_ urges people not to paper or paint the interior walls of houses. Arsenical poisons are used in coloring wall paper. Mold collects in flour paste used in fastening paper to walls, absorbing moisture and germs of disease. Glue also disintegrates, so that any friction removes small particles, to which germs attach and float in the air. Undecorated walls, ugly as they are, the _News_ insists are the only healthy ones to live within. Dr. Cushing, of this city, thus ends his lecture on "Healthful Houses":--