The next aim is, to arrange the conveniences of domestic labor so as to save time, and also to render such work less repulsive than it is made by common methods, so that children can be trained to love house-work. And lastly, economy of expense in house-building is sought. These things should be borne in mind in examining the plans of this work.

In the dwelling-house, chap. ii., part ii., Fig. 7, a cast-iron pipe is made in sections, which are to be united, and the whole fastened at top and bottom in the centre of the warm-air flue by ears extending to the bricks, and fastened when the flue is in process of building. Projecting openings to receive the pipes of the furnace, the laundry stove, and two stoves in each story, should be provided in this cast-iron pipe, which must be closed when not in use. A large opening is to be made into the warm-air flue, and through this the kitchen stove-pipe is to pass, and be joined to the cast-iron chimney-pipe. Thus the smoke of the kitchen stove will warm the iron chimney-pipe, and this will warm the air of the flue, causing a current upward, and this current will draw the heat and smells of cooking out of the kitchen into the opening of the warm-air flue. Every room surrounding the chimney has an opening at the top and bottom into the warm-air flue for ventilation, as also have the bath-room and water-closets.

The pure air for rooms on the ground-floor is to be introduced by a wooden conductor one foot square, running under the floor from the front door to the stove-room, with cross branches to the two large rooms. The pure air passes through this, protected outside by wire netting, and delivered inside through registers in each room, as indicated in Fig. 7.

In case open Franklin stoves are used in the large rooms, the pure air from the conductor should enter behind them, and thus be partially warmed. The vitiated air is carried off at the bottom of the room through the open stoves, and also at the top by a register opening into a conductor to the exhausting warm-air shaft, which, it will be remembered, is the square chimney, containing the iron pipe which receives the kitchen stove-pipe. The stove-room receives pure air from the conductor, and sends off impure air and the smells of cooking by a register opening directly into the exhausting shaft; while its hot air and smoke, passing through the iron pipe, heat the air of the shaft, and produce the exhausting current.

The large chambers on the second floor (Fig. 18) have pure air conducted from the stove-room through registers that can be closed if the heat or smells of cooking are unpleasant. The air in the stove-room will always be moist from the water of the stove boiler.

The small chambers have pure air admitted from windows sunk at top half an inch; and the warm, vitiated air is conducted by a register in the ceiling which opens into a conductor to the exhausting warm-air shaft at the centre of the house, as shown in Fig. 23.

The basement or cellar is ventilated by an opening into the exhausting air-shaft, to remove impure air, and a small opening over each glazed door to admit pure air. The doors open out into a "well," or recess, excavated in the earth before the cellar, for the admission of light and air, neatly bricked up and whitewashed. The doors are to be made entirely of strong, thick glass sashes, and this will give light enough for laundry work - the tubs and ironing-table being placed closed to the glazed door. The floor-must be plastered with water-lime, and the walls and ceiling be whitewashed, which will add reflected light to the room. There will thus be no need of other windows, and the house need not be raised above the ground. Several cottages have been built thus, so that the ground-floors and conservatories are nearly on the same level; and all agree that they are pleas-anter than when raised higher.

When a window in any room is sunk at the top, it should have a narrow shelf in front inclined to the opening, so as to keep out the rain. In small chambers for one person, an inch opening is sufficient, and in larger rooms for two persons a two-inch opening is needed. The openings into the exhausting-air flue should vary from eight inches to twelve inches square, or more, according to the number of persons who are to sleep in the room.

The time when ventilation is most difficult is the medium weather in spring and fall, when the air, though damp, is similar in temperature outside and in. Then the warm-air flue is indispensable to proper ventilation. This is especially needed in a room used for school or church purposes.

Every room should have its air regulated not only as to its warmth and purity, but also as to its supply of moisture; and for this purpose will be found very convenient the instrument called the hygrodeik,* which shows at once the temperature and the moisture.

The preceding remarks illustrate the advantages of the cottage plan in respect to healthful ventilation. The economy of the mode of warming next demands attention. In the first place, it should be noted that the chimney being at the centre of the house, no heat is lost by its radiation through outside walls into open air, as is the case with all fire-places and grates that have their backs and flues joined to an outside wall.

In this plan all the radiated heat from the stove serves to warm the walls of adjacent rooms in cold weather; while in the warm season the non-conducting summer casings of the stove described in the next chapter send all the heat either into the exhausting: warm-air shaft or into the central cast-iron pipe. In addition, the sliding doors of the stove-room (which should be only six feet high, meeting the partition coming from the ceiling), can be opened in cool days, and then the heat from the stove would temper the rooms each side of the kitchen. In hot weather they could be kept closed, except when the stove is used, and then opened only for a short time. The Franklin stoves in the large room would give the radiating warmth and cheerful blaze of an open fire, while radiating heat also from all their surfaces. In cold weather the air of the larger chambers could be tempered by registers admitting warm air from the stove-room, which would always be sufficiently moistened by evaporation from the stationary boiler. The conservatories in winter, protected from frost by double sashes, would contribute agreeable moisture to the larger rooms. In case the size of a family required more rooms, another story could be ventilated and warmed by the same mode, with little additional expense.