THE WARMING AND VENTILATION. The arrangements for warming and ventilating the High School Building are similar to those planned by Charles B. Richards, civil engineer, of Philadelphia, and applied by Mr. Keller to the State Hospital for the Insane, at Middletown. The steam is supplied by boilers placed outside the building; the sewerage gases can in no way find access to the ventilating flues, and the water closets are ventilated by an independent system. The building is two stories high, with an attic and basement. On the first floor there are seven class-rooms, and on the second floor there are four class-rooms and a large assembly hall. Each classroom contains between fifty and sixty scholars, and it is designed to ventilate each room with a supply of fresh air amounting to 30 cubic feet of air per minute for each scholar. To accomplish this the arrangement for the introduction of air is to admit the fresh air after it has been adequately heated at an opening placed at the back or inner wall of each room, remote from the windows and cool outside walls, the effective cooling average surface of which-windows and walls-being as near equidistant from the point of admission of warm air as the form of the room will permit. This opening for the admission of warm air is placed about seven feet above the floor, so that the incoming current is not thrown upon any person standing near the opening. The direction of inflow will be made toward the windows, at the same time rising toward the ceiling. The warm air receives guid. ance from the outlet of the flue, and is also induced by the action of the windows and outside walls in demanding a greater or less supply of air for the downward currents against or near them. The provision for the extraction of air is to withdraw the cooler and partially vitiated air from the surface of the floor through openings to flues placed as near the inner walls of the rooms as practicable. The cold sheet of air traversing the panes of glass is intercepted before it falls or follows the wall to the floor by a broad and level window seat which throws the air inward to mingle with the warmer air of the room. Supplementary steam pipes are run under the windows the whole width of the room, to counteract the cooling effect of the glass. Each room by itself and of itself, together with its inlet and outlet flues, is considered as one shaft or chimney. Such a shaft, starting as a flue at A, as shown in Diagram I, from an air chamber B, at the ground level, and having a small or limited sectional area, rises some height to an enlargement C, the room itself, the sectional area of the room being so out of proportion to that of the flue that the velocity of flow through it or the eddies occasioned by the flow may be imperceptible; and thence again to another flue D of limited section rising to and above the roof. B AIR CRAMACA Diagram 1. In order to make this "chimney" to draw, heat is supplied by radiators at the bottom, and during mild weather is further assisted by heat supplied to the outgoing flue above the room, either by gas jets or coils of steam pipe, as may be most suitable. THE APPLICATION. The High School is 236 feet long, running north and south, and averages 100 feet in width. It is divided almost in the middle by a twelve-foot wide corridor extending the whole length of the building from north to south. The different class-rooms, library, recitation-rooms, etc., open into this corridor on the right and left, so that the side walls of the corridors are also the inner walls to all the rooms. This arrangement admits of the introduction of the warm air to the different rooms of the building, at the end of the room farthest from the windows, by devoting the corridor in the basement for its whole length to an enclosed fresh-air duct, communicating by independent hot-air flues with each room. The fresh air is taken in at both ends, as shown on basement plan. (Plate I.) The fresh air passes through primary radiators placed at the ends of corridor, which temper the air before it comes in contact with the radiators placed at the mouth of each hot-air flue in the basement. Each of these hot-air flues is provided with an independent radiator through which the fresh air in the corridor passes and is warmed before it enters the flue to supply fresh warm air to the room above. |