640 The Architectural Review and American Builders' Journal. [April, of the cellar of the building, which is under the corridor. On the south side of this cold air reservoir, are nine, and on the north side are three heating cham- bers, in which are placed box coils of steam pipe, the amount varying accord- ing to the space to be warmed by each. All are closely surrounded by brickwork, the air being admitted to each through openings near the ground, the size of which is regulated by sliding doors. The flues, from these air-chambers, pass into the corridors, and into every pa- tient's room, opening near the floor. Each room has also a ventilating flue, with an aperture near the ceiling, and another near the floor, all of which are regulated by lock registers, so as to be under the control of the officers only. All the warming and ventilating flues pass up in the interior corridor walls, and the latter go into the attic, and there empty into an air-tight duct, which, plas- tered on both sides, gradually enlarges in a greater ratio than the area of the ducts it receives, passes to the central cupola, and thence into the external air. All the flues are made of terra cotta, rather more than three by thirteen inches in the clear, smooth on the inside, with round corners, and built in the centre of the wall. The steam-engine is a horizontal one, of five horse-power ; and the fan, five feet in diameter, is iron, of the Washington pattern, having sixteen blades. It is arranged for a free supply of air, and a free delivery ; and, driven at a moderate speed, can be made to furnish a super- abundance of fresh air at all times. Both are placed under the dining-room, and work noiselessly. The water-closets have a strong down- ward ventilation, through fifty-seven feet of iron pipe and brick flue, leading into the main chimney-stack. Hot water is supplied from a boiler already in use in the eighth ward. This arrangement for heating and ventilation is substantially that adopted at the Department for Males, and which has now been working very satisfactorily for more than nine years ; and is one, the effectiveness of which has been shown by abundant experience. In regard to this subject of heating and ventilating hospitals, there are cer- tain principles and facts that seem to me to be well established. Among these may be mentioned, as prominent, the following: — For many reasons, steam is the best agent for the purpose of heat- ing. Fresh air should be passed over radiating pipes under the rooms, and then admitted into the wards in large quantities, moderately warm in winter, and cool in summer; direct radiation being employed only in a few locations, not constantly used ; and as a help, per- haps, in very severe weather. All flues should be direct, formed in central walls, and made as smooth as possible. No ventilation can be regarded as wortlry of the name, without some forcing power ; and the force that is most available is, either a fan, or a heated chimney-stack, the former being preferable in most in- stances. Unless there are special rea- sons for a contrary course, it is best that the warm air should be admitted near the floor, while the ventilating flues should have openings, under control, both near the ceiling and not far from the floor ; the latter to be used when it is important to save heat. If there realty were any gases too heavy to as- cend, inside of a room, to the opening of the flue, near the ceiling, where the air is necessarily warmer, than at the floor, they would hardly rise in a flue, the temperature of which is gradually be- coming lower, as it ascends. "The diffi- culty can be obviated, only by the in- troduction of heat, either directly or indirectly, into the flue itself, or at some point into which it empties. The fan, however, is the great and best regulator of all this. No matter where the open- ings are made, or even if the flues are cold, the change of air is inevitable ; the intermixture of that driven into the room, with that already there, being
