“Every room has a hot air and a foul air flue opening in it, the entrance being protected by an ornamental grate, and the galleries have five or six flues of each kind opening in them, in order that the diffusion may be general. The flues are twelve by twelve, and twelve by nine inches in size. “The pure supplies of air are received into a large reservoir or space in the basement between the walls forming the sides of the galleries above, and in which both kinds of flues are built. This main air channel has an area of at least fifteen feet, and terminates externally in a low tower, fully exposed to the passing air. “The heater is a vertical boiler on the tubular plan, about eight feet in height and thirty inches in diameter. The fuel (anthracite) is placed within the boiler, and that is so placed within the reservoir before named, that only a small part of it, required to receive the fuel, is left outside. “On each side of the reservoir of air, is a construction consisting of six longitudinal chambers one above the other, the whole length of it. The lower three, separated from the upper three by a brick arch and from each other by partitions of wood, are the ventilating channels receiving at intervals the flues from above and finally terminating beneath the exhausting shaft, to be described. “The upper range consists of the three channels for hot air. Both of these ranges are so arranged that a channel answers to a story above, and thus each story of the house has its heating and ventilation entirely independent of any other. “Each hot air channel has a pair of four inch cast iron water pipes connected with spigot joints and iron cement; one end of each comes off the boiler near the top, and the other or return end, enters the boiler on the other side, near its bottom. The hot and cold ends of each pair of pipes are on opposite sides, in order that the average heat at any place where the air is delivered above may be the same. The three pair of pipes receive and return their water, through tubes reduced to two inches diameter, as recommended by Mr. Hood, the highest authority on this class of subjects, and at the same level. The degree of curvature essential in this form of connection, was expected to make a difference in the velocity of the circulating fluid, and consequent temperature at which the water would be found in the different ranges. Practically no material difference is remarked. The radiating pipes cross at the bottom of the cold air reservoir. The air flows in to impinge upon them through arched spaces left in the front of the channels, looking towards the reservoir. Every flue for hot or foul air is commanded by a slide readily approached below.