The flues for carrying off heated vapours, &c., are of two kinds. It has already been stated, that the vitiated air of the rooms is convoyed by apertures just below the ceiling into pipes which find an exit at the top of the house. These flues are made of cylinders of red earthenware, eight or nine inches in diameter. Those by which the smoke of the fires is carried away, are cylinders of fire-brick clay, from two to three inches thick, and from seven to ten inches in diameter. In each fire-place, where the throat of the chimney is contracted over the grate, there is a valve made of rolled iron plate, which fits into a cast-iron seat fixed in the brick-work; when this valve is in its seat, neither soot nor smoke can pass; and when it is thrown back, the passage to the flue is unobstructed. After describing the mortise locks for the doors, and the arrangements of some French windows for opening into a balcony, both of which exhibit ingenious and novel features, Mr. Loudon quotes a letter from Mr. Hay, of Edinburgh, the author of a _Treatise on Harmonious Colouring_, and who superintended the interior decorations of the house. The drawing-rooms are first spoken of thus:--The walls have been prepared with several coats of white lead, grained to imitate morocco leather; on this a pattern of gilded rosettes has been laid, and the whole varnished with copal. Another pattern has then been superadded in flat white, so that the whole has been compared in appearance to a lace-dress over satin and spangles. Mr. Hay says: “There is nothing very much out of my usual practice in the painting done in Sir John Robison’s house in Randolph Crescent, except the walls of the drawing-rooms and staircase. The bed-rooms were done in the usual way; namely, ceilings sized on two coats of oil paint; walls papered with a white embossed satin-ground paper, with small brown sprigs; and the wood-work painted white, and finished with copal varnish. The dining-room and Sir John’s own room were both done in imitation of wainscot, with white ceilings, varnished. The staircase ceilings and cornices painted white and flatted; and the walls and wood-work painted also white, and varnished with copal. The drawing-rooms and ante-rooms were all painted white; the ceilings and cornices, as well as the wood-work, being finished flat, and heightened with gilding. The walls are, as I have already said, rather peculiar in their style of painting. The ground work is rendered regularly uneven by being granulated--by working it over with the point of a dry brush, immediately applying the two last coats of paint. This is partly varnished and partly flat, the flat parts forming large rosettes. Between these rosettes are smaller ones, gilded, not in the base-metal used upon paper-hangings, but in sterling gold leaf. This style of decorative painting, from the great body of paint employed in producing the granulated surface, the copal varnish, and the gold leaf, must