1150. _To make durable Barn-floors._--A durable barn-floor may be made of well-burnt polished brick on edge, placed in the herring-bone form, on a pavement of stone three inches and a half in thickness; or oaken plank two inches and a half in thickness; or even of well-tempered indurated loam, of a proper substance, not less than eight inches, and laid upon dry materials or bottom. Any of them will make a durable barn-floor, provided it is kept free from wet, wagon-wheels, and horses' feet. The best threshing-floor for small farms of 150 acres is made of sound plank. In large farms (say 300 acres and upwards) the threshing machine should supersede the flail. 1151. _The Virtues of Poplar Wood for the Flooring of Granaries._--The Lombard poplar is recommended as a timber adapted for flooring granaries, which is said to prevent the destruction of corn by weevils and insects. Poplar wood will not easily take fire. 1152. _Improved Ventilators for Rooms._--Different methods are adopted for ventilating, or changing the air of rooms.--Thus: Mr. Tid admitted fresh air into a room by taking out the middle upper sash pane of glass, and fixing in its place a frame box, with a round hole in its middle, about six or seven inches diameter, in which hole is fixed, behind each other, a set of sails, of very thin, broad copper plates, which spread over and cover the circular hole, so as to make the air, which enters the room, and turning round these sails, to spread round in thin sheets sideway, and so not to incommode persons by blowing directly upon them, as it would do if it were not hindered by the sails. This well-known contrivance has generally been employed in public buildings, but is very disagreeable in good rooms; instead, of it, therefore, the late Mr. Whitehurst substituted another, which was, to open a small square or rectangular hole, in the party wall of the room, in the upper part, near the ceiling, at a corner or part distant from the fire; before it he placed a thin piece of metal, or pasteboard, &c., attached to the wall in its lower part, just before the hole, but declining from it upwards, so as to give the air that enters by the hole a direction upwards against the ceiling, along which it sweeps, and disperses itself through the room, without blowing in a current against any person. This method is very useful to cure smoky chimneys, by thus admitting, conveniently, fresh air. A picture, placed before the hole, prevents the sight of it from disfiguring the room. 1153. _Approved Method of removing Bees._--Set the hive where there is only a glimmering light; turn it up; the queen first makes her appearance; once in possession of her, you are master of all the rest; put her into an empty hive, whither she will be followed by the other bees.