In very cold weather it is equally desirable to close all cracks and chinks against the influx of draughts. Cracks in floors, around the skirting board, or other parts of a room, may be neatly and permanently filled by thoroughly soaking newspapers in paste made of 1 lb. flour, 3 quarts of water, and a tablespoonful of alum, thoroughly boiled and mixed. The mixture will be about as thick as putty, and may be forced into the cracks with a case knife. It will harden like papier-maché. Old windows that do not close tightly may be remedied by smearing the edge on which they close with putty, and that of the sash with chalk, and then closing them as firmly as possible. The putty will fill up the crevices, and the excess pressed out at the sides may be removed with a knife, whilst the chalk prevents adhesion to the sash. A system in very general use is Moore’s patent glass louvre ventilator, consisting of a number of louvres (or slips of glass), which can be opened to any angle up to about 45°, thus always directing the incoming current of air upwards. They are easily regulated and secured by a cord, which when released allows the louvres to close practically air-tight. Moore’s circular glass ventilator, which consists of (usually five) pear-shaped openings, neatly cut in the window square, and fitted with a circular glass cover with corresponding holes working on a centre pivot, are also very effective for admission or extraction of air. Moore’s sliding ventilator consists of oblong vertical holes, with the cover sliding between guides horizontally, the principle being the same as in the circular ventilator, but it is more suited for the top of shop fronts or shallow fanlights. These are all made by J. Moore and Sons, Sekforde Works, St. James’s Walk, Clerkenwell Green, E.C.