Besides the openings at the top of the destructor through which the ash pit refuse is fed into the cells, there is a larger opening in each cell, kept covered usually, through which bed mattresses ordered by the medical sanitary office to be destroyed can be put into the cells. These openings are midway between the central openings and the furnace doors, and whatever is put into the cells through these comes into immediate contact with the fire. Advantage is taken of these openings for the destruction of dead animals and diseased meat, and as much as 20 tons in a year have been passed through the destructor. The whole works are roofed over. The lower floor is open on two sides, but the upper one is closed in, with weather boarding at Burmantofts and with corrugated iron at Armley Road. At the former place the works were in some measure experimental, and the platform was constructed of timber, but at Armley Road it is of plate-iron girders, with brick arching, weight being considered advantageous in reducing the vibration of carting heavy loads over it. The cost of each depot has been £4,500, exclusive of land, of which about an acre is required for the destructor, carbonizer, inclined road, weigh office, and space. A supply of water is necessary, a good deal being required for cooling the clinkers. The population of the two districts belonging to these works is about 160,000. The author has no longer any connection with the works described, and for the recent experience of their working he is indebted to Mr. John Newhouse, the superintendent of the sanitary department of the corporation. * * * * * GREEN WOOD. The specific volume of the different constituents of green woods has been estimated by M. Hartig to be as follows, per 1,000 parts: Hard green wood, fiber stuff, 441; water, 247; air, 312. Soft green wood, fiber stuff, 279; water, 317, air, 404. Evergreen wood, fiber stuff, 270; water, 335; air, 395. A certain amount of water--7 or 8 per cent in all--is included with the fiber stuff, showing that about one-third only of the mass of the wood is solid stuff; the remainder is either water or air space. * * * * * THE ARMITAGE HOUSE.