22 JANUARY 1859, Page 10

The recently introduced snfokeless grate .is a useful improvement. The

coals are placed on an iron tray fixed to the front of the stove at the bottom of the fire, so as to burn the whole of the gases given off. Along the tray, by the action of a right and left handed Archiume- dean screw, joined together about the middle of the grate, the coals are carried under the lighted fuel, which is thus lifted or stirred by the ro- tation of the screw as it deposits fresh coals. No smoke is given off; the combustion of the coals is quicker and more entire, and the amount of heat is greater. The apparatus may be fixed to any grate at a cost of 1/. at most. Furnaces could be fitted with it. If the screw were moved by a lathe band from steam machinery, it would deliver coals into the fire with undeviating regularity, and no need would exist for slacking the draught by opening the furnace door.