The entire specification of this gentleman's improvements is inserted in the Repertory of Arts, and is deserving of perusal by those who are interested in the subject; the leading arrangements may however be understood by the following extract. The plan arranges "the furnace-bars as near as possible under the middle of the boiler, or other vessel's bottom, and to have the aperture or apertures for the escape of the rarefied air and smoke above the door through which the fuel is put in, so that the heated air and gases, by their expansive force and diminished specific gravity, shall prevent the cold air of the atmosphere from penetrating beneath the bottom of the boiler, in order that the cold air admitted at the door where the fuel is introduced, shall, in its passage to the chimney, have no tendency to mix with the heated gases until after they have ceased to act upon such parts of the boiler as are required to be submitted to their action alone. A division of cast plates, extending from the ends of the bars next to the door, separates the grate-room from the ash-hole and air-duct, and prevents any air from passing into the grate-room which does not pass through the ignited fuel." Another peculiarity in Mr. Losh's arrangements, consists in the employment of two fires, which we will call A and B, with a wall between them, which supports the middle of the boiler across its width. Each of these fires has a common flue, which terminates in the chimney, and they communicate with each other by means of an open arch under the partition wall; each fire is supplied alternately with fuel; and the arrangement of the dampers is such, that the gas from the fresh fuel in A shall be compelled to descend, pass under the arch of the division wall, and through the grate bars of the fire B, along with the fresh air that supplies it where the smoke is consumed; the current of heated air from both, thus united, takes its course around the flue into the chimney. By the time that the fuel in A has burned bright, that in B requires replenishing; the dampers are then reversed, which removes the current to the chimney; then the gas from the fresh fuel in B descends under the beforementioned arch up through the grate bars of A, along with the fresh air of supply, and being there ignited, is conducted to the chimney.

In this alternate manner the operation of feeding is continually repeated.