The wash enters, through the hopper, D, and the valve, z, a long boiler, B, which is heated by the furnace, F, through the intermedium of a waterbath, w. An agitator, E, moves the mass slowly to the other extremity of the boiler, from whence it makes its exit in the form of dust. To the frame, E, are fixed the scrapers, b, and the interrupted pieces, a, in front of which are the hinged valves, c. In the motion of the pieces, a, from right to left, these valves free the apertures thereof and allow the wash to pass, while in the motion from left to right the apertures are closed and the valves push the mass to be evaporated before them. From any motor whatever, the frame, E, receives a double to and fro motion in a horizontal and vertical direction, the latter of which is produced by the rods, f, which are provided at their lower, forked extremity with rollers, e, over which passes the piece, d, that supports the frame, E. At their upper part the rods, f, pass through the side of the boiler, through the intermedium of stuffing boxes, and are connected by their upper extremities, through a link, with levers, g, that revolve around the point, h. A cam shaft, M, communicates a temporary, alternately rising and descending motion to the levers, g, and the rods f. The same shaft, M, opens and closes the valve, z, of the hopper, D, and thus regulates the entrance of the wash into the boiler. The frame, E, receives its horizontal to and fro motion from the rod, l, which traverses a stuffing-box and is moved by a crank on an eccentric, m. The material in powder derived from the evaporation of the wash is stored at the extremity of the apparatus into a lixiviating vessel, G, provided with a stirrer, H. The salts and other analogous matters are dissolved, and the residuum, which constitutes a carbonaceous mass, is forced out of the apparatus, while the solution passes directly to the refinery, where it is evaporated. [Illustration: APPARATUS FOR THE EVAPORATION OF ORGANIC LIQUIDS.] In manufactories where no refining is done, the crude potassa in powder is pushed on to a prolongation of the apparatus which is cooled by means of water, and is removed from time to time with shovels by the workmen, so that the orifice of the boiler remains constantly covered externally by the mass, and that the air cannot re-enter the apparatus. The gases disengaged during the operation pass into a cooler, where they condense into a liquid which contains ammonia and methylamine. The non-condensable part of the gases is burned in the furnace of the manufactory. * * * * * IMPROVED LEVELING MACHINE. In the American Court of the Inventions Exhibition, London, we find a leveling machine for sheet metals exhibited by Mr. J.W. Britton, of Cleveland, Ohio, and which we illustrate.