22,547. Hertzog, L. Oct. 19. Gas-producers.- Relates to a process and apparatus for producing gas for power and other purposes, in which the gases from the generator, in addition to being used for the generation of steam for supplying the generator, are used also to heat the generator by passing them through the hollow casing thereof, and iu which the supply of water to the steam generator is automatically regulated in accordance with the temperature of the gas as it leaves the generator, thus increasing the percentage of hydrogen in the gas. The invention is particularly applicable to suction generators for supplying gas engines, and may be applied also to primary generators for supplying furnaces. A shaft a, Fig. 1, surrounded with fireproof material, is fed with fuel by a hopper f, which forms part of a cover-plate. Above the shaft a is placed a steam generator r, having tubes s, and a central tube through which the fuel is fed. The gases produced pass up through the tubes s, after which they pass, by means of the spaces 3 and 2, surrounding the generator and boiler, away to the pipes 8 or 9 according to the position of the valve shown. When the fire upon the grate e is first lit, a fan v is started, and air is forced through the valve w, which at the same time shuts off communication between the channel 4 and the chamber 6, and passes up through the grate. The smoke and gases now evolved are led away to the flue 8, until the fuel is incandescent, after which the chamber 2 is put in communication with the outlet 9 and the fan is stopped. Air enters through the openings c, passes up between the casings l and m and, after being heated by the hot cylinder m, enters the steam generator r through the openings 5. The steam and air pass, as shown in Fig. 2, down the channel 4 and then up through the firegrate, and are decomposed by passing up through the fuel in the shaft a, and the resulting hot gases, after heating the steam generator r, are led away down the space 2, and through the pipe 9 to the purifiers. To regulate the supply of water to the steam generator r, an air cylinder g, provided with a diaphragm y, is placed in one of the tubes s. The hot gases cause the air in the cylinder g to expand and the diaphragm y to rise and, by means of a lever connected to it, open the water supply cock, according to the degree of heat of the generator gases. In place of the membrane y, a piston working in a cylinder containing mercury or ether, and connected to the water-supply cock, by means of a rod passing through the cover of the cylinder, is caused to move by the expansion of the air in the reservoir g, which is connected to the cylinder by a small pipe. Instead of causing the air and steam to pass to the channel 4 as shown in Fig. 2, they may be led to it as shown in Fig. 3, so that the air is more highly heated before it enters. In order that a larger heating-surface may be obtained, the cylinder m, n and the steam generator r may be corrugated.