Mr. Edward N. Dickerson's Apparatus (Figs. 8 to 13).--Mr. Dickerson, of New York in June, 1895, patented several arrangements permitting of automatically regulating the production of acetylene in measure as it is consumed. In the apparatus represented in Fig. 8 the water is led from a sufficiently high reservoir, A, through the pipe, B, into the gas generator, D, and over the carbide, C, placed upon a grate, O. The acetylene forms when the water reaches the carbide, and its disengagement ceases when the pressure forces the water back. The gas passes through the intermedium of a cock, e, into the pipe, W, provided with a cock, Z, into the automatic regulator, G, and then into the gasometer, P R. Between the regulator, G, and the gasometer, Mr. Dickerson interposes an arrangement consisting of an engine, H, actuating an air pump, K, through the pressure of the gas when it is desired to introduce a mixture of acetylene and air into the gasometer. This arrangement is evidently useless when it is desired to collect the acetylene alone. The gas upon making its exit from the gasometer flows through the pipe, T, to the burners, V. [Illustration: FIG. 8.--DICKERSON ACETYLENE APPARATUS, WITH AUTOMATIC REGULATION] When the holder, R, is filled, the cord or chain, a, passing over the pulley, b, revolves the sector, c, until the pin, g, meets the counterpoised lever, d, of the stopcock, e. In the return of the chain, the other pin, o, carries the lever back to the position shown in the figure. The gas generator, D, is provided with a discharge cock, E, and a charging aperture, m. Figs. 9 to 13 show another of Mr. Dickerson's apparatus that permits of an intermittent automatic distribution either of the water upon the carbide or of the carbide in the water in regulating such distribution through the displacement of the holder of a gasometer that collects the excess of gas necessary for the consumption. [Illustration: FIG. 9.--DICKERSON ACETYLENE APPARATUS, PERMITTING OF THE AUTOMATIC INTERMITTENT DISTRIBUTION OF WATER UPON CARBIDE OF CALCIUM.] Mr. Dickerson rightly remarks that it is disadvantageous to directly control the distribution of the water upon the carbide by means of the holder of the gasometer. In fact, the water cock may remain open before the holder has moved, and there may thus fall upon the carbide an excess of water, giving rise to a production of acetylene greater than the capacity of the holder warrants. The object of the Dickerson apparatus is to prevent such overproduction and to furnish water or carbide to the gas generator only as long as the gasometer will have been emptied of the desired quantity of gas. Fig. 10 shows a modification of the gas generator relative to the introduction of the carbide into the water; but the same letters designate the same parts. We shall describe the operations corresponding to the figures. [Illustration: FIG. 10.--MODIFICATION OF THE GAS GENERATOR OF THE DICKERSON APPARATUS.]