We give herewith, from Le Genie Civil, illustrations and brief descriptions of some of the more prominent apparatus used for the manufacture of acetylene gas.

Trouvé Apparatus (Fig. 1). - The principle of the gas generator is that of the hydrogen briquet already applied by Mr. Trouvé in his portable lamp. It consists of two vessels, one entering the other. The internal vessel is provided at the bottom with a discharge pipe communicating, through a cock, with the gasometer. It carries a suspended open work basket containing the carbide of calcium. The bottom of this vessel is provided with an aperture through which it communicates with the external vessel containing the water. The latter is brought to a level in the two vessels and attacks the carbide. The acetylene formed is disengaged and enters the gasometer. At the same time, the excess of pressure forces back the water into the external vessel in suppressing its contact with the carbide. The latter, nevertheless, continues to be attacked slowly through the action of the aqueous vapor. If the cock of the apparatus now be closed, the gas will accumulate in the interior vessel and will soon escape through the aperture in the bottom in raising the column of water. Mr. Trouvé has endeavored to remedy this inconvenience by arranging the pieces of carbide in the basket in distinct layers separated by disks of glass.

He has, besides, provided his apparatus with an electric alarm, designed to give warning when the holder is too full or when it is on the point of being empty.

Fig. 1. - TROUVE'S ACETYLENE APPARATUS

Clauzolles Apparatus (Fig. 2). - This apparatus consists of a gas generator, A, hermetically closed and containing the carbide, of a water reservoir, B, communicating with A through a cock, H, and of a gasometer, D, connected with A by the tube and cock, A. The cock, H, is provided with a lever fixed by its extremity to a chain that follows the motions of the holder. When the latter rises or descends, it causes the cock, H, to close or open.

Fig. 2. - CLAUZOLLES' ACETYLENE APPARATUS

The receptacle, A, is held by a cover fixed by means of four nuts which are removed when it becomes necessary to renew the carbide. The receptacle is removed and replaced by a duplicate one, after the cock, K, has been closed so as to keep the gas in the gasometer.

Bon Apparatus (Figs. 3 and 4). - The acetylene is produced by the reaction of the water falling in small quantity upon the carbide contained in the gas generator, A. The latter is divided into compartments, F, which, filled with carbide, are reached by the water only successively and progressively. When the carbide of the first compartment is exhausted, the water enters the second, and so on. The dimensions and numbers of these departments vary with the size of the apparatus. Each of them contains from ½ lb. to 4.5 lb. of carbide. The box with compartments, F, is covered by a rectangular holder, H, which enters a flat-bottomed receptacle, E, opened above and filled about two-thirds full of water. The latter serves as a hydraulic joint, and, at the same time, as a refrigerator. The holder, H, carries a lead pipe, G', terminating in a funnel into which falls the water from the reservoir, C, led by the pipe, G. This water flows through the extremity, i, of the pipe, G', into the first compartment.

Each of the compartments carries, upon the top of the partition that separates it from the following, an aperture through which the water enters the adjoining compartment as soon as the gas in the preceding compartment has made its exit from the gasometer, and so on until the last in the order of the numbers of the compartments.

Figs. 3 and 4. - BON ACETYLENE APPARATUS

The flow of the water through the pipe, G, is regulated automatically by a cock, r', with counterpoise. The holder, in rising, closes this cock and gradually cuts off the entrance of the water. The gas produced, once consumed, the holder descends in opening the cock, and the water begins to flow again.

The disengaged acetylene enters the gasometer, B, through the pipe, D. The extremity of the latter is bent into the form of a swan's neck. The gas is thus forced to bubble up through about 2 in. of water, in which it is cooled and freed from all traces of the ammonia that it may contain. The cock, R, in the pipe, D, is a three-way one. The first opens and the second intercepts communication between the gas generator and the gasometer, while the third puts these two parts of the apparatus in communication with the atmosphere.

The total capacity of the gasometer is so calculated that the acetylene produced by a single one of the compartments, F, may be stored up therein upon its exit from the gasometer through the pipe, K. The acetylene traverses a purifying column, I, filled with pumice stone saturated with a solution of sulphate of copper and surmounted by a thin layer of carbide of calcium. The object of the sulphate of copper is to free the gas from phosphorus and arseniuret of hydrogen. The layer of carbide serves to dry it.

It is well to use salt water for the gasometer, as acetylene is but slightly soluble therein.

Lequeux-Wiesnegg Apparatus (Figs. 5, 6, and 7). - The apparatus represented in Fig. 5 is capable of being used in lecture courses. It consists of a tank, B, and a holder, A, which is provided at the top with a wide aperture closed by a hydraulic plug, F. When the apparatus is at the bottom of its travel and ready to be filled with acetylene, the plug, F, as well as the basket, D, and the bucket, E, are removed. The quantity of carbide necessary to fill the gasometer is introduced into the basket. After care has been taken to put a certain quantity of water into the gutter forming the hydraulic joint of the plug, F, the parts, E, D, F, are introduced into the tube, C, in operating rapidly enough to prevent the loss of gas. The holder immediately rises as a consequence of the production of acetylene. The gas redescends through a tube to the bottom of the tank and rises laterally in a column by serving as a guide to the holder and as a support to the cocks designed to send the gas to the points of utilization.