460
ufficient carbide to make a volume of gas nearly equal to the capacity of the gasholder. Thus each discharge of carbide very nearly fills the gasholder, but cannot over-fill it. The bell is provided with a vent-pipe i, which comes into operation should the bell rise so high that it is on the point of becoming unsealed. From the gasholder the gas passes through the pipe J, with cock e, to the purifier, which is charged with frankoline, puratylene, or other purifying material, whence it passes to the pipe N leading to the place of combustion. The generating tank is provided with a sludge-cock g, and a cleaning opening with lid f. This generating plant has been primarily designed for the use of acetylene for autogenous welding, and is made also mounted on a suitable trolley for transport for this purpose.
[Illustration: FIG. 37.--"SIRIUS" GENERATOR.]
(2) Automatic; carbide-to-water.
A later design of generating plant, known as the Type G, also primarily intended for the supply of acetylene for welding, has the carbide store mounted in the crown of the bell of the equalising gasholder, to the framing of the tank of which are attached a purifier, charged with frankoline, and a safety water-seal or valve. The whole plant is mounted on a four-legged stand, and is provided with handles for carrying as a whole without dismounting. It is made in two sizes, for charges of 5-1/2 and 11 lb. of carbide respectively.
GERMANY.
_Maker_: KELLER AND KNAPPICH, G.m.b.H., AUGSBURG.
_Type_: Non-automatic; carbide-to-water.
The "Knappich" generating plant made by this firm embodies a generating tank, one-half of which is closed, and the other half of which is open at the top, containing water. A small drum containing carbide is attached by a clamp to the end of a lever which projects above the open half of the tank. The lever is fastened to a horizontal spindle which is turned through 180° by means of a counter-weighted lever handl