Description of the Process of Manufacturing Coal Gas, for the Lighting of Streets Houses, and Public Buildings / With Elevations, Sections, and Plans of the Most Improved Sorts of Apparatus Now Employed at the Gas Works in London and the Principal Provincial Towns of Great Britain; Accompanied With Comparative Estimates, Exhibiting the Most Economical Mode of Procuring This Species of Light

by Friedrich Christian Accum

The governor must be firmly fixed to the nearest beam or wall, as the least vibration will render the lights connected with it unsteady.

When a situation cannot be obtained sufficiently warm to prevent the water from freezing, the machine must then be wrapped round with woollen cloth, or any other bad conductor of heat. The cellar where the gas enters the house, has generally been found the most convenient situation.

For supplying any deficiency of water which the governor may require; a small funnel with a curved tube is placed for this purpose at the top of the governor. When the governor is filled to its proper height, the water will begin to run out of the siphon.

The mode of regulating the height of the flames will be stated presently.

Fig. 11, [plate III.], exhibits a portable governor or regulating guage, combined with a gas metre in one case. A, is the inlet pipe which conveys the gas into the machine, and B, is the pipe leading from the governor to the lamps or burners. D, a label expressing the quantity of gas discharged by one revolution of the wheel, and the number of lights which the metre is capable of supplying when the pressure of the gas in the inlet pipe is of a density sufficient to support a column of water of half an inch in height.

In those situations where the pressure of the gas is equal in density to support only a column of water one-quarter of an inch in height, a metre of a larger capacity must be adopted for supplying the same number of lights; and if the pressure of the gas be equal only to support a column of water one-eighth of an inch in height, the capacity of the metre must be still larger, and thus the capacity may be increased so as to equal every pressure that may occur. The index which registers the number of revolutions, and consequently the quantity of gas which passes through the metre, is shut up in the projecting case, near H, furnished with a lock and key.

Previously to the gas metre being filled with water, ascertain that the regulating cone is screwed perfectly air tight into the top of the floating vessel which receives the gas, and that the regulating aperture in which the cone moves, together with its spindle and guide rods, work perfectly free and without friction. Raise the floating vessel to its highest elevation, thereby closing the regulating aperture suddenly with the cone; in this situation it must not rub when turned and tried on every side, but descend with the least friction.

The gas metre and regulator being thus examined and fixed, the machine may be supplied with the requisite quantity of water in the following manner:

Open the stop-cock which admits the gas into the machine; open also the aperture E, which serves to show the pressure of the gas in the machine, and likewise the opening G, which lets out the air whilst water is poured in at the aperture H. The superfluous quantity of water will run out by the siphon tube at K.

Pour water also into the governor until it runs out at the aperture at M; and when this has been accomplished, till the gas metre with water at the opening H, until it overflows at the aperture K, when the surface of the water will appear at the cypher line on the scale board. The apertures F, G, H, K, and M, may then be closed, and the machine is ready for action.