 The miniature gasometer on the eastern side of the building is connected onto the inlet mains for the main Gasometers on site (from the point it leaves the purifiers in the Horizontal Retort Building), with the second being directly connected to the outlet mains between the Gasometers and the main governor.The main governor is located at the back of the building along with an exhauster and various meters and pressure gauges.The original governor was first installed in 1860 when the gasworks were first built and changed little since then though the building itself has been rebuilt.