Not all clocks are in a separate room, some are in the ringing room, which can make it awkward to ring some bells. The bell ropes pass through this room, on their way to the belfry above.
The clock is mains powered but at one time the Verger came up once per day to wind up the three sets of weights. A very heavy swinging pendulum controls the time. It is not as accurate as a quartz clock, but that was all that was available to the Victorians when this clock was made. In the picture to the right, the pendulum hangs in the centre suspended by a thin strip of metal.
This photo shows the drum that strikes the quarter hours on the bells. These are the same bells we use for ringing. Occasionally a different set of bells may be used. As the drum rotates, the studs lift each of the five fingers up. The lifted finger pulls on a wire and via various levers into the belfry above. This raises the clock hammer away from its rest. As the stud passes, the finger is released, dropping the hammer on the side of the bell.
The picture below shows a crank above the clock case and the clock hammer beside the bell. The clock hammer at rest, is supported just clear of the bell. As the hammer drops, the front stop flexes to allow the hammer to hit the bell momentarily. If the hammer were to rest on the bell it would dampen the sound.