The fixed golden ball in the centre of the dial represents the earth.
A small bell located behind the clock dial chimes the quarters. On the hour, this is followed by the deep sound of the striking of the huge Peter Bell which hangs high up in the tower above.
The text PEREUNT ET IMPUTANTUR below the main dial translates as ‘The hours pass and are reckoned to our account’.
In the 18th century the small upper dial was added with a single hand to indicate the minutes.