Figure 16: Regions in the “clappering plane” for which a bell can ring (a) right and (b) wrong, for the case in which the bell motion was initialised at angle so that the bell swings through a half circle from horizontal to horizontal. Colour shading indicates the bell angle in degrees at which the first contact occurs between clapper and bell, with a scale matching Figure 10. White symbols indicate the positions of the bells from Figure 9.