Campanology - Change Ringing

Change Ringing

In England the bells in church towers are generally hung for full circle ringing: every bell swings through a complete circle (actually a little more than 360 degrees) each time it sounds. Between strokes, it sits poised 'upside-down', with the mouth pointed upwards; pulling on a rope connected to the bell swings it down and its own momentum swings it back up again on the other side.

These rings of bells have relatively few bells, compared with a carillon; six or eight-bell towers are common, with the largest rings in numbering up to sixteen bells. The bells are usually tuned to fall in a diatonic scale without chromatic notes; they are traditionally numbered from the top downwards so that the highest bell (called the treble) is numbered 1 and the lowest bell (the tenor) has the highest number; it is usually the tonic note of the bells' scale.

To swing the heavy bells requires a ringer for each bell. Furthermore, the great inertias involved mean that the ringers have only a limited ability to retard or accelerate their bells' cycle. Along with the relatively limited palette of notes available, the upshot is that such rings of bells do not easily lend themselves to ringing melodies.

Instead, a system of change ringing evolved, probably early in the seventeenth century, which centres on mathematical permutations. The ringers begin with rounds, which is simply ringing down the scale in order. (On six bells this would be 123456.) The ringing then proceeds in a series of rows or changes, each of which is some permutation of rounds (for example 214365) where no bell changes by more than one position from the preceding row(this is also known as the Steinhaus-Johnson-Trotter algorithm).

In call change ringing, one of the ringers (known as the conductor) calls out to tell the other ringers how to vary their order from row to row. Some ringers practice call changes exclusively; but for others, the essence of change ringing is method ringing.