Bell ringing

"Change Ringing" is the name for the way in which we ring church bells in Britain. Foreigners play tunes on their bells - which isn't terribly interesting if you can only afford three or four bells in your tower. We ring the changes by inventing complicated patterns. For example, imagine that you have four bells; you might ring them in this order:
1 2 3 4
In subsequent rounds you might ring
2 1 3 4
2 3 1 4
2 3 4 1
1 2 3 4
which takes you back to the beginning again. Much more complicated patterns are possible, so listen and enjoy.