[r-t] Definitions so far

[Richard Smith]

A comment Iain made to me off-list over the weekend has 
persuaded me that I should change some of my definitions re 
changes.  In particular, he has persuaded me that the 
distinction between a /plain change/ and a /single change/ 
is unnecessary, as a corollary my definition of /ordinary 
change/ was too high-level.  I have introduced the term 
/oridinary working change/ for what was previously an 
/ordinary change/.  I've also concluded by defining change 
ringing.  Comments?

RAS


Version 0.2:

C.  Definitions concerning changes

1.  A /change/ is the transposition that effects the
progression from one row to the next.  They are defined in
terms of the places of the bells affected rather than the
bells striking in those places.  Thus a change that just swaps
the bells in seconds and thirds place is the same as any other
change that just swaps the bells in those places, regardless
of the particular bells striking in seconds and thirds place.

2.  Changes between ordinary rows may be classified as
follows:

   (a)  The /null change/ is the change in which no bells change
   place.  The row preceding the change is the same as the row
   following it.

   (b)  A /plain change/ is any change effected by the
   interchange of precisely one pair of bells striking
   consecutive blows in an ordinary row.

   (c)  An /ordinary change/ is any change that combines the
   effect of one or more plain changes, each of which affects
   different bells.  The null change is excluded from this
   definition by convention.

   (d)  A /jump change/ is any progression between ordinary
   rows that is not an ordinary change, nor the null change.
   Jump changes necessarily involve bells moving more than one
   place between consecutive rows: such motion is called
   /jumping/.  Although documented in both the early and recent
   history of change ringing, jump changes are not commonly
   used.

3.  Ordinary changes may be further classified as follows:

   (a) A /single change/, /double change/, /triple change/,
   /quadruple change/, etc. is an ordinary change in which
   exactly one, two, three or four pairs of bells are swapped.
   A single change is synonmous with a plain change.

   (b) The /cross change/ is the ordinary change in which every
   bell swaps places with an adjacent bell.

4.  A bell whose position in the working row is not affected
by the change is said to make a /place/.  A bell that makes a
place in seconds place is said to /make seconds/, and
similarly for other positions.  A covering bell is not
considered to be making a place as it is not part of the
working row.

5.  A /stage change/ is a change that progresses from a row of
one stage to a row of a different stage.

6.  A /cover change/ is change other than a stage change which
either alters the choice of covering bell or bells, or alters
the order in which they strike.

7.  A /working change/ is a change that is neither a stage
change nor a cover change.  Equivalently, it is a change
affecting only a the working row.  An /ordinary working
change/ is a working change that is also an ordinary change.

8.  Ordinary working changes (and the null change) are
conventionally denoted by writing in order the places made.
For example, in Minimus the single change that swaps the bells
in seconds and thirds place is denoted '14', as places are
made in first and fourths place.  Bell symbols are used for
places above ninths place.  The cross change is variously
denoted 'X', 'x' or '-'.  This representation of a change is
called its /place notation/.

9.  /Change ringing/ is the practice of ringing rows without
interval, where the progression between rows is defined by
changes.  Commonly the first and last rows rung in a piece of
change ringing are rounds.