[r-t] Fwd: "double" cambridge?

[edward martin]

2010/1/23 Graham John <graham at changeringing.co.uk>:
> Eddie sent some questions re method symmetry from Ann
>
>> ... not symmetrical in the classical way around the treble
>
> Eddie - You obviously haven't been keeping Ann abreast with historical
> postings from this list, or the musings of PJE. Try the page below for
> starters.
>
> http://www.cantabgold.net/users/pje24/sym.html
>
> Graham
>

Thanks for your speedy reply; however I think the key point to what
she was saying was more a matter of semantics :
"Don't we need two words for these two kinds of doubleness?"

In 18th century ringing books, if a method was referred to as ‘Double’
it meant that places were made both sides of the treble. This is no
longer the case. It is my understanding that the requirement to call a
method ‘Single’ only applies to methods that are purely plain hunting
(i.e. have no internal places) below the hunt bell. With this
definition of a single method there's always a 1-1 relationship
between a double method and a single method (you can take any
seven-lead plain major method and perhaps construct a single method by
removing all the internal places from under the hunt bell, and
conversely any method which has no internal places below the hunt
bells can be doubled up). So there is no ambiguity about the members
of the single/double pair. It therefore follows  that in a ‘Double’
method, (where the PN of the second half lead is a mirror reflection
of that of the first half lead) because the place notation above the
treble is mirrored with place notation below the treble, the work off
the back is the mirror image of work off the front; Now, this is not
case with Double Cambridge Cyclic Bob Major/Minor /Royal so, why is it
called ‘Double’ ?

To try to understand this, using Don Morrison’s fantastic ‘Method
Information’, I typed in the notation of what ought to be Single
Cambridge Cyclic Bob Minor/Major/Royal and got ‘unnamed’. The LHs were
cyclic & I suppose that the methods just have not been rung &
therefore not officially named, but when/if they are then they will
have to be named ‘Single Cambridge Cyclic’.

This still does not answer the missus’s question which seems to me
that there are conflicting uses of the word ‘Double’ when used in the
name of a method. Am I right in thinking that a lead block whose PN is
mirror reflected about the half lead, from rounds cannot produce a
cyclic LH, If so then, since we can have both Single & Double Cyclic
methods, isn’t this a specific use of the word ‘Double’ and wouldn’t
Double Cambridge Cyclic be better named Cambridge Double Cyclic ?

mew