[r-t] Plain Bob lead heads/ends (was ringing-theory Digest, Vol 89, Issue 9)

[Matthew Frye]

On 10 Feb 2012, at 08:15, edward martin wrote:

> On 10 February 2012 00:20, Matthew Frye <matthew at frye.org.uk> wrote:
>> 
>> I very much did read what you said, did you?
>> I interpret what you wrote as saying that ALL palindromic methods give pb lead ends, BECAUSE they have the correct bells swapping at the half lead. This should be IF they have the correct bells swapping at the half lead THEN they will give pb lead ends.
> 
> I agree that had I better phrased it my intention was to convey that
> at the half-lead, if one notes  the pivot bell and the pairs of bells
> that switch places AND if  the method is palindromic about the path of
> the treble, then a particular set of lead Heads & lead ends is
> inevitable For this set to be as in Plain Bob, the working bells must
> be in their plain hunt coursing order

I still think I prefer my phrasing to yours, but we do seem to be agreeing!
Slightly reluctant to quibble any more terminology, but I'm not particularly happy about the use of the phrase "coursing order" in this context as it implies (to me) a greater relationship than just the pairs of bells swapping (ie, where the pair are relative to eachother). eg compare Beverley & Cambridge, I would say each has a different apparent coursing order at the half lead, but still same pivot and pairs swapping.

> Believe it or believe it not, a similar situation DOES exist with twin
> hunt methods where the pivot points are when the 1,2 cross in 1-2 and
> in 6-7 (in triples) 8-9 (in Caters) etc
> 
> I hope that this is not too confusing but it is a demonstrable fact
> that some asymmetric even-bell methods can still have Plain Bob lead
> ends & lead heads;
> Likewise some asymmetric twin-hunt methods can still have Grandsire type leads

I am well aware of basic method construction...

> Therefore, to be considered 'regular' it does not seem to be enough to
> say that an even bell method must have plain bob leads nor that a twin
> hunt method must have Grandsire leads  because these can be achieved
> with either palindromic or asymmetric lead blocks.

Well, yes. I thought this was implicit in much of the earlier discussion.

MF