Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.2 9/18/84; site ames.UUCP
Path: utzoo!watmath!clyde!bonnie!akgua!sdcsvax!sdcrdcf!hplabs!hao!ames!jaw
From: jaw@ames.UUCP (James A. Woods)
Newsgroups: net.followup
Subject: Re: Permutation Algorithms and Change Ringing
Message-ID: <736@ames.UUCP>
Date: Fri, 28-Dec-84 23:21:35 EST
Article-I.D.: ames.736
Posted: Fri Dec 28 23:21:35 1984
Date-Received: Sun, 30-Dec-84 01:59:54 EST
References: <195@cheviot.UUCP>
Organization: NASA-Ames Research Center, Mtn. View, CA
Lines: 48

# Note:  The following tintinnalogical offering should be read whilst humming
# Pete Seeger's "The Bells of Rhymney" (1964) in the key of control-G.

     We laud our very own campanologist Robert Stroud (ukc!cheviot!robert)
for his commentary on change-ringing.  His account certainly rings true;
I only wish to add a reference to the lore, to be found in the
December 1977 issue of ACM Computing Surveys.

     In his fascinating addendum to Robert Sedgewick's classic
exposition "Permutation generation methods" (appearing in the same journal,
June 1977), a Mr. I. R. MacCallum of the Dept. of Computer Science,
Univ. of Essex at Colchester, chimes in to discuss the following bits
of ephemera:

     (a) the roots of the Johnson/Trotter algorithm (1962) in the early
         years of the 17th century, as reported in the collaborative effort
         of Stedman/Duckworth in 1688 ("Tintinnalogia", also avail. as
	 a Kingsmead Reprint, Bath, 1970).

     (b) the complex definition of "peals" and "extents" provided by the
	 Central Council of Church Bell Ringers, with applicability
         to the playing of Grandsire Triples, a particularly harmonious
	 composition of 5,040 (7!) changes.  MacCallum, incidently, offers
	 Algol 60 code for a Grandsire peal composed by John Vicars of Oxford
     	 to the interested reader.

     (c) accounts of 8-bell extents (40,320 changes), the only "true"
         performance (i.e. verified by independent umpires) being achieved
	 by the Leicester Diocesan Guild at the Bell Foundry, Loughborough
	 on Saturday July 27th, 1963, in 17 hours 58 1/2 minutes.

     Ah, the stuff of Guinness Book!  I consider it right up there
with Sedgewick's three-instruction permutation generator inner loop.
Since campanologists may not resort to "visible aids to memory in
conducting or ringing", the fine (read "appealing") art practiced by
Mr. Stroud is algorithmic, indeed.

     -- James A. Woods	{hplabs,ihnp4,vortex}!ames!jaw  (jaw@riacs.ARPA)

P.S.
     This writer, also, is eagerly awaiting the Macintosh multi-voice
rendering of Plain Bob Major for his "wallpaper music" collection.
Perhaps bessel(3M) functions would serve as the appropriate inharmonic
sound envelope, with menu bars for Tibetan, Big Ben, and Liberty bell
variants.  Next stop -- a Phillip Glass machine!

P.P.S.
     I hope net.audio and net.music.folk are listening in on this...