Acknowledgements
This article has benefited greatly from discussions with Chas Critcher and from editing by John Spink, as well as from helpful encouragement from Jonathon Long, Neil Ravenscroft and Beccy Watson. The last paragraph was inspired by Michael Gard’s sabbatical during 2006 at Leeds Metropolitan University but he has not yet had sight of this paper. Needless to say, all errors and confusions are attributable solely to the author.