This is an old revision of this page, as edited by Andy Dingley(talk | contribs) at 22:22, 3 November 2012(redir - neither necessarily optical nor rotary, but it should cover the broad point). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.Revision as of 22:22, 3 November 2012 by Andy Dingley(talk | contribs)(redir - neither necessarily optical nor rotary, but it should cover the broad point)
