Thanks - good to know the derivation.
For info, here are a couple of links to playbills that show the play.
From blplaybills.org:
Hatmarket:
http://storage.googleapis.com/blplaybills.org/large2/lsidyv4045b355_477.jpeg
Covent Garden:
http://storage.googleapis.com/blplaybills.org/large2/lsidyv3fa2b3ff_383.jpeg
Same ones on the BL viewer: