Roy;

The authors of "COGSWELL & HARRISON" (Safari Press--2000) repeat that discussion with Harrison and Teasdale Buckell on page 44 of their book in reference to the Gllingham Street Works prior to its destruction by fire in 1922. In my reading of the histories of the London gunmakers this is the only reference to building a boxlock (in this case the Avant Tout) of any London maker.

Stephen Howell