This is the UK version of French Patent 791,724. I have included it here because it shows that, by the mid 1930s, Lucien juy was already intending to export his derailleurs to Britain, and that his first concern seems to be to export touring designs, rather than his more racier models.

• Publisher: UK Intellectual Property Office
• Inventor: Lucien Juy
• Country: UK
• Date: French application June 1935, UK application June 1936
• Derailleur brands: Simplex
• Derailleurs: Simplex Route