A year after his first ‘Gradient’ derailleur (see UK Patent 1896 1,570), Edmund Hodgkinson produced this, much more sophisticated and coherent design. This three speed system now looks extremely similar to a 1930s TriVelox. One difference is that Edmund Hodgkinson placed the large cogs towards the outside and the small cogs towards the centre of the wheel hub.

• Publisher: UK Intellectual Property Office
• Inventor: Edmund Hugh Hodgkinson
• Country: UK
• Date: UK application filed July 1897
• Derailleur brands: Gradient
• Derailleurs: Gradient