sentences:  A patent for adjustable belt pulleys for motorcycles dating back to 1912, shows Cecil Stanley Burney, Edward Alexander (Alec) Burney, and pioneer aviator Harold Blackburn trading as Burney and Blackburne (not Blackburn), operating from Northchurch, Berkhamsted.They were incorporated shortly afterwards as Burney and Blackburn Ltd, at which point Harold Blackburn sold his stake to the competition riders Cecil and Arthur Roberts.As a "dividend" for his investment, Blackburn was given a motorcycle and sidecar from the original production batch.