15a What happened repeatedly in 1770 (5), 26a Journal that is enlightening for insiders (6), and 6d Riding (not South) behind two others (5). The answers look like Event, Lancet and Third, but I need help parsing, please.
The word `Riding` comes from the ancient word `Thriding` meaning a third. Most of South Yorkshire used to be in the West Riding - until the Government decided to annoy us all by imposing administrative changes. York was not in any of the Ridings but its City walls marked their boundaries.