Summary: This week, Ruairidh continues his quest to find even more place-names with the word torc, the Gaelic for boar, in them. He has plenty of fascinating areas to discuss. He then ponders why there are so many names that are boar-based in Scotland? Find out more in this week’s letter. Accompanying text is available in both English and Gaelic at bbc.co.uk/litirbheag