Tre, Pol, Pen
By their Tre, their Pol, and Pen, Ye shall know the Cornish men.'
The extreme east of Cornwall is noted for Tre, the extreme west for Pol, the centre for Pen. On December 19th, 1891, the following residents are mentioned by the Launceston Weekly News as attending the funeral of a gentleman who lived at Tre-hummer House, Tresmere: Residents from Trevell, Tresmarrow, Treglith, Trebarrow, Treludick, etc., with Treleaven the Mayor of Launceston.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894