Mr. Masssly, 

 Dear Sir, 

 Thank you for undoing my edit - I find that Falmouth Moor was only a marsh with a stream, as distinct from the narrow inlet to the sea of Helston during the whole of the 12th century and a little beforehand; so it did not fit in with the verified truth of the pre-1260 limited harbour of Helston, before the Loe Bar blocked off the incoming sea.  Decayed seaweed has been seen on a cliff side slate rock below Helston. 

 Regards, 

   Andrew