Hmmm.
I see several lines contain 'Longat'. This could be Longate, which is a street in the town centre. It's followed by a hieroglyphic that I read as 'Phd', in other words an abbreviation for Peterhead.
Others look like Kirktown (which would be close to the kirk), Damhead, Meikle Cocklaw and several that I can't make sense of.
So I think you are right that it is a street or location rather than a signature.