Essay... I thought about that possibility as well,
and explored most of the links for Peterboro, NY...
going back to 1795... and it (appears) the 'ugh'
was not the name of the town... the link below
being one of many I read through...
http://en.wikipedia.org/wiki/Peterboro,_New_YorkLogic would suggest the postmark being British,
(albeit over a U.S. stamp) with the N.V. possibly
being Nene Valley... the "Y or V" most certainly
is no distortion of the CDS of an "H", given the
"H" in PETERBOROUGH is as well defined as it is...
Lastly, the usage of an 1865 stamp in 1881 could
very well be attributed to the sender not being
aware of any required usage of British requirements,
and, might have been the only stamps the sender had,
either visiting the UK or after (possibly) even
residing there for up to 16 years...
Finally, given we have a stamp "on piece" who's to
say the cover didn't have British postage on it as
well...