On the back of a silhouette...

[Archie's Mum]

It's that word at the end of the first line that is the key, I am sure.

And why is Culwath written at an angle like that????

I think it is written at an angle possibly because whoever wrote it wasn’t sure of spelling or other, wrote Bishop, left a space and wrote Grounds (which is what I think it is) then came back and added Culwath. Then added the note at the bottom.

 

[Daft Bat]

There is a Culworth Grounds Farm - it appears Culworth Grounds is an area south of the village, so like AM suggested is the word Grounds?
So Mr Bishop of Colworth Grounds perhaps?

I think that this is the best idea yet. Thank you @MollyMay and @Archie's Mum

I wonder who Mr Bishop was - the silhouette is from about 1780/90 and he looks to be in his 40s/50s/60s so a birth around 1720/40

 

[Daft Bat]

I summarised the findings for Tim and received the following from him:

Thank you and your team...fascinating stuff.....love how it twists and turns to unravel different avenues.
Much appreciated.
Tim.xx

 

[Archie's Mum]

I think we need a very large magnet for that needle in the haystack!

 

[MollyMay]

I found this yesterday, but was not too sure whether to mention it or not.
In the Clandestine Marriages registers, is one for an Elizabeth Bishop to John Upton 17/9/1717 at Cripplegate. John was a gardener.
It may be pure coincidence, but the only link between the 2 names (almost) that you have, and the correct time for them to have a son in the right time frame.

I did peruse the St Mary Culworth PR's (on Anc) and there are no Upson, or similar in the register until around 1800, but Upston seems more prevalent in the neighbouring Buckinghamshire area.

 

[Daft Bat]

Thanks, @MollyMay that does certainly look like a connection!