I have data on Sally Marquand but cannot confirm her origins except that she married Joseph Hill Beavan in 1796 and is mentioned in the will of her father John Marquand (proved in 1810).
It seems John was a surveyor for the Navy and the Crown and google provides many references. Allegedly, his father was Charles Marquand, civil engineer who designed bridges and worked on Westminster bridge. Allegedly he was born in Guernsey where Marquand is a common name. Can anyone confirm any of this with confidence?
I'd really appreciate any help.
Chris