I have a very strong suspicion that the entries for Thomas (1808-1884) and Sarah (1818-1909) in your database are for my wife's great-great-grandparents (ages and addresses in the censuses of 1861-1901). I realise that the gravestone no longer exists but wonder whether there is any additional information in the cemetery records (e.g. burial in the same grave) that might confirm my suspicion.