In Latin: Sacred to the memory of Algernon, Earl of Mountrath, and the Countess Diana: she, surviving him, had wished to place this monument, 1771. As love united them happily in life, so love unites them, even after death, in the tomb. [Translation courtesy of Westminster Abby website.]
Literature: United in death.
Year of death: 1766.
Year of headstone: 1771.
Age at death: not given (classed as: Adult).