Unfortunately it doesn't say what sort of servant he was

The will is dated 1819.
It says To my faithful and devoted servant Graham Campbell now in service in Kilmory in Argyle an annuity of 42 pounds. This seems an awful lot of money for those days.
Graham is the 3rd servant mentioned after Peter Esq's father's "man of colour" and his wife (50 pounds total annuity) and Mrs Flower the housekeeper (maybe of the London residence), 52 pounds 10 shillings. The other servants are not mentioned by name but each get a 10 guinea "bonus".
All theories gratefully received !
