I've come to the conclusion that I am barking up the wrong tree.
I am trying, in my round about way, to find the father / family of my Mary Arbuthnot who married Donald aka Daniel McPhail in 1784 in Edinburgh. The marriage says her father is "Robert Arbuthnot indweller in the Parish of Wymess." I don't think he is the Robert I asked about.
Thanks to all who tried to help me.
Anne