Hi Richard, my Great-great-grandfather was William Johnston (b. 1793). I've traced this rather easily on this site, due mostly, I imagine, to your efforts in tracing your family tree. This makes us some kind of distant cousins. Oddly enough I was born Aug 2 just two years earlier than you, also in Cambridge, Ontario (Galt then). I wonder if you ever went to any of the Orkney picnics in Victoria Park in West Galt?
I am very grateful to find all this information. My uncle died recently and gave to my mother a copy of the tracing of his mother's family tree (Agnes (Addie) Sutherland of Sandside, Orkney). I've been meaning to look into my family history since the time I travelled to the Orkney Isles some 10 years ago. My uncles work gave me the push I needed and your work gives me a big jump start.
Feel free to email me if you're at all interested in the info I have on the Sutherland family.