Away too among the rocky shores of the western isles of Scotland his (James Riach) voice was often heard above the waves of the mighty Atlantic during the time of the Lewis fishing. In the moral wastes of the Island of Barra, where ignorance and superstition reign triumphant, his voice was often heard like another John the Baptist in the wilderness of Judea, crying - "Repent, for the kingdom of heaven is at hand" - and frequently, in all these places, mighty power accompanied the word spoken, so that many believed on the Lord to the saving of their souls.
One reason of his success was his unshaken faith in God, and his entire dependence on the mighty life-giving Spirit to carry home with power the truths which proceeded out of his mouth.
"James Turner, or how to reach the masses." by E McHardie, page 205-6.
James Riach was an outstanding revivalist and beautiful follower of Jesus. There is little known of him except that he worked at a time of revival and he ministered in the power of God, so I am sure there were many salvations here.
I do not know the date - it has to be somewhere between 1860 and 1871, probably several times.