The Rev Peter Maclean came to Mull in 1843 and had 1,000 coming to his church. He also evangelised around the island and 'the Lord continued to countenance his labours; for years a manifest blessing accompanied him.' That is church speak for 'there was a revival.'
'The Progress of Evangelicalism', by Macleod, page 217.
There was also a move of God among the Baptists on the island.