--following up a marginal annotation in the late G. Ross Roy's annotated copy of Egerer's Burns bibliography, reprints an 1815 letter by Burns's friend Dr John Mackenzie in the Irvine and County of Ayr Miscellany, which included the first publication of Burns's short poem inviting Mackenzie to a masonic dinner, and also of Burns's letter to Mackenzie, dated January 11, 1787.