I think the antiquarian Steve is trying to remember might have been Joseph Train FSA Scot.(1779-1852) an Ayrshire man who was an excise officer in Galloway, and who corresponded over a long period with Sir Walter Scott, providing him in particular with the character of 'Old Mortality' in the novel of that name.

There is a Memoir of Joseph Train, written by John Patterson in 1857, which is available to read in the Internet Archive, and which contains much information about Train's researches in Galloway and elsewhere.

There is a good article by Angus Fraser about Train in the Oxford Dictionary of National Biography, which you should be able to access online through most UK libraries.

I came across Train when looking for the source for "Ayrshire Lasses", which Train attributed to John Riddel "the best musician Scotland ever saw".

Train's early verse collection of songs and traditions from Carrick and Galloway was published in 1814 as Strains of the Mountain Muse.

Matthew