Good analysis may follow.
Now, just on the basis of this — ignoring all the other evidence, ignoring that the industrial revolution started in Scotland, ignoring that many of these breweries are nearer to sources of coal than sources of peat, ignoring that we know for a fact that several of the largest breweries made their own malt on site, ignoring that they used a lot of imported malt anyway … just on the basis of this map, exactly how likely do you think it would be that the beer from these breweries would have a peaty influence?
Of course this doesn’t happen if Ron Pattinson doesn’t compile the list of Scottish breweries in 1837 and build a map. Allowing Bam to take it a step further.
It starts with good, old-fashioned research. Often involving information you can’t just Google (or couldn’t until these guys did the work).