Brown was the longtime Keeper of the Advocates Library in Edinburgh (1766-1794), which, in the 18th century, was the de facto national library of Scotland.
Brown was also an able archer, who, on May 26, 1781, during a practice session "won eight successive ends, and nine successive shots in these eight ends, against the whole other of these shooters—an instance similar not known or remembered by any archer present to have happened before. This, it may be explained, occurred while shooting at rovers, and not in the butts, which, of course, makes the fact all the more wonderful. The gentleman who performed it was the Librarian to the Faculty of Advocates, and was at one time employed in collecting materials for a History of Archery and the Royal Company, but did not proceed very far with it" 1
- 1 Paul, James Balfour. (1875) The History of the Royal Company of Arches. pp. 97-98
Boswell took Dr Johnson to see the Advocates Library on August 16, 1773, and they had a discussion with Brown and James Ker, the Keeper of Records, which is recounted in Boswell's Journal of a Tour to the Hebrides.