Lighter.. a bit more about this is in an 1872 publication, and one of the tunes used foe the lyrics. Confusingly we have numerous titles to try and pick out as well. Some versions are not Loch Lomond, but Ben Lomond. So different titles, different spellings here and there, even of the word Bonnie, Loman' etc. This writer says that it was a street/fair song in its earlier form. So sometime between one part of the early Victorian period and the later, it acquires a different melody and identity that gets taken up. Supposedly one of the versions is in the Dunn Vocal Melodies of Scotland c 1842 (not the Gow one of the same book title). However, that is in archives and for sale, but not reproduced on-line.