There are several types of traditional music collections that don’t fit precisely into the category of “Scottish dance and performance music of the 18th and 19th centuries”. The dance manuals, so popular in London and Bath in the 18th century vary hugely in their content of strictly Scots material: Joshua Campbell (C14), 27 volumes, 1790-1817, was definitely “in”; for example, John Walsh, a prolific London dance music publisher of the 18th c. was more in the English camp and has dropped out.
The song books (both Gaelic and Scots, with words) in general form a separate group; James Johnson’s “Scots Musical Museum” (1771), however, contains so many of the original song airs of the traditional repertoire, it would be inappropriate to exclude it; it appears as J3 in the Index. A huge proportion of the song airs of the period appear elsewhere in the listings.