With regard to the origins of "She's Like The Swallow", Neil Rosenberg's notes to volume one of Vinland's collection "Songs of Newfoundland and Labrador", mentioned by himself in this thread on April 19, state that the song "was was first collected in 1930 from John Hunt of Placentia by English folksong scholar Maud Karpeles, who published it in 1934 along with a piano setting by her brother-in-law, the famous composer Ralph Vaughn Williams."
Edith Fowke's notes to "The Penguin Book Of Canadian Folk Songs" identify the song as "a distinctive Newfoundland variant of a large family of songs about unhappy love of which 'A Brisk Young Sailor', 'Must I Go Bound', and 'Died For Love' . . . are the best known." She refers to affinities with a 17C song and an unpublished song collected by Cecil Sharp.
Jim Lad, I am sending you a PM.