"The Mountain Dew" was a song about poitín (Irish moonshine) with lyrics by New York musical theater great Edward Harrigan and music credited to Harrigan's orchestra leader David Braham.
The tune, however, owes an obvious debt to the older song "The Girl I Left Behind.
[1] and was later printed in Colm Ó Lochlainn's 1916 Irish Street Ballads.
The earliest recording in the 78 rpm era was made in New York in 1927 by John Griffin for the Columbia label.
Lilting is often added to the song, either after every second verse or once at the beginning and once at the end, to the same tune as the lyrics.