Welcome to Cork
X:1 T:Welcome to Cork M:6/8 L:1/8 R:Jig S:O’Neill – 1001 Gems (1907), No. 30 Z:AK/Fiddler’s Companion K:G B/c/|dBG dBG|efg dBG|cec BdB|cAG FED| dBG ecA|gag fed|fed cAF|AGG G2:| |:G|Ggf gag|=fde f3|=Ffe fgf|edc dcA| Ggf gag|=fde f3|cde =fcA|AGG G2:|]
WELCOME TO CORK (Failte romad sa Corcac/Corcaige). AKA and see "Teddy Malo's Jig." Irish, Double Jig (6/8 time). G Major/G Mixolydian. Standard tuning (fiddle). AABB. It is possible Francis O'Neill renamed "Teddy Malo's Jig" from Ryan's Mammoth Collection (1883), as he occasionally did with other tunes he liked (and perhaps thought had an Irish provenance). Jack Gerrity, a fiddler residing in Brooklyn and prominent in the Irish dance halls, recorded the tune under O'Neill's title in 1920.
O'Neill researcher Paul de Grae could find no earlier Irish antecedents for the jig although he did note that Joyce's "Old Jerry Doyle", "from John Dolan of Glenosheen: 1845," seemed to him a rather distant relative. 
- Paul de Grae, “Notes on Sources of Tunes in the O’Neill Collections”, 2017 .