"The blackbird of Avondale, or the Arrest of Parnell" is on the Bodley Ballads website. It seems to be an imitation of "The Ladies Lamentation", 1651, which is in the Scarce Songs 1 file on my website. The Irish (much later) called this "The blackbird" and there are many copies of the 'Irish' tune for it from the late 18th century on (an ABC of is in file S1 on my website). The tune is first found as "The Bonny Lass of Aberdeen" in Oswald's 'Caledonian Pocket Companion'.