There are several copies of Unfortunate Sally or Billy don't you cry for me (Recorded by Nic Jones on Unearthed as Billy don't you weep for me) in the Bodleian Ballad library. Most of them use the stange phrase 'she then committed susanside! in the water butt'

Here is one example

Can anyone shed light on this? (The exclamation mark is part of the printed text).