Interesting thread.

The song has a Roud number (24541), though only one entry in the online index. It's a small fragment in the Bayard collection, which you can hear on youtube: Charles S. Brink at 14:49.

The fragment has:

  My Uncle Dick, he took a stick,
  And he killed five hundred Irishmen,
  At the Battle of the Boiling Waters.


A Great War Forum, in a thread on My Old Man's A Dustman parodies, has this post from MikeyH (Lieut-Colonel):

   "A playground ditty we would sing in the 1950's in Lancashire ran something like this:-
  
   
  
  Oh my Uncle Ben he killed ten men
  
  At the batle of Boiling Water
  
  One lay here and one lay there
  
  And one lay round the corner
  
  One poor soul with a bullet up his hole
  
  Lay crying out for water
  
  A man came by and pissed in his eye
  
  At the battle of Boiling Water.
  
   
  
  Interesting to see similar lyrics in the 'Battle of Mons' quoted above." 
  

Mick