This version of the Ram Jam Inn story usually goes something like this ...

An 18th Century guest at the inn couldn't pay his bill, so in recompense he offered to show the landlady how she could get two different ales from the one cask. He drilled a hole in a full barrel in the cellar and got her to ram her thumb into the hole to stem the flow. He drilled another in the other side of the barrel and again got her to plug the hole with her other thumb. While she was thus 'jammed' keeping the ale in the barrel, the guest fled, leaving the landlady with an unsettled bill and sore thumbs.

The version I had, which is somewhat different, is about two tricksters who performed a rather more elaborate con on the landlord of the pub.

:-)
Ian