Thanks for your responses. "Puffing billies", eh? Hmmm.

Isn't there a word for words or phrases we mis-hear, and then mis-quote, as jmh's father's "milk is an egg" and Malachy McCourt's "A Monk Swimming" for "amongst women" in the Hail Mary? (I must confess that I too said "a monk swimming" when I prayed the Hail Mary as a child. I figured that a monk is holy and therefore belonged in a prayer. And, jmh, you're right: we certainly didn't question religion back then!)