A Bathroom Break

When my Uncle was nine years old he visited a friend's house.  While there he excused himself to go to the bathroom.  He noticed a type of tank he had never encountered before: the tank was above the toilet and had a chain hanging down.  My uncle pulled the chain, gently at first.  Nothing happened.  A second pull, slightly stronger.  Nothing happened.  Finally, a third great yank...and...WHOOSH!  My uncle ran out the bathroom yelling, "I didn't do it!"  

After he told this story, and with my daughters still giggling at the dinner table, I asked my uncle if he went to the bathroom afterwards.  He replied, "What do you mean?  I went in my pants."