reading through the posts, what strikes me is how universal the song is.   
   Anyone can recognize a place where barges pass, and relate to it as their own   
   location. I also find it intriguing that the legend about a sick girl/woman is   
   also fairly universal,    
   especially with the respect to humming the last verse as a way of honoring   
   this person's memory.   
      
   And to the running light issue, from the very brief research I found, running   
   lights of red and green are documented as far back as 1848 when the Lord High   
   Admiral (British) published regulations requiring this combination of lights.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)