[generalbrando]

I might get evil looks for releasing "secrets," but it's not like someone couldn't have seen in the pit any told you anyway.

They had a string that they pulled. If you attach the string to inside of the front of the smallest, then run the string through the tube to the back the up the next tube and have it go through a loop in the front and then back and up the next... Basically you make it so the string is nice and long in there and then you shorten it and the thing that and shorten is the distance between the loop and the back of the tube. I'm almost sure this is how they did it (memory is foggy). Either way, this method would work.