Are all GZ34's born equal?

[CambridgeWorks]

Hoping not too OT, but I remember over 50 years ago an article about the plughole water, I think on "About Anglia" regional 6pm tv programme. I mentioned to my physics teacher the next day that depending on which way the water had started rotating, my experiment showed that it continued in the same direction. He agreed.
I still didn't come top of class!
Rob