No, I realize it's not very exciting. Perhaps not even interesting as it is, but bear with me. This lock-gate hinge taught me a very valuable lesson.
As mentioned at the time, most of the Locks (remember the significance of the capital L?) on the Leeds & Liverpool Canal have anti-vandal locks on their paddle mechanisms. A special key is needed to open them. Without this key, you simply can't get through the Lock.
At one of the locks (name/number forgotten now), my AV key, hanging out of my pocket from two cork floats, fell off the cord that tied it to them, and got lost in the grass. I found it again, used it - and dropped it! Right next to the lock. It bounced on the concrete, and tumbled over the edge of the chamber. And stopped, quite miraculously, balanced precariously on the narrow gate hinge, right above the water...
Why it stopped there is beyond me. The whole incident was watched by a group of walkers, and, as one, they gasped, then held their breaths as I bent down and carefully retrieved it. They applauded loudly, I bowed, thanked God, and opened the lock. If I'd lost that, our journey would have been halted for some time while I somehow got another one. It probably would have involved a very long walk to a chandlery.
The lesson learned? Have a spare key! Fixed firmly to floats!
(I've just bought one, and a spare BW key)