In fact, I don’t think I have ever seen anything even remotely close to this:
Sadly, I was in a hurry to catch a train, but there are many questions I’d like to ask. Number one among those: how important is it to keep the stick vertical? I assume a tube with such a high aspect ratio between its length and diameter is in great danger of bending.
Update on September 6: He was out there again today, so I stopped to talk with him and he showed me the device. He also demonstrated it will NOT bend! It‘s made out of an extremely heavy, extremely thick PVC plastic, and it‘s attached to a compressor that pumps water to the top.