Ice Tube

It was pretty cold last night with the temperature getting down to at least minus 5. The result is this weird looking thing. We left an old frying pan out under the apple tree, with water in it for the birds. Something happened overnight to cause this hollow tube of ice to form on the thin icy crust which formed on the surface. I can only guess that it may have been caused by water dripping down from the tree, rebounding off the surface and freezing as it did, over and over until it formed this strange thing.
Latest report: 1pm and the THING just sank under its own weight as the surface layer melted.