I'm walking with Sheleen in a clean, bare building, like an airport. We pass down a long ramp, sloping downward, with a waist-high wall on our right, with a railing. Over the wall is a surface that curves, being almost horizontal where it meets the wall on our side, but becoming vertical on the other side, where it descends to meet the floor, one story or so down.

I've dropped something small, perhaps a cell phone, and it sits about halfway down the surface. I climb over the wall and start climbing down to retrieve it, relying on the friction of the surface, but before I get there it becomes too difficult, so I slip down and stand on the floor, looking up at the surface. I thought it would be easier to climb up the wall and get the phone in a controlled fashion, but it's harder than I thought.

Then I notice that there are little holds set into the wall, as if especially for this purpose. They are marked with which hand and foot should be placed on them, like a preplanned route to climb out.