More recent archaeological hypotheses have them transporting the bluestones with supersized wicker baskets on a combination of ball bearings and long grooved planks, hauled by oxen.
It's like a V-shaped trench. I'm imagining like there's a ball bearing, and it's like, and it can only go forward in that trench or back. And it goes forward. - Right.
Lubricants such as silicone oils can be included in them, to make the damaged surfaces of ball-bearings that have run out of oil more slippery, so that they are not scratched too rapidly.
But slowly but surely, you see the whittling down of German parts and the tool and die industry and the ball bearings and all these things that suffer from the bombing.