Elsewhere I posted "give me the details of a single glacial stone that is in its natural placement, or reliably recorded before being humanly moved, on Salisbury Plain. A bet: I'll give £100 to your favourite charity if you can and £100 to mine if you can't, from you."
The world's leading expert on Salisbury Plain Glacial Erratics has refused to take the bet but insists there are lots of them.
My response: "Put up or shut up"
If you know better claim the money.