Stone Wall or Stone Pile?

Here we have a "temporary stone pile" and a stone wall under construction. Which one is which? Why?

The curve in the stone wall makes the answer easy. The first picture is the stone wall.

But if you look closely ,it is the ends that show the difference. The two sides of the wall and the pile are stacked in a similar manner, but the fill stones in the middle of the wall tell the story. In the stone wall the "chinkers" are laid flat so that gravity will help to hold them in place . In the temporary stone pile, the stones in the center are loosely piled in random fashion.

In both cases, left undisturbed these structures are pretty darned permanent!