Two worlds: one above, one below.

No one imagines the 9/11 dead walking around under the wreckage or the pit that replaced it. Most of them were pulverized before the towers hit the ground. These men and women do not walk. They went into the air and across the harbor, lodged on windowsills and in the cracks between bricks. We breathed them in.

But the firemen who died a few weeks ago right next to them -- where did they go? They climbed a ghost tower and died in smoke and fumes, not from fire. They burned inside out.

The miners may still be walking, dead but walking, as well as those who tried to rescue them. But they walk on different paths, and may walk for a thousand years, tapping the wall, trying to make contact.