The Mississippi: The River Gives Up Its Secrets

The drought has reduced parts of the mighty Mississippi to a slow, shallow stream, stalling barge traffic amid rocks and sandbars. But as the water recedes, the river bottom emerges, providing clues to a lost past. On an ugly beach of sand and clay in Arkansas, just downstream from Memphis, archaeologists have struck what they consider gold: large chunks of riverboats built in the late 1800s and long buried in silt.

The discoveries include parts of a 200-ft. stern-wheel steamboat, a 175-ft. wooden coal barge and another 140-ft. wooden barge. These relics excite historians because no large boats of the era,...