The DNA of a battle that helped turn the tide of a war going horribly wrong for America lay buried just six inches below the surface in a Kent County cornfield.

For nearly two centuries, the musket balls, canister shot and other artifacts from intense fighting at Caulk's Field waited to tell the story of a sweltering August night in 1814, when militiamen sprang a trap on a British raiding party bent on destruction.

How did the citizen-soldiers best their battle-tested foes at Caulk's Field?...