Smoke-absorbing lamp [Photo/Xinhua]

Two 2,000-year-old bronze lamps that can "swallow" smoke were found in the tomb of "Haihunhou" (Marquis of Haihun) last year.

The lamps are in the shape of a goose catching a fish in its mouth. The light is attached to the fish. Smoke emitted during the burning of wax can enter the bird's body via an intake on the fish, travel through its neck and be dissolved by water stored in its hollow belly.

Apparently, people early in Han Dynasty began to design environment-friendly household objects.