Before radar, Britain built enormous concave concrete sound mirrors along the coast so listeners could hear distant aircraft engines and estimate their direction.

Jacques de Vaucanson's eighteenth-century automaton duck flapped, drank, ate grain, and appeared to excrete it, astonishing audiences even though the digestive trick was an illusion.

Italy's Villa Girasole was built on a circular rail system so the entire two-wing house could slowly turn around a central tower and face the sun.

New York's pneumatic mail network shot canisters beneath city streets, and postal lore records a cat being sent through a tube during an early demonstration before emerging alive.

Detroit's J.W.

London's Rolling Bridge is made from eight hinged sections that lift and curl until the walkway becomes an octagonal wheel, opening the canal passage without swinging sideways.

In 1950, a young circus elephant named Tuffi panicked during a publicity ride on Wuppertal's suspended railway, broke through the car, and fell into the river below.

The Haskell Free Library and Opera House was deliberately built across the Canada–United States boundary.

A Massachusetts engineer built a summer house with walls and furniture made from layers of varnished newspaper.

In 1999, engineers lifted the 4,830-ton Cape Hatteras Lighthouse and moved it 2,900 feet away from an eroding shoreline.