Raw rubber is heated and extruded on to the drum, followed by successive layers of steel wires and strips as the tyre takes shape.

ECONOMIST: Re-inventing the wheel

She has made items from sculpture to body armour and is even looking at buildings, erected with computer-guided nozzles that deposit successive layers of concrete.

ECONOMIST: 3D printing

Composed of sedimentary rock (successive layers of coral, shells, sand, and other materials hardened over time), exploring Coral Castle is like wandering among a man's hopes which have been encrusted with disappointment.

BBC: The mystery of Florida��s Coral Castle