On April 12, 1981, the first space shuttle, Columbia, lifted off from Cape Canaveral, Florida, on its maiden flight into space. The shuttle was powered by three liquid-fueled engines and a pair of giant strap-on, solid-fuel boosters. The basic principle that makes it work is exactly the same as that behind a simple firework rocket or a balloon that zooms across the room when you let go of its neck. It is the principle of action and reaction.
Leonardo da Vinci’s Last Supper, one of the greatest achievements of Western art, has probably suffered more damage than any other great work. The 12 foot high mural was finished in the late 1490s and within 20 years paint was already flaking off. By 1587, the painting was described as “half-ruined”.
The technique for making thin, flat window glass was perfected in Normandy, France, in the 14th century. Known as crown glass, each piece was blown by a craftsman. An accomplished glass-blower could make only about a dozen windows in a day, making medieval window glass an expensive luxury.