Untimely inventions

In 1834, Charles Babbage (1792-1871) designed the Analytical Engine, the precursor of the computer. He was unable to obtain funding for it from the government, who thought it would be worthless.

The first fax process was patented in 1843 by Alexander Bain, but fax machines went into service only in 1964. In 1888, Frank Sprague completed an electric railway, but electric locomotives were introduced only in 1895. Eugene Ely landed a plane on a boat in 1911, but aircraft carriers weren't perfected for another 20 years.

The first parachute jump was made from a hot air balloon by Andre-Jacques Garnerinthe in France in 1793. Leonardo da Vinci made detailed sketches of parachutes in 1485. He also sketched studies for a helicopter, a tank and retractable landing gear. The first helicopter that could carry a person was flown by Paul Cornu in 1907. Tanks were first used during World War One in Cambrai, France in 1917. The first airplane with retractable landing gear was built in 1933. Da Vinci also suggested underwater breathing methods. Jacques-Yves Cousteau and Emile Gagnon introduced scuba diving only in 1943, 458 years later.

Although Alexander Fleming discovered penicillin in 1928, it was only in 1938 that Howard Florey and Ernst Chain found a way to produce it, demonstrating it only in 1942.

Adolph Fick first suggested contact lenses in 1888, and although two companies manufactured lenses out of glass, it wasn't until 1948 when Kevin Tuohy invented the soft plastic lens.

Bar codes were invented by Bernard Silver and Norman Woodland in 1948. Their system used light to read a set of concentric circles, but they had to wait two decades before the advent of computers and lasers made their system practical. (However, the bar code system in use today is the Universal Product Code, introduced by IBM in 1973. The first bar coded item sold was a pack of gum in 1974.)
Modern technology... well, somewhat...

Heron of Greece suggested the used of steam power in 50 BC. But the leaders of the day thought that it would cause unemployment which may lead to unrest and the invention ran out of steam. Steam technology known to the Chinese by 800 BC. Plato, in his Hero of Alexandria of 150 BC, mentioned some 70 steam inventions. But the steam engine reappeared again only in 1698 when Thomas Savery invented a steam pump. The first practical steam engine was the atmospheric machine of Thomas Newcomen in 1701. It was used to operate pumps on coal mines. In 1769, Nicolas Joseph Cugnot drove his steam tractor, officially the first known motorcar, down a street in Paris. In 1804, English inventor Richard Trevithick introduced the steam locomotive in Wales. In 1815, George Stephenson built the world's first workable steam locomotive.

The computer was launched in 1943, more than 100 years after Charles Babbage designed the first programmable device. Babbage dropped his idea after he couldn't raise capital for it. In 1998, the Science Museum in London, UK, built a working replica of the Babbage machine, using the materials and work methods available at Babbage's time. It worked just as Babbage had intended.

Thomas Edison invented the phonograph in 1877. Peter Carl Goldmark invented the LP record in 1948. The Compact Disc was invented by Joop Sinjou and Toshi Tada Doi in 1979. It took the CD fifteen years to replace the LP.

The first true aircraft carrier, HMS Furious, was converted from a battlecruiser into a flush-deck aircraft carrier in 1917, and it was the prototype of all flat-tops. The first aircraft carriers designed from scratch were HMS Hermes and IJN Hosho, which both were launched in 1920. HMS Furious is the only aircraft carrier which did combat operations in both World Wars. She was scrapped in 1948.

Douglas Engelbart experimented in the 1960's with light pens and steering wheels before deciding on a mouse for computer use.