Events relating to inventions and discoveries

Abraham Darby at Coalbrookdale discovers the use of coke in the smelting of pig iron

Fahrenheit perfects the mercury thermometer and decides on a 180-degree interval between the freezing and boiling points of water

The British government offers a massive £20,000 prize for a chronometer capable of keeping accurate time at sea

English maker of telescopes John Hadley designs the instrument which evolves into the standard sextant used at sea

John Kay, working in the Lancashire woollen industry, patents the flying shuttle to speed up weaving

Swedish astronomer Anders Celsius proposes 100 degrees between the freezing and boiling points of water

Franklin publishes his design for an improved stove in Account of the New Invented Pennsylvania Fire Place

Monsieur Passemont constructs in Paris a millennium clock which can record the date in any year up to AD 9999

John Harrison's fourth chronometer is only five seconds out at the end of a test journey from England to Jamaica

James Watt ponders on the inefficiency of contemporary steam engines and invents the condenser

Lancashire spinner James Hargreaves conceives the idea of the spinning jenny, with multiple spindles worked from a single wheel

Pierre le Roy's chronometer, as accurate as Harrison's and cheaper to construct, is set to become the standard model

French inventor Nicolas-Joseph Cugnot successfully tests a steam wagon, probably the first working mechanical vehicle

English entrepreneur Richard Arkwright adds water power to spinning by means of the water frame

Samuel Crompton perfects the mule, a machine for spinning that combines the merits of Hargreave's jenny and Arkwright's water frame

French paper manufacturer Joseph Montgolfier sends a hot-air balloon 3000 feet (1000m) into the air, in front of a crowd in Annonay

Ten days after the first human ascent in a hot-air balloon the feat is repeated, again in Paris, in a version lifted by hydrogen

Louis XVI watches through his telescope the first balloon flight with living passengers – a sheep, a cock and a duck

A hot-air balloon rises from a Paris garden, carrying the first human aeronauts – Pilàtre de Rozier and the marquis d'Arlandes

Benjamin Franklin, irritated at needing two pairs of spectacles, commissions from a lens-grinder the first bifocals

English ironmaster Henry Cort patents a process for puddling iron which produces a pure and malleable metal

French inventor Claude Chappe develops a hilltop signalling system, for which he coins the words telegraph and semaphore

Eli Whitney invents the cotton gin, enormously speeding up the process of separating cotton fibres from the seeds

A Scottish clergyman, Alexander Forsyth, invents the percussion cap to help in his pursuit of wildfowl

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