Scientific revolutions

Andreas Vesalius publishes De Humani Corporis Fabrica, rewriting the map of the human body.

He finds over 200 errors in Galen's ancient texts — including the discovery that the human jawbone is a single bone, not two as Galen claimed from dissecting apes.

De Humani Corporis Fabrica Libri Septem is a set of books on human anatomy written by Andreas Vesalius (1514–1564) and published in 1543. It was a major advance in the history of anatomy over the long-dominant work of Galen, and presented itself as such.

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Galileo Galilei points his telescope at Jupiter and discovers four moons circling the planet.

He names them the 'Medicean Stars' to flatter his patron, Cosimo II de' Medici — a savvy career move that secures him a court position in Florence.

The Galilean moons, or Galilean satellites, are the four largest moons of Jupiter. They are, in descending-size order, Ganymede, Callisto, Io, and Europa. They are the most readily visible Solar System objects after Saturn, the dimmest of the classical planets; though their closeness to bright Jupiter makes naked-eye observation very difficult, they are readily seen with common binoculars, even under night sky conditions of high light pollution. The invention of the telescope allowed astronomers to discover the moons in 1610. Through this, they became the first Solar System objects discovered since humans have started tracking the classical planets, and the first objects to be found to orbit any planet beyond Earth.

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Robert Hooke publishes Micrographia, the first scientific bestseller illustrated with detailed drawings from a microscope.

His fold-out engraving of a flea — so large it spans two full pages — is the talk of London, and Samuel Pepys stays up until 2 a.m. reading it.

Micrographia: or Some Physiological Descriptions of Minute Bodies Made by Magnifying Glasses. With Observations and Inquiries Thereupon is a historically significant book by Robert Hooke about his observations through various lenses. It was the first book to include illustrations of insects and plants as seen through microscopes.

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Benjamin Franklin flies a kite in a thunderstorm and draws an electrical charge from a storm cloud.

Franklin never actually describes being struck by lightning himself — his account carefully notes the charge travelling down a wet hemp string to a key, not to his hand.

The kite experiment is a scientific experiment in which a kite with a pointed conductive wire attached to its apex is flown near thunder clouds to collect static electricity from the air and conduct it down the wet kite string to the ground. The experiment was first proposed in 1752 by Benjamin Franklin, who reportedly conducted the experiment with the assistance of his son William. The experiment's purpose was to investigate the nature of lightning and electricity, which were not yet understood. Combined with further experiments on the ground, the kite experiment demonstrated that lightning and electricity were the result of the same phenomenon.

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Joseph Priestley heats red mercuric oxide and collects a mysterious gas that makes a candle burn fiercely bright.

He calls it 'dephlogisticated air' and cheerfully breathes some himself, noting it feels 'peculiarly light and easy' in his chest.

Joseph Priestley's isolation of 'dephlogisticated air' overturns centuries of chemical theory and lays the groundwork for modern chemistry.

Antoine Lavoisier publishes his Elementary Treatise on Chemistry, naming oxygen and demolishing the phlogiston theory of fire.

His wife Marie-Anne illustrates the book herself and translates rival chemists' English papers for him — making her an uncredited co-architect of the chemical revolution.

Traité élémentaire de chimie is a textbook written by Antoine Lavoisier published in 1789 and translated into English by Robert Kerr in 1790 under the title Elements of Chemistry in a New Systematic Order containing All the Modern Discoveries. It is considered to be the first modern chemical textbook.

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Michael Faraday discovers that moving a magnet through a coil of wire generates an electric current.

When a politician asks what practical use his discovery has, Faraday reportedly replies, 'What use is a newborn baby?' — though the exchange may have been with Prime Minister Gladstone years later.

Electromagnetic induction or magnetic induction is the production of an electromotive force (emf) across an electrical conductor in a changing magnetic field.

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Gregor Mendel publishes his laws of heredity, derived from eight years of breeding pea plants in a monastery garden.

His paper is read aloud at two meetings of the Brünn Natural History Society and then largely ignored for 34 years, until three scientists independently rediscover it in 1900.

Gregor Mendel's pea-plant experiments reveal the mathematical laws governing how traits are inherited, founding the science of genetics.

Wilhelm Röntgen accidentally discovers a mysterious ray that passes through flesh and darkens photographic plates.

He takes an X-ray of his wife Bertha's hand — upon seeing the image of her bones and wedding ring, she reportedly says, 'I have seen my own death.'

Wilhelm Röntgen's accidental discovery of X-rays gives medicine its first tool for seeing inside the living human body without surgery.

Alan Turing publishes his paper describing a theoretical 'universal computing machine' that can simulate any algorithm.

The paper is written to solve a pure logic puzzle posed by David Hilbert — Turing invents the concept of a programmable computer almost as a side effect.

A Turing machine is a mathematical model of computation describing an abstract machine that manipulates symbols on a strip of tape according to a table of rules. Despite the model's simplicity, it is capable of implementing any computer algorithm.

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