Science
Discoveries and the scientific method.
Category: Knowledge
- c. 585 BCEThales and the eclipse of 585 BCE (traditional)
Herodotus says Thales of Miletus predicted the eclipse that halted a battle between Lydians and Medes in 585 BCE. Many scholars reject the story. Aristotle calls Thales the first natural philosopher and says he held that everything comes from water.
- c. 550 BCEAnaximander writes on nature
Around 550 BCE Anaximander of Miletus is credited with the first Greek prose work on nature, of which one fragment survives. He proposes the apeiron, an unlimited source of all things, and is said to have published the first world map.
- c. 400 BCEDemocritus and atomism
Democritus of Abdera, building on Leucippus, teaches around 400 BCE that atoms and void are the only true realities. None of his works survive; we know him through fragments and reports, many from Aristotle.
- c. 400 BCEHippocrates and Greek medicine
Hippocrates of Kos (c. 460-370 BCE), "the Father of Medicine", gives his name to the Hippocratic Corpus, some seventy early medical works by several authors. The Hippocratic Oath was probably written after his death.
- c. 300 BCEEuclid and the Elements
Around 300 BCE Euclid works in Alexandria. His Elements gathers earlier mathematics into an ordered system of proofs. Little is known of his life, and later editors may have added material to the text.
- c. 287 BCEArchimedes of Syracuse
Archimedes is born about 287 BCE in Syracuse. His works include On the Sphere and Cylinder, On Floating Bodies, which states the principle of buoyancy, and the Method. The bath-and-"Eureka" story comes from Vitruvius, two centuries later.
- c. 285 BCEThe Library of Alexandria
The Library of Alexandria, part of the royal Mouseion, was probably founded under Ptolemy II, after Ptolemy I laid the groundwork. Its scholars include Zenodotus, Callimachus and Eratosthenes. Estimates of its holdings range from 40,000 to 700,000 scrolls.
- c. 280 BCEAristarchus proposes a heliocentric cosmos
Aristarchus of Samos, who observed the solstice of 280 BCE, proposes that the Sun is fixed and the Earth orbits it. His book is lost; Archimedes' Sand Reckoner reports the idea. Plato, Aristotle and Ptolemy prefer an Earth-centred cosmos.
- c. 246 BCEEratosthenes measures the Earth
After Ptolemy III comes to the throne in 246 BCE, Eratosthenes of Cyrene is called to Alexandria as chief librarian. He measures the Earth's circumference from shadows at Syene and Alexandria, with a result perhaps within 1% of the truth.
- 127 BCEHipparchus and the precession of the equinoxes
Hipparchus of Nicaea is credited with discovering the precession of the equinoxes in 127 BCE, at a rate of not less than 1 degree a century. He is known as the father of trigonometry and compiled a star catalogue, perhaps in 135.
- c. 100 BCEThe Antikythera mechanism
A hand-cranked analogue computer of the late 2nd or early 1st century BCE predicts the Sun, Moon and eclipses, and tracks the Olympiad cycle. Sponge divers recover it from a Roman wreck at Antikythera in 1900-1901. Its date and origin are debated.
- c. 808Hunayn ibn Ishaq translates Galen into Arabic
Hunayn ibn Ishaq, a Nestorian Christian physician in Baghdad (born c. 808-809, died 873 or 877), translates 129 works of Galen and others from Greek via Syriac into Arabic. His Ten Treatises on the Eye is the first known systematic work on ophthalmology.
- c. 820Al-Khwarizmi writes the book that names algebra
Around 820 Muhammad ibn Musa al-Khwarizmi writes in Baghdad his Compendious Book on Calculation by Completion and Balancing, classing quadratic equations into six types. The word "algebra" comes from its title. Robert of Chester translates it into Latin in 1145.
- c. 865Al-Razi, physician and critic of Galen
Al-Razi (born 864 or 865 at Ray, died 925 or 935) heads hospitals at Ray and Baghdad. He writes on smallpox and measles and in Doubts about Galen challenges humoral theory. His al-Hawi and Liber Almansoris reach Latin in 1279 and c. 1180.
- 1011Ibn al-Haytham writes the Book of Optics
Ibn al-Haytham (c. 965-c. 1040) writes the seven-book Book of Optics in 1011-1021, arguing that sight occurs when light enters the eye, not through rays sent from it, with experimental arguments. Its Latin version, De aspectibus, appears c. 1200 and is printed in 1572.
- 1025Avicenna completes the Canon of Medicine
Avicenna completes the Canon of Medicine in 1025 at Hamadan: five books, from principles and some 800 simple drugs to diseases and 650 compound drugs. Gerard of Cremona is credited with the Latin version. It is printed in 1472 and used in universities for centuries.
- 1027Avicenna publishes the Book of Healing
Begun in 1014 and published in 1027, Avicenna's Book of Healing is an encyclopedia in four parts: logic, natural sciences, mathematics and metaphysics. A partial Latin version, Sufficientia, appears some fifty years later and influences Albertus Magnus and Aquinas.
- c. 1030Al-Biruni completes his study of India
Al-Biruni (973-c. 1050), taken to Ghazni in 1017 and soon on Mahmud's campaigns in India, completes his Kitab al-Hind around 1030. His earth-radius measurement at Nandana, by horizon dip, survives; its accuracy depends on a cubit length that is unclear.
- c. 1077Constantine the African translates Arabic medicine
Constantine the African, a monk at Monte Cassino (1077 by one account), translates Arabic medical works into Latin, among them the Pantegni and Viaticum. He often omitted the authors' names, so Renaissance scholars called him a plagiarist. He died before 1098.
- c. 1126Adelard of Bath brings Arabic science into Latin
Adelard of Bath, who travelled in Sicily and the East, is back in the West by 1126. He translates al-Khwarizmi's astronomical tables and makes the oldest surviving Latin Euclid, from an Arabic text. His death is placed anywhere from c. 1142 to c. 1160.
- 1154Al-Idrisi completes the Tabula Rogeriana
In 1154, weeks before Roger II of Sicily dies, al-Idrisi finishes at Palermo a world atlas that took about 15 years: 70 sectional maps and a silver planisphere, with south at the top. The originals were destroyed in a 1160 rebellion; the oldest copy dates to about 1300.
- 1202Fibonacci writes the Liber Abaci
Leonardo of Pisa (Fibonacci), who studied arithmetic at Bugia in North Africa, writes the Liber Abaci in 1202, helping bring Hindu-Arabic numerals and place-value notation to Europe. A revised version follows in 1228. Adoption was slow, widespread only by the late 16th century.
- c. 1406Jacopo d'Angelo translates Ptolemy's Geography into Latin in Florence
Jacopo d'Angelo, a pupil of Chrysoloras, translates Ptolemy's Geography in Florence (c. 1406-07), opening its coordinate-based map-making to Latin readers. The first printed edition with maps followed in Bologna in 1477.
- c. 1450Fra Mauro draws his world map in Venice, drawing on Marco Polo
The Camaldolese monk Fra Mauro makes a large world map at San Michele in Isola, Venice. Its Asian annotations draw on travellers such as Marco Polo and Niccolò de' Conti.
- 1475Toscanelli sets up a gnomon in Florence Cathedral
Astronomer Paolo dal Pozzo Toscanelli opens a hole in the cathedral's dome, about 91 metres above the floor, to cast a meridian line for observing the sun around the summer solstice.
- 1482Erhard Ratdolt prints the first edition of Euclid's Elements
The printer Erhard Ratdolt, working in Venice, issues the first printed edition of Euclid's Elements, solving the problem of reproducing geometric diagrams in print.
- c. 1490Leonardo draws the Vitruvian Man
Leonardo draws a male figure inscribed in a circle and a square, a study of ideal human proportions, probably in Milan.
- 1494Luca Pacioli's Summa de arithmetica is printed in Venice
Luca Pacioli's Summa de arithmetica, printed in Venice, is the first published description of double-entry bookkeeping. Its fame brings him to Ludovico Sforza's court in Milan, where he works with Leonardo da Vinci.
- 1502Leonardo maps the town of Imola
Working for Borgia, Leonardo draws a plan of Imola seen from directly above, a method unusual at the time. Most sources place it in autumn 1502.
- c. 1510Leonardo dissects human bodies with Marcantonio della Torre at Pavia
Leonardo da Vinci works with the anatomist Marcantonio della Torre at Pavia on human dissections, planning a treatise that was never published. Della Torre died of plague in 1511. Some drawings may date to 1513.
- 1543Copernicus publishes De revolutionibus
A heliocentric model of the cosmos appears in print.
- June 1543Vesalius publishes De humani corporis fabrica in Basel
Andreas Vesalius, aged 28 and formerly professor of anatomy at Padua, publishes his illustrated De humani corporis fabrica, printed by Oporinus in Basel. Based on his own dissections, it corrects about 300 of Galen's errors.
- November 1572A new star challenges Aristotle's unchanging heavens
A new star appears in early November 1572 and outshines Jupiter by the 11th. In De nova stella (1573), Tycho Brahe compares observations, including Jerónimo Muñoz's, to show it lies beyond the Moon, contradicting the Aristotelian view of an unchangeable realm of stars.
- 1583Rudolf II moves the imperial court to Prague
In 1583 Rudolf II moves his court from Vienna to Prague, which becomes an imperial capital. He supports astronomers such as Tycho Brahe and Johannes Kepler and gathers a major collection of art and curiosities.
- January 1610Galileo observes the Moons of Jupiter
Telescope observations show bodies orbiting another planet.
- March 13, 1610Galileo publishes Sidereus Nuncius and dedicates it to the Medici
Published in Venice on 13 March 1610, Galileo's Sidereus Nuncius is dedicated to his former pupil Cosimo II de' Medici. He names Jupiter's four moons after the Medici brothers, which helps him win a Medici court post.
- 1620Bacon publishes the Novum Organum
Francis Bacon's Novum Organum (1620), "New Instrument", is a rival to Aristotle's Organon. It rejects syllogistic logic for induction and says Aristotle made his natural philosophy "a mere slave to his logic". It also lists four "idols" that distort thought.
- February 1632Galileo publishes the Dialogue on the Two Chief World Systems
Printed at Florence in February 1632, Galileo's Dialogue pits Simplicio's Aristotelian and Ptolemaic views against Salviati, who cites the novae of 1572 and 1604 and sunspots against unchanging heavens. In 1633 he is found "vehemently suspect of heresy" and the book banned.
- July 5, 1687Newton's Principia
Newton publishes the laws of motion and universal gravitation.
- July 20, 1969Apollo 11 lands on the Moon
Armstrong and Aldrin become the first humans on the lunar surface.