Chaucer’s Astrolabe
![]() |
|
This image comes from a nineteenth century edition of Geoffrey Chaucer’s 1391 work “Treatise on the Astrolabe.” The drawing depicts the front of the instrument as described by Chaucer.
An astrolabe was a device used for the observation, measurement and calculation of numerous astronomical and astrological phenomena. For example, it could determine local latitude, identify stars and planets and determine their altitude, and determine the astrological location of the Sun and Moon in the particular Houses of the Zodiac.
The first astrolabes were developed during the late Hellenistic period. Islamic astronomers improved on and further developed these instruments, finding them very useful in determining such things as the dates for various religious holidays, as well as the direction of Mecca, necessary for performance of the five daily prayers. It is nearly certain that Chaucer based his Treatise on a comprehensive work on the device by the Persian-Jewish astrologer Mashallah ibn Athari dating from the late eighth or early ninth century and subsequently translated into Latin.
Images of Liberty and Power
- “New” Socialist Ideas in the 1848 Revolution
- A Monument to Frédéric Bastiat (1878)
- Abraham Lincoln as the “Federal Phoenix” (1864)
- Adam Smith and J.B. Say on the Division of Labour
- Algernon Sidney (1622-1683) and the Thomas Hollis Library of Liberty
- Althusius’s Schema for Politica
- Amagi Symbol: Liberty Fund’s Logo
- Ancient Romans
- Art of the Levellers
- Bach, Music, and Liberty
- Bentham’s Panopticon
- Biblical Figures
- Blackstone on Consanguity and Descent
- Brueghel, Taxes, and the Numeration of the People of Bethlehem (1566)
- Caricature of Richard Cromwell
- Cato and Republican Liberty
- Chaucer’s Astrolabe
- Cobden and the Anti-Corn Law League
- Coke’s Crest and Motto
- Coke’s splendid lineage
- Darwin’s diagram showing descent
- Declaration of the Rights of Man and of the Citizen
- Emancipation Proclamation
- Encyclopedic Liberty and Industry
- Engraving of John Toland
- Eugène Delacroix on Press Censorship during the Restoration (1814-1822)
- Frederick Douglass and Abolition
- Grotius on War and Peace
- Hobbes' Leviathan
- Images of the British Abolitionist Movement
- Jacques Callot, Hugo Grotius, and the Miseries of War in the 17th Century
- James Gillray on War and Taxes during the War against Napoleon
- Liberty slaying the Monsters of Tyranny and Oppression
- Lilburne quoting Coke on English Liberties at his treason trial (1649)
- Ludwig von Mises on Rationing in WW2
- Mises on Gresham’s Law and Ancient Greek Silver Coins
- Mises on Rationing and Price Controls in WW2
- Monuments to Free Trade: Bastiat and Cobden
- New Picture of Tocqueville in 1848
- New Playing Cards for the French Republic (1793-94)
- Ngrams and the Changing Vocabulary of Class Analysis in 19th Century Classical Liberal Thought
- Presidents Day and the Apotheosis of Washington
- Pufendorf and the Geometry of Morality
- Representative Women: An Image of Several Suffragists (1870)
- Roman Virtues
- Samuel warns the Israelites of the Dangers of Kings
- Shaftesbury’s Illustrations
- Shaftesbury’s Illustrations for Characteristicks (1732)
- Shakespeare
- Shays’s Rebellion
- The Divine Right of Kings or Regal Tyranny? (Hobbes and Lilburne)
- The First Colored Senator and Representatives
- The Gold Standard vs. Fiat Paper Money
- The People and the Ruling Elite in Caricatures (Wade and Daumier)
- The Seal of Florence
- The Spanish-American War and the Anti-Imperialism League (1902)
- The Très Riches Heures du Duc de Berry (1416)
- The Virtues
- Thomas Clarkson and the Abolition of the Slave Trade
- Thomas Hollis and John Locke
- Thomas Jefferson in the Cyclopedia
- Tocqueville and Bastiat on the 1848 Revolution in Paris
- Washington and Napoleon in their Study
- William Blake’s Illustrations of the Book of Job
- William Blake: An Introduction