Timeline of time measurement inventions


The timeline of time measurement inventions is a chronological list of particularly important or significant technological inventions relating to timekeeping devices and their inventors, where known.

Note: Dates for inventions are often controversial. Sometimes inventions are invented by several inventors around the same time, or may be invented in an impractical form many years before another inventor improves the invention into a more practical form. Where there is ambiguity, the date of the first known working version of the invention is used here.

Classical antiquity

  • c. 3500 BC - Egyptian obelisks are among the earliest shadow clocks.[1]
  • c. 1500 BC - The oldest of all known sundials, dating back to the 19th Dynasty.[2]
  • c. 500 BC - A shadow clock is developed similar in shape to a bent T-square.[3]
  • 3rd century BC - Berossos invents the hemispherical sundial.[4]
  • 270 BCE - Ctesibius builds a water clock.

Medieval era

  • 11th century - Sets of hourglasses were maintained by ship's pages to mark the progress of a ship during its voyage
  • 11th century - Large town clocks were used in Europe to display local time, maintained by hand
  • 1335 - First known mechanical clock, in Milan
  • 1502 - Peter Henlein builds the first pocketwatch
  • 1522 - The Portuguese navigator Ferdinand Magellan used 18 hourglasses on each ship during his circumnavigation of the globe.[5]

Modern era


  1. ^ "Sundial". Encyclopædia Britannica. Retrieved April 4, 2008.
  2. ^ "One of world's oldest sun dial dug up in Kings' Valley, Upper Egypt". ScienceDaily. 14 March 2013. Retrieved 10 May 2021.
  3. ^ Barnett 1999, p. 18.
  4. ^ Dolan 1975, p. 34.
  5. ^ Bergreen 2003, p. 53.
  6. ^ "A Walk Through Time - Ancient Calendars". NIST. Retrieved 15 May 2021.
  7. ^ Landes 1985, p. 220.
  8. ^ Marrison 1948, p. 538.


  • Barnett, Jo Ellen (1999). Time's Pendulum: From Sundials to Atomic Clocks, the Fascinating History of Timekeeping and How Our Discoveries Changed the World (1st ed.). San Diego: Harcourt Trade Publishers. ISBN 978-01560-0-649-1.
  • Bergreen, Laurence (2003). Over the Edge of the World: Magellan's Terrifying Circumnavigation of the Globe. New York: Morrow. ISBN 978-0-06-621173-2.
  • Dolan, Winthrop W. (1975). A Choice of Sundials. Brattleboro, Vermont: The Stephen Greene Press. OCLC 471181086.
  • Landes, David S. (1985). Revolution in Time: Clocks and the Making of the Modern World. Cambridge, Massachusetts: Harvard University Press. OCLC 29148451.
  • Marrison, Warren A. (1948). "The Evolution of the Quartz Crystal Clock". Bell System Technical Journal. New York: AT&T. 27 (3): 510–588. doi:10.1002/j.1538-7305.1948.tb01343.x. OCLC 10999639. S2CID 88503681.