Timeline of time measurement technology
Timeline of time measurement technology
- 270 BC - Ctesibius[?] builds a popular water clock[?]
- 46 BC - Julius Caesar and Sosigenes develop a solar calendar with leap years
- 1502 - Peter Henlein[?] builds the first pocketwatch[?]
- 1582 - Pope Gregory XIII, Aloysius Lilius, and Christopher Clavius[?] introduce a Gregorian calendar with an improved leap year system
- 1656 - Christian Huygens builds the first accurate pendulum clock
- 1676 - Motion works and minute hand introduced by Daniel Quare[?]
- 1680 - Second hand introduced
- 1737 - John Harrison presents the first stable nautical chronometer, thereby allowing for precise longitude determination while at sea
- 1928 - Joseph Horton[?] and Warren Morrison[?] build the first quartz crystal oscillator clock[?]
- 1946 - Felix Bloch and Edward Purcell[?] develop nuclear magnetic resonance
- 1949 - Harold Lyons[?] develops an atomic clock based on the quantum mechanical vibrations of the ammonia molecule
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