About the Book
Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Pages: 96. Chapters: Sundial, Leap second, Timeline of time measurement technology, Time standard, T, Diptych, Gnomon, International Earth Rotation and Reference Systems Service, Primary time standard, Long-term stability, Proper time, History of timekeeping devices, Time in physics, Water clock, Equation of time, Tropical year, Old Style and New Style dates, House of Keglevi, Simon Newcomb, Timekeeping on Mars, Hourglass, Time signal, Time discipline, System time, Hindu units of measurement, Telechron, History of sundials, Dual dating, Louis Essen, William Willett, Time ball, Ship's bell, Tide, Clock drift, Torsion pendulum clock, Fully automatic time, Time Matters, Analemmatic sundial, Winter count, Horology, History of timekeeping devices in Egypt, Hammond Clock Company, William Markowitz, Charles F. Dowd, Merkhet, Cover date, Cranmer Park, Jack Robinson, Geochron, 365, Visual schedules, International Time Bureau, MarsDial, Slovene months, Deal Timeball, Business hours, Moondial, Dialling, Time domain, Circa, Date and time notation, Timekeeper, Chronometry, Star clock, Apparent sun, Horometry. Excerpt: For thousands of years, devices have been used to measure and keep track of time. The current sexagesimal system of time measurement dates to approximately 2000 BC, in Sumer. The Ancient Egyptians divided the day into two 12-hour periods, and used large obelisks to track the movement of the Sun. They also developed water clocks, which were probably first used in the Precinct of Amun-Re, and later outside Egypt as well; they were employed frequently by the Ancient Greeks, who called them clepsydrae. The Shang Dynasty is believed to have used the outflow water clock around the same time, devices which were introduced from Mesopotamia as early as 2000 BC. Other ancient timekeeping devices include the candle clock, used in China, Japan, ...
