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The History of The Clocks

The History of The Clocks. CGULS 9209005 雷雅晴 9209016 羅庭芳 9209029 楊雅君. The etymology --- origin of the word Clock. Sundial Water Clocks Watches Bell Clocks. The origin of the word. Clokke = Middle English Clocca = Medieval Latin Cloc = Celtic and Old Irish

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The History of The Clocks

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  1. The History of The Clocks CGULS 9209005 雷雅晴 9209016 羅庭芳 9209029 楊雅君

  2. The etymology --- origin of the word Clock • Sundial • Water Clocks • Watches • Bell • Clocks

  3. The origin of the word • Clokke = Middle English • Clocca = Medieval Latin • Cloc = Celtic and Old Irish • Clugge = Old English • Glocka = Old High German

  4. The Sands of Time ( Sand Clock ) • glass vessel which has two compartments • used by navies 1. as a timekeeper 2. to find the speed of the ship

  5. Sundial --- Shadow Clock • A vertical stick, gnomon, or obelisk that casts a shadow is a Sundial • "The Equation of Time" tell Apparent sun time, while your clock tells Mean Solar Time

  6. ALARM CLOCK • The Candle was used as an alarm clock by placing a nail into the wax, whenever the candle wax melted down to the nail, then the nail would fall into a tin pan and make a noise.

  7. The alarm typically had a cam that rotated every 12 hours. There was a notch into which a lever would fall, releasing a train of gears that engaged a hammer, which repeatedly hit a bell.

  8. Pendulum Clock • In 1583 Galileo demonstrated that successive beats of a pendulum always take place in the same length of time, regardless of the distance through which the "pendulum do swing". • The wheel or ring that replaced the verge and foliot escapement is called a Balance Wheel. • Huygen's design used a recoil escapement with an escape wheel and anchor with pallets called an Anchor Escapement.

  9. The Pendulum has a natural frequency that is independent of amplitude and the frequency does not depend on the weight of the pendulum, only its length and the acceleration of gravity. • George Grahamn of London, England in about 1720 modified the anchor escapement to eliminate recoil, creating the Deadbeat Escapement.

  10. Electrical Clocks ------Battery Clocks • In 1840 the first Battery clock used an electrical impulse to operate the dials of a centrally located master clock. • in 1906 the first self contained battery driven clock was invented.

  11. Electrical Clocks---- Synchronous Electric Motor Clock • The synchronous electric motor came into use in 1918. • Patented by Henry Ellis Warren in 1916.

  12. Electrical Clocks------ Quartz Clocks • The piezoelectric effect was discovered by the Curie brothers in 1880 • The first Quartz Crystal was applied in a clock in 1929.This clock can have an accuracy of one second every 10 years.

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