The History of Timekeeping

Sundial

Clepsydra

Astrolabe

Candle Clock

Sandglass

Mechanical Clock

Spring-Driven Clock

Pendulum Clock

Quartz Clock

Cesium Atomic Clock

 

Quartz Clock
  The initial quartz clock was invented in 1927 by Warren A. Marrison and J.W Horton. Quartz crystals vibrate anywhere from thousands to millions of times every second. This happens because of the different electric fields the quartz crystal is faced with. In a watch, the electric current produced from the battery causes this vibration. The high frequency is reduced to a lower frequency that is transferred through a coil. It’s magnet then alternates back and forth and moves a small pinion that turns the crystal vibration into a mechanical movement. Before quartz clocks, a second had been defined as 1/86,400 of an average solar day (the average amount of time it took for one rotation of the Earth). However, new knowledge of a second helped scientists discover that the Earth’s rotation was an unreliable tool used to tell time. This new discovery was not altered in quartz clocks because of the change that took place in quartz crystals after long periods of time. In the quartz crystal, their was either a change in the back and forth motion or the vibrations. This was a result of either temperature changes, reoccurring effects of the vibrations, or the impurities in the quartz. Back then, these clocks were very space consuming. Nowadays, quartz clocks have advanced so much that they are found in all types of things such as calculators and computers. Quartz clocks are presently the most common tool used for timekeeping.