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The Evolution of Time Telling
Clocks
Prehistoric man:
Phases of the moon
Observation of the stars
The Big Dipper and the North Star
Sunrise, sunset
Changes in the seasons
What is a second?
300 BC: sexagesimal division
16th century: seconds on clocks
1952: ephemeris seconds
1955: caesium seconds
9,192,631,770 Hz
Coordinated Universal Time (UTC)
International Atomic Time (TAI)
Atomic clocks deviate only 1 second in about 20 million years.
Universal Time (UT1)
Also known as astronomical time, refers to the Earth's rotation.
Time Zones
Region on earth that has a uniform standard time
40 time zones on land
Earliest and latest time zones are 26 hours apart
Any given calendar date exists at some point on the globe for 50 hours
Past: Sundial
From the 2nd millennium BC.
The length and position of a shadow cast by a vertical stick caused by the movement of the sun through the sky. It is an estimate of time because it is not accurate due to the variation of the sun’s path during the seasons.
1400-1000 B.C
Water Clocks (Clepsydra): 1400 BC Egypt
Measures time by the amount of water that drips from a tank.
Candle Clocks 1000 B.C
As the candle burned it would pass a marker which indicated a certain length of time.
First alarm clock
6th Century
Incense Clocks
First used in China
Weights tied with threads were attached to incense sticks
at every interval as the stick would burn out the weight
drops into a metal pan making a sound
13th - 14th Century
European Clocks (mechanical Clocks): 13th-14th century
First clocks in European cathedrals did not have faces and were made to “chime” hourly.
Foliot = Primitive version of the pendulum used to regulate the oscillation of the timing bar
16th-17th Century
Pendulum Clocks 16th
Rolling Ball Clocks 17th Century
Present
The Quartz (Analog Clock)
Invented Jan.1 1927 by Warren Marrison and J.W. Horton
Works by having a battery send electric currents to cause a vibration
Most common type of clock used for time keeping
Present
The Atomic Clock
Invented Jan. 1 1949 from production of many scientists in England
Uses electromagnetic waves to track the time
Used in business & science due to how accurate it is
Future of Clocks: Year 2154
Timex and Core 77
Design Competition
Commemorate 150 years of crafting and time keeping
TX54 designed by David Tackas (USA)
Sublimex
Peter Martins (Portugal)
Timex Whisper
Joseph Ribic (USA)
Sticker Watch
Alexey Koptev (Russia)
Conclusion
Time regulates our daily lives
To accurately communicate with people all over the world
Farming, social structures, communication, and business
