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The History of
Timekeeping
Karen Isabelle Soares
Karla Natalia Queiroz
The History of Timekeeping - 2/13
Using the Sun
noon
sunset
sunrise
The History of Timekeeping - 3/13
Sundial Clocks
 Oldest type of clock
 Also called sun clocks
 The shadow points to a number
 Depend on the sun
The History of Timekeeping - 4/13
Water Clocks
 Around 4,000 B.C.
 Babylon, Egypt, India or China
 Water traveled through a tube
 Tell time during the night
The History of Timekeeping - 5/13
Dividing the Year into Months
 12 Moon cycles in a year
 Greeks divided the year in 12 months
The History of Timekeeping - 6/13
Dividing the Year into Days
 They divided the month in 30 days
 360 Days in a year
 360 Degrees in a circle
90°
180°
270°
360°
The History of Timekeeping - 7/13
Dividing the Day into Hours
 Egyptians and Babylonians
 Sunrise to sunset in 12 hours, sunset to sunrise also in 12 hours
 Whole day in 24 hours
+
The History of Timekeeping - 8/13
Minutes and Seconds
 Sumerian Sexagenary Sistem
The History of Timekeeping - 9/13
Mechanical Clocks
 Invented in medieval
Europe
 Common in churches
and monasteries
 “Clock” is from the Latin
word “clocca”
 One time-keeping hand
The History of Timekeeping - 10/13
Spring-powered Clocks
 Around 1500
 Became very popular among the rich
 Was the precursor to accurate timekeeping
The History of Timekeeping - 11/13
Pendulum Clocks
 Developed by Christian Huygens around 1656
 Pendulum clock had a minute hand
 Used to swing a lot (about 50 degrees)
 They stopped running after a while and had to be restarted
The History of Timekeeping - 12/13
Quartz Crystal Clocks
 Based on an electric property of the quartz crystal
 When you apply voltage, or electricity, and pressure, the quartz
crystal vibrates or oscillates at a very constant frequency.
 Very precise
The History of Timekeeping - 13/13
Time Zones
 In 1884, delegates from 25 countries divided the world into time
zones.
 The delegates divided the 360 degrees of the Earth into 24 zones
of 15 degrees each.
 In the United States, there are four time zones: Eastern, Central,
Mountain, and Pacific.

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historyTimekeeeping

  • 1. The History of Timekeeping Karen Isabelle Soares Karla Natalia Queiroz
  • 2. The History of Timekeeping - 2/13 Using the Sun noon sunset sunrise
  • 3. The History of Timekeeping - 3/13 Sundial Clocks  Oldest type of clock  Also called sun clocks  The shadow points to a number  Depend on the sun
  • 4. The History of Timekeeping - 4/13 Water Clocks  Around 4,000 B.C.  Babylon, Egypt, India or China  Water traveled through a tube  Tell time during the night
  • 5. The History of Timekeeping - 5/13 Dividing the Year into Months  12 Moon cycles in a year  Greeks divided the year in 12 months
  • 6. The History of Timekeeping - 6/13 Dividing the Year into Days  They divided the month in 30 days  360 Days in a year  360 Degrees in a circle 90° 180° 270° 360°
  • 7. The History of Timekeeping - 7/13 Dividing the Day into Hours  Egyptians and Babylonians  Sunrise to sunset in 12 hours, sunset to sunrise also in 12 hours  Whole day in 24 hours +
  • 8. The History of Timekeeping - 8/13 Minutes and Seconds  Sumerian Sexagenary Sistem
  • 9. The History of Timekeeping - 9/13 Mechanical Clocks  Invented in medieval Europe  Common in churches and monasteries  “Clock” is from the Latin word “clocca”  One time-keeping hand
  • 10. The History of Timekeeping - 10/13 Spring-powered Clocks  Around 1500  Became very popular among the rich  Was the precursor to accurate timekeeping
  • 11. The History of Timekeeping - 11/13 Pendulum Clocks  Developed by Christian Huygens around 1656  Pendulum clock had a minute hand  Used to swing a lot (about 50 degrees)  They stopped running after a while and had to be restarted
  • 12. The History of Timekeeping - 12/13 Quartz Crystal Clocks  Based on an electric property of the quartz crystal  When you apply voltage, or electricity, and pressure, the quartz crystal vibrates or oscillates at a very constant frequency.  Very precise
  • 13. The History of Timekeeping - 13/13 Time Zones  In 1884, delegates from 25 countries divided the world into time zones.  The delegates divided the 360 degrees of the Earth into 24 zones of 15 degrees each.  In the United States, there are four time zones: Eastern, Central, Mountain, and Pacific.