"A world without time measurement?" This is a question that the following presentation aims to tackle by discussing Ancient Egyptian's invention of time keeping and their impact on modern time chronometry. A detailed timeline of the invention of calendars and clocks is also highlighted.

1. Ancient Egyptians as Pioneers of
TIME
KEEPINGand influencers of modern day
calendars

2. INDEX
Did You Know?
History of Chronometry in Ancient Egypt
The Time-Keepers
Evolution of the Calendar
How Ancient Egyptians Affected Modern Time
A World without Time Keeping?!
Clocks and Calendars Then and Now

3. If all of the world´s cultural heritage
was contained in a time capsule,
what would you include to
demonstrate the legacy of your
country?

4. Can you imagine our world without a
true understanding of "time"?

5. They were the first to
develop devices of
time keeping
We owe the division of
our day into hours and
minutes predominantly to
Ancient Egyptians
DID YOU KNOW?
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6. H I S T O R Y O F C H R O N O M E T R Y
I N A N C I E N T E G Y P T
Calendar
Clocks
To measure when the Nile flooding, which
threatened the entire country, took place, Ancient
Egyptians invented ways to "keep" time.
Since their agricultural system depended on time
keeping, a calendar would help them to determine
the flooding of the Nile, which was essential for their
farming practices.
Egyptians invented different types of clocks in order
to measure time. They used two main types of clocks;
the shadow clock and the water clock
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7. THE TIME KEEPERS
The Egyptians measured time during the day
using shadow clocks, predecessor to the more
recognizable sun dials seen today.
Obelisks were used as sun clocks by noting
how its shadow moved around its surface
throughout the day. From the use of obelisks
they identified the longest and shortest days
of the year.
Water clocks were different from shadow clocks in
that they could measure time during both day and
night. They had several functions: Determined
appropriate religious rituals, measured length of
speeches in courts and were displayed for general
public. The clocks functioned as follows: water was
poured into the basin, which had markings along the
inside that indicated hours. As the water level
decreased, the indicators inside the water clock
determined how much time had passed.
Shadow Clocks
Water Clocks
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8. EVOLUTION OF THE
CALENDAR
Lunar Civil
The Lunar calendar is based on 12 months,
each of which began on the first day in
which the old moon crescent was no longer
visible in the East at dawn. At first these
months were simply numbered within their
appropriate season, four months per season.
Each lunar month consisted of 29 days, so a
12-month year was 354 days long. However,
the heliacal rising of Sirius (the brightest
star visible from Earth) is an event that
happens every 365 days. So the rising of
Sirius would occur about 11 days later in the
final month of every year. Hence a
13th month was added to balance this
inconsistency.
As requested by the public, a simpler calendar
was introduced: The Civil Calendar
This calendar consisted of 12 months of 30 days
each, plus 5 additional days, which were added
randomly to make a year of 365 days and were
mostly special holidays and birthdays of the
gods.
Additionally, this calendar did not require the
sighting of Sirius, which made it go out of
sync with astronomical events. So, in 1460 years
the calendar slipped through a whole year,
causing a huge difference between the lunar and
civil calendar. Whereas, according to one
calendar, it could be harvest time, to the other
the floodwaters were just receding.
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9. H O W D I D
A N C I E N T
E G Y P T I A N S
A F F E C T
M O D E R N
T I M E ?

10. Accurate Timekeeping - Mechanical Clocks: Ancient Egyptian clocks
satisfied their purpose of time keeping, given that the majority of the
population did not care about time measurement accuracy as long as they had
a general sense of the day and the seasons. However, accuracy in time
keeping became increasingly important for business people, sailors and
churches. In 1283, the first mechanical clock was installed in England but had
its shortcomings. The mechanical clock's problem was later resolved in 1656
when 'Christian Huygens' (Dutch scientist) made the Pendulum clock. However,
its invention goes as far back as 1582 and is credited to Galileo Galilei
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The Gregorian Calendar: Having realized that the
Egyptian civil calendar required a sixth extra day
every four years, Julius Caesar reformed the Roman
Calendar and added a 29th day every four years,
introducing the Julian Calendar in 46 BC. However,
this calendar did not account for the 11 minute time
difference between the solar year and the 365.25
day year, which is when in 1582, Pope Gregory XIII
introduced the "Gregorian Calendar", which is the
most widely used calendar to date.
Industrial Revolution: Without accurate, globalized time, commerce and
travel could have faced some serious issues and the industrial revolution
may not have taken place.

11. A W O R L D W I T H O U T T I M E
K E E P I N G ? !
NO..
Calendars
Timepieces/Brands
Agendas/Schedules
Historical Monuments
Time Zones
Reminders
Meetings
Alarms
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12. C L O C K S A N D C A L E N D A R S
T H E N A N D N O W
S u n C l o c k
1 4 0 0 B . C
W a t e r
C l o c k
1 3 0 0 B . C
E l e c t r i c
C l o c k
1 8 9 5
A t o m i c
C l o c k
1 9 4 9
M e c h a n i c a l
C l o c k
1 2 8 3
P e n d u l u m
C l o c k
1 6 5 6
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13. C L O C K S A N D C A L E N D A R S
T H E N A N D N O W
L u n a r
C a l e n d a r
c . 3 0 0 0 B . C
C i v i l
C a l e n d a r
2 5 0 0 B . C
G r e g o r i a n
C a l e n d a r
1 5 8 2
A t o m i c
C l o c k
1 9 4 9
J u l i a n
C a l e n d a r
4 5 B . C
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14. CITATION
http://www.cs.xu.edu/math/math125/09m/08EBJ.pdfHistory of Chronometry in
Ancient Egypt
http://science.howstuffworks.com/innovation/inventions/5-amazing-ancient-
egyptian-inventions4.htm
http://www.egyptchronology.com/uploads/2/6/9/4/26943741/ch_3_investigati
ng_ancient_egyptian_calendars.pdf
http://www.touregypt.net/egypt-info/magazine-mag03012001-magf1.htm
https://www.scribd.com/doc/56781350/Ancient-Egyptian-Chronology-Edited-
by-Erik-Hornung-Rolf-Krauss-And-David-a-Warburton
http://www.time-for-time.com/clocks.htm
http://www.historyofwatch.com/clock-history/clock-timeline/
https://www.slideshare.net/bfrys/evolution-of-the-clock
https://www.scientificamerican.com/article/a-chronicle-of-timekeeping-2006-
02/

15. THANK YOU