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Timeline of time measurement technology
Timeline
of
time
measurement
technology
270 BC
-
Ctesibius
builds a popular
water clock
46 BC
-
Julius Caesar
and
Sosigenes
develop a solar calendar with leap years
1000s
- Sets of
hourglasses
were maintained by ship's pages to mark the progress of a ship during its voyage
1000s
- Large town clocks were used in
Europe
to display local time, maintained by hand
1335
- First known mechanical clock, in
Milan
1502
- Peter Henlein builds the first pocketwatch
1582
-
Pope Gregory XIII
,
Aloysius Lilius
, and
Christopher Clavius
introduce a
Gregorian calendar
with an improved
leap year
system
1656
-
Christian Huygens
builds the first accurate
pendulum clock
1676
- Motion works and minute hand introduced by Daniel Quare
1680
- Second hand introduced
1737
-
John Harrison
presents the first stable nautical
chronometer
, thereby allowing for precise
longitude
determination while at sea
1884
-
International Meridian Conference
adopts
Greenwich Mean Time
for consistency with
Nevil Maskelyne
's
18th century
observations for the Method of Lunar Distances
1928
- Joseph Horton and Warren Morrison build the first
quartz crystal oscillator clock
1946
-
Felix Bloch
and
Edward Purcell
develop
nuclear magnetic resonance
1949
- Harold Lyons develops an
atomic clock
based on the quantum mechanical vibrations of the ammonia molecule
2008
- Launch date for the
Primary Atomic Reference Clock in Space
.
See also:
clock