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Old December 9th 17, 03:53 PM posted to sci.astro.amateur
Mikko
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Posts: 15
Default The Equation of Time(keeping)

In article ,
"Chris.B" wrote:

Accurate clocks have been running to sidereal time for far longer than you
seem to realise.


Have you got any evidence?

The accuracy of the best clocks before pendulum clocks was abut 15
minutes per day. Before about 1650 the best pendulum clocks'
accuracy was about 10 seconds per day. In order to determine the
equation of time with a clock even one second per day, achieved by
Harrison in about 1760, is very little. Only in 1870 was accuracy of
0.1 seconds per day achieved, and equation of time determined with
a clock.

Mikko