On Friday, December 8, 2017 at 4:30:33 PM UTC, Mikko wrote:
In article ,
Gerald Kelleher wrote:

For those who want to understand history it is important to know that a clock
is a device with one job - to maintain a constant or average pace.

You then ask what is the constant pace and how is it derived using the Sun
crossing the meridian each day/night cycle while knowing that each cycle is
different.

No, I don't. Instead I ask whether and how well the clock will do what
it is made to do.

Nearly impossible to find men of stature who have enough engineering sense along with basic astronomical principles to discern clocks are essentially constructed on the 24 hour cycle and equable hours, minutes and seconds are derivative of that core principle. The fact that a star returns to the foreground reference requiring two stick can't displace a meridian line which determines noon with sunrise and sunset representing a location exiting and entering the circle of illumination each day.

Clocks follow from the 24 hour day and not the other way around so learning how the timekeeping AM/PM cycle is created first becomes the key to understanding what is right from what isn't.





In order to understand history, the point is that until
recently clocks were not very accurate (nor common). Astronomers
who wanted to study the equation of the time could only compare the
(apparent) motions of Sun and fixed stars. Even that was not easy as
Sun and stars are not visible at the same time.

Mikko

You are like the brexiteers who make things up as they go along hence the actual structure of timekeeping and the role of the Equation of Time(keeping) would only really appeal to those who have a combined interest in the subtleties of clocks development in tandem with the subtleties of planetary motions.