In a scene from my third book, “Great Heats,” the ancient Mound Builders of Ohio erect a tall pole, simulating a large sundial, to give them a more accurate idea of the schedule seasons keep and to help the villagers better manage the planting and harvesting of crops while preparing for the harshness of the inevitable winter.
In researching ancient timekeeping – meaning shorter than a day – I found that the ancients of every civilization had attempted to get greater and greater accuracy, including when the sun wasn’t shining, by using clocks that burned incense, or water clocks, or hour glass designs using sand.
Improving on the search for accuracy, led to gearing and when tied to metals, in the 13th century allowed the
idea of oscillation or the repetitive beat, like that of a pendulum in this astronomical clock from the Exeter Cathedral in England.
Wound metal, or springs, could also produce oscillation so by the 17th century, with many choices for automation, clocks were getting fairly common and more accurate, even on carriages.
And, with more and better techniques for manipulating metal, the size of clocks became smaller (made by watchmakers, derived from clocks in “watch towers”), so that one 
Today, with the ever-increasing use of phones and tablet-sized computers as a timepiece, watches may disappear from usage, much as the pocket watch has today, but the need to know, with accuracy, what the time is at the moment, will assure the existence of clocks.
I once asked a psychic with whom I was working on a television production, what his thinking was about the universe. “Everything is a rhythm,” he said. “From the beating of your heart to the movement of stars and the passage of time. It is all a rhythm, which is why we respond to music or can become mesmerized by a ticking clock.”
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The tick of the clock reminds me that today is fading away, while tomorrow is inexorably on its way.
~~ Ronald D. Giles
