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all the time in the world

The Mouse Ran Up The Clock

By Allan Eastman

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The Sands of Time

Sundial on the sand with a white feather

The concept of the sundial stems back to early times in human history when people measured local solar time.


Early civilizations sought ways to measure smaller packets of Time as well. Someone in ancient Babylon noticed that as the Sun moves across the sky, its shadow moves through a defined arc. The next step was to build a Tool with markings to measure the movement of the shadow, creating a Sundial which records the passage of Time throughout a (sunny) day.

Sundials spread throughout the antique world and became highly developed in Pharaonic Egypt. They ranged from huge obelisks to a small hand held sundial which must hold the record for being the first example of a personal pocket watch. The Egyptians had already adopted the zodiacal system of the 24 hour day and generally divided their sundial’s calibration into the 12 daylight hours.


Sundials measure Local Solar Time and hence are subject to major inaccuracies because the Earth follows an elliptical, not a circular, orbit around the Sun. They are also affected by the changing tilt of the planet on its axis. Depending on the time of year, Sundials can be up to 17 minutes out of line with modern more accurate Time standards.

Still, the Time provided by Sundials worked for the Egyptians for one simple reason – this Tool gave everybody in the same place a common Time reference that was accurate for everyone in the immediate vicinity. Social and religious functions could now operate on a common schedule.

Presumably, this is the point when people started being late for meetings.

In parallel with Sundials, the Ancient World also developed other Timekeeping Tools like the Sand Clock and the Water Clock. The first worked by having a certain amount of sand run through an opening that was measurable to a certain period, probably originally calibrated to a sundial. Sand Clocks later developed into the so called Hour Glasses which were regularly used in western cultures for about 2000 years. The sailors of the British Navy at the height of its Empire in the early 19th Century kept their Ship’s Watch with an hourglass. As the sand ran out, a bell was tolled the requisite number of times to mark the Hour and the glass turned over to begin the process again. A sailor that missed the turn of the glass when the last grain of sand ran out was subject to a savage flogging.

Water Clocks work on the same principle with water dripping through a small hole at a regular rate. The passage of Time was recorded through markings on the vessel either as the water emptied out of one container or filled another. A similar Tool was a Candle Clock which burned down past a series of calibrated markings.

These devices all had severe accuracy problems as well. Water evaporates and freezes, candles change their rate of burn in drafts and sand running through an opening eventually grinds out a larger opening. Still, they were key Tools in an increasing Human preoccupation with Timekeeping.

Rome used all these systems but especially sundials which were widely distributed in both civic and private life. The Romans also began to split the hour into smaller and smaller units with some of the civil sundials measuring both half and quarter hours. So already 2000 years ago, people were beginning to complain about the so called “Tyranny of Time” with the need to adhere to a tighter and tighter daily schedule.

These particular Tools stayed in use for two millennia and more but finally, were all plagued by problems of inaccuracy. The search for the perfect Time Tool continued.

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