The history of timekeeping devices dates back to when ancient civilisations first observed astronomical bodies as they wandered across the sky. The astronomical bodies which ancient civilisations used to ‘tell the time’ were often the Sun and the Moon. Without these astronomical bodies to light their path and guide their way, people would have been completely lost.
The oldest description of a clepsydra water clock is from the tomb inscription of an Egyptian court official named Amenemhet. It is assumed that the object described on the inscription is a bowl with markings to indicate the time. The oldest surviving water clock was found in the tomb of pharaoh Amenhotep III (c. 1417–1379 BCE).
The Nakshatra System
When the first humans gazed up at the night sky, they saw patterns in the way that the stars were groups together. They named these groups after symbols which were dominant in their own environment. Over time, there emerged many ways with which to interpret the night sky.
Jyotisha, the system which influenced the Chinese and Arab systems of timekeeping, is considered the oldest system of timekeeping. It is the sidereal month which forms that basis of the Vedic lunar calendar. The sidereal month is the time needed for the Moon to return to the same place against the backdrop of the stars. This equates to 27.321661 days (i.e., 27 days 7 hours 43 minutes 12 seconds).
The resulting 27 sections are known as the nakshatras. Naksha means map and tra means vehicle. Each nakshatra is associated with a particular star: which is usually the brightest within the constellation. As this is a lunar timekeeping mechanism, the moon is of primary importance. The 27 nakshatras are further divided into three subgroups of nine.
The very concept of a lunar calendar forces and pushes us to consider a timekeeping mechanism which is not entirely governed by the force of the Sun. Perhaps the Moon, with its wispy white light, is imploring us to consider the vastness of the universe in which all of us presently reside.