Anatomy videos for medical students

Sundials are early inventions of human beings for time purposes. The length of the shadow of the stone called obelisk and shadow clock determines the time of the day. According to history, the earliest sundials were invented by the Egyptians and Babylonians. Egypt happens to be located in Northern Hemisphere. What is the relevance of this?

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The sundial is the basis for the creation of the clock; hence, we have the terms clockwise and counter-clockwise. Clockwise is the movement of the hour, minute and second hands from left to right in circular motion while counter-clockwise is the movement of the hour, minute and second hands from right to left in circular motion.

The hands of the clock rotate clockwise because sundial, which is the forerunner of the clock, was invented in the Northern Hemisphere. If sundials were invented in Australia or anywhere in the Southern Hemisphere, the clock’s hands movement should have been counter-clockwise or anti-clockwise.