Time from Sticks and Shadows - Making a Sundial

This video shows how the apparent motion of the Sun across the sky affects the length of a shadow cast by a pole. This can be used as a simple timing device known as a sundial.

In modern times we can calibrate the sun dial with a clock as shown in the video, in ancient times you'd need something else. The noon position is when the shadow is the shortest, you could then use a large bucket of water or bag of sand as a timer. Collect the sand / water from noon on one day until noon on the next. Then divide the collected mass into 12 equal portions, these are 1 hour timers. You can then use each portion to mark the ground in hours as shown in the video.

The seasonal effect will alter the length of the shadows but not the positions it is possible to mark this on the ground too and that will allow you to tell the date as well as the time.

Original video filmed by Notice Something