The shadow clock is one of the earliest ways of measuring time. It features a figure that is placed upright. When the sun shines on this clock, it casts a shadow of the figure. As the sun rises and sets in the sky, the light hits the clock in different ways. This makes the shadow appear at different angles. This tells what time of the day it is.
Ancient Egyptians used obelisks to measure time. These are a tall, narrow form of the shadow clock. The obelisk was then followed by the sundial. Both the obelisk and the sundial allowed the Egyptians to tell time.
Questions
“As the sun rises and sets in the sky, the light hits the clock in different ways.”
What inference does this detail support?
The shadow clock only works when it’s cloudy.
The shadow clock only works when the sun is visible.
Today, shadow clocks no longer work.
To tell the time at night, ancient Egyptians would light fires.