Sundials and Shadow Clocks
Despite Herodotus's attribution of the invention of the sundial to the Babylonians in 430 BC, the earliest known sundials were simple gnomons of Egyptian origin invented around 3500 BC. More complex devices were developed over time, the earliest surviving one a shadow clock made of green schist dating back to approximately 800 BC. Shadow clocks were modified sundials that allowed for greater precision in determining the time of day, and were first used around 1500 BC. Their major innovation was a modified, more precise gnomon that allowed for the division of night time into 50 parts, with an additional two "twilight hours" in the morning and evening. The shadow clock gnomon was made up of a long stem divided into six parts, as well as an elevated crossbar that cast a shadow over the marks. This early clock was positioned eastward in the morning, while at noonit was rotated to face west to measure shadows cast by the setting sun. The concept of measured shadows were adapted into larger, more public designs in the form of obelisks. Markers around the obelisk would indicate units of time, including morning and afternoon as well as the summer and winter solstices for ceremonial purposes.
Read more about this topic: History Of Timekeeping Devices In Egypt
Famous quotes containing the words shadow and/or clocks:
“It is the same for all men. None of us can escape this shadow of the father, even if that shadow fills us with fear, even if it has no name or face. To be worthy of that man, to prove something to that man, to exorcise the memory of that man from every corner of our life—however it affects us, the shadow of that man cannot be denied.”
—Kent Nerburn (20th century)
“Weighing the steadfastness and state
Of some mean things which here below reside,
Where birds like watchful clocks the noiseless date
And intercourse of times divide,”
—Henry Vaughan (1622–1695)