A  Science and Technology Odyssey in Cyberspace-Time 
20000 BC to 1800 AD
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Time Period

Title Page

20000BC-301BC

300BC-1499AD

1500 - 1699

1700 - 1800

 

 


Back to Timeline 20000 B.C. thru 301 B.C.

Sundials

Ancient Sundial

"Sundials were one the earliest forms of telling time. One of the first ancient people to use sundials were the Sumerians." from A HISTORY OF CLOCKS.

 

 A HISTORY OF CLOCKS

 

"The inventions of the hemispherium and the hemicyclium are attributed to Berosus (356-323 BCE), a Chaldean priest and astronomer who brought these types of sundials to Greece. Both dials use the shape of a concave hemisphere, a shape like the inside of a bowl that mimics, in reverse, the apparent dome shape of the sky." from ANCIENT INVENTIONS

 

 

Modern Digital Sundial

"The digital sundial displays the current time in the shape of digits. This is achieved by casting the sunlight through a set of masks onto a transparent screen. The device is purely passive - that is, there a no moving parts or electrical components. Inspired by Ian Stewart's article, "What in heaven is a digital sundial?" (Scientific American, 1991), this invention comprises the first physically realizable digital sundial." Quote from Digital Sundials?.

 

 

 

 

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