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Sundials and the Summer Solstice
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- เผยแพร่เมื่อ 17 ส.ค. 2024
- Join us for a unique program on sundials and mathematics from ancient times to today. In this presentation Jere Blackwelder travels through the centuries, exploring how civilizations have viewed and measured time. Sundials are the common element. This event was held on Tuesday June 25, 2024 at the Brookside Museum in Ballsont Spa, N Y.
Contents:
00:00 Welcome - William Allerdice
01:56 Stephen Williams introduces Jere Blackwelder
04:53 "Howdy!"
07:58 Sumarians and Base 60 Mathematics
10:20 Babylonians - Twelve Hours of Sunshine
11:36 Egyptians - the first sundial and a rudimentary Base 10 mathematics
14:00 Greeks - conquer the Egyptions and realize seasonal hours
18:38 The Dark Ages and how do you multiply Roman numerals?
20:25 The Persians - Arabic numbers and finding the zero
22:00 Copernicus Charts the Skies
26:00 Clock Time vs Sun Time
30:55 The advent of accurate clocks - Railroad time and Telegraph time
32:40 Charles F. Dowd, of Saratoga Springs proposes the use of time zones
34:38 Local Sundials
44:50 Questions and Answers