But how did people decide how long an hour, a minute, and a second are? The first people to break up a day into smaller parts were the ancient Egyptians.
More than years ago, they began using sundials, which were the first types of clocks. Have you ever noticed how your shadow grows bigger or smaller depending on what time of day it is? The Egyptians told time by putting stakes in the ground and measuring the shadows they made.
Eventually sundials got bigger and fancier. Ten is easy to count—you have 10 fingers and 10 toes—but 10 can only be divided by two and five. In fact, the hour was not commonly understood to be the duration of 60 minutes. It was not practical for the general public to consider minutes until the first mechanical clocks that displayed minutes appeared near the end of the 16th century. I read several years ago although I cannot now remember where that the number base 60 was is? The twelve knuckles or more simply the twelve finger bones do not include the thumb; fingers only.
I don't know how this system might be used to perform calculations like multiplication or division. Perhaps it is used simply to count items, literally, by the handful.
Counting to twelve can be easily achieved on just one hand by using the thumb and the twelve finger bones. Is that an ancient Babylonian word or at least Arabic? It is commonly claimed to derive ultimately from the Latin duodecim corrupted into the old French word, douzaine. However, and this is pure conjecture on my part, there are Arabic words in English which contain letter 'z' eg azimuth, azure, gauze, gazelle The reason a clock uses 12 hours is actually simple: use a forked stick in the sand to make a circle.
You can easily demonstrate the same effect by using 7 coins of the same size, 6 coins fit exactly around the 7th in the middle. Same with 4 parts, since there is no way of knowing without drawing a lot more circles if your 2 lines making the division are perpendicular. And division in 7 Parts is nearly impossible to do. Sign up to join this community. The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams?
Learn more. When and on what basis was it decided that an hour have 60 minutes and a minute have 60 seconds? Ask Question. Asked 7 years ago. Active 8 months ago. Viewed 3k times. Improve this question. Amit Tyagi Amit Tyagi 1, 12 12 silver badges 22 22 bronze badges.
Add a comment. Active Oldest Votes. From this site: The Babylonians about B. It says that nobody really cared about seconds until after the Middle Ages: Even the first clocks can measure periods less than an hour, but soon striking the quarter-hours seems insufficient. It also mentions the Babylonians: The Babylonians made astronomical calculations in the sexagesimal base 60 system they inherited from the Sumerians, who developed it around B. The Islamic-Arabian empires inherited many Roman and later Indian ideas starting with the Rashidun Caliphate in the seventh century.
Muslims scholars, after expanding on this knowledge greatly, reintroduced it to Europe in the eighth century through the Iberian Peninsula, which was then part of the Umayyad Caliphate. Medieval astronomers were first to apply sexigesimal values to time. Full moons were tabulated using these same divisions by Christian scholar Roger Bacon in the 13th century. Minutes and seconds, however, were not used for everyday timekeeping for several centuries.
Mechanical clocks first appeared in Europe during the late 14th century, but with only one hand, following the design of sundials and water clocks. Minutes and seconds were but hypothetical quantities of time.
According to David S. While sextants and quadrants no telescopes yet had long been used to quantify the heavens, due to the movements of the sky their accuracy was limited to how well a user knew the time. Tycho Brahe was one such pioneer of using minutes and seconds, and was able to make measurements of unprecedented accuracy. Many of his measurements required him to know the time to within 8 seconds.
Seventy years later, Isaac Newton used these laws to develop his theory of gravitation; showing that terrestrial and celestial motions were governed by the same mathematical laws.
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