Have you ever wondered why in a single day there are 24 hours, and within one minute, 60 seconds? Here are the answers.
Number system is the most widely used by humans today is the decimal system, namely a base 10 number system. However, to measure time we use duodesimal system (base 12) and sexadesimal (base 60). This is because the method to divide the day derived from the number system used by the ancient Mediterranean civilizations.
In about 1500 BC, ancient Egyptians used 12-based number system, and they developed a system sundial shaped like the letter T is placed on the ground and divide their time between sunrise and sunset into 12 parts. While historians argue, the ancient Egyptians using number system based on the number of cycles will be based 12 months in a year or can also be based will be the large number of human finger joints (3 in each finger, excluding the thumb) that lets them count to 12 using the thumb .
Sundials next generation already represents more or less what we now call the "clock". While the division of the night into 12 parts, based on the observations of ancient Egyptian astronomers will be the 12 stars in the sky at night. By dividing one day and one night into each 12 hours, then by indirectly introduced the concept of 24 hours. However, the long days and long nights are not the same, depending on the season (eg summer days longer than nights). Therefore, the distribution of hours in a day varies according to season. Time system is called a system of seasonal time. In about the year 147-127 BC, a Greek astronomer named Hipparchus suggested that the number of hours in the day made it still as many as 24 hours, called equinoctial time systems. But the new system is now widely accepted by the discovery of mechanical clocks in Europe in the 14th century.
Eratosthenes (276-194 BC), a Greek astronomer other divide a circle into 60 parts to create a system of geographic latitude. This technique is based on 60-based systems used by the Babylonians who settled in Mesopotamia, which if traced further derived from the system used by the civilization of Sumer around 2000 BC. It is not known with certainty why use a number system based on 60, but the alleged saying for ease of computation because number 60 is the smallest number that can be divided up by 10, 12, 15, 20 and 30.
A century later, Hipparchus introduced a system of longitude 360 degrees. And in about 130 AD, Claudius Ptolemy divides each degree into 60 parts. The first part is called the minutae primae partes which means the first minute, the second part is called partes minutae secundae or second minute, and so on. Although there are 60 sections, which used only the first two parts alone where the first part of a minute, and the second to second. While the remaining 58 forming part of another unit of time smaller than the second.
This time the system takes centuries to widespread use. Even at the first timepiece that displays the minutes made the first time in the 16th century. This time the system used today by our modern human.
Sources: http://kolom-inspirasi.blogspot.com/2012/01/sejarah-sistem-waktu-dunia-kita.html # ixzz1k126eoLS
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