Why 60 Minutes in an Hour?
You might have surprised many times, why there are 24 hours in a day and 60 minutes in an hour. The 24-hour day concept comes from the ancient Egyptians. They divided the day into 10 hours with devices like shadow clocks and then added one hour at each end (one for twilight and one at the end of the day) same 12 hours of the night.
60 minutes concept comes from Mesopotamia civilization made astronomical calculations in the sexagesimal (base 60) system which developed it around 2000 B.C.
Later Claudius Ptolemy a greek astronomer explained and subdivided each of the 360 degrees of latitude and longitude into smaller segments by influencing from the sumerian hexadecimal base. He divided Each degree into 60 parts called minute and each minute again subdivided into 60 smaller parts called seconds.
The first mechanical clocks that displayed 60 minutes appeared near the end of the 16th century and later clocks seconds were introduced.
Biggest Clock in the World
The Sundial clock in Jantar Mantar is the world’s largest stone sundial situated in Jaipur India and was constructed in the 17th century. In this giant clock, even 2 seconds time difference can be seen by naked eyes. The ramp of this Sundial points directly towards the North Pole. There is a curved scale on both sides of the ramp, which has markings.
From the position of the shadow of the ramp on the scale, you can accurately read the local time of Jaipur. The long sectional marking in this image indicates HOURS. Each Hour is further divided into intervals of 15 minutes which further break up into five minutes to one minute and lastly, each minute is divided into thirds. Therefore, the accuracy of this sundial is 1/3 of a minute or 20 seconds.
Oldest Sundial Ever Discovered
A sundial discovered outside a tomb in Egypt’s Valley of the Kings may be the world’s oldest ancient Egyptian sundial. The sundial was found on the floor of a workman’s hut, in the Valley of the Kings, dated circa 1550 B.C
The significance of this piece is that it is roughly one thousand years older than what was generally accepted as the time when this type of time measuring device was used, Past sundial discoveries date to the Greco-Roman period, which lasted from about 332 B.C. to A.D. 395.
The sundial is made of a flattened piece of limestone, called an ostracon, with a black semicircle divided into 12 sections drawn on top. Small dots in the middle of each of the 12 sections, which are about 15 degrees apart, likely served to give more precise times.
Device for Nightkeeping, Merkhet
Do you know how in ancient Egypt people were measuring time at night? Ancient Egyptians used the device called The merkhet. Merkhet involved the use of a bar with a plumb line, attached to a wooden handle. it was more efficient than other contemporary devices, such as sundials, which were rendered useless during the dark.
The Merkhet was used to mark where a particular star would sink below the horizon and then reappear later. For the operation to work, two Merkhets were required, one aligned with Polaris, the North Pole star.
One person would have stood at an observation point and sighted the falling (or rising) star through a narrow slit in a palm leaf, known as a Bay. A second person could move until a Plum Bob suspended from a Merkhet crossed the line of sight and then mark a point on the ground. This process would be repeated to create an angle between where a star rises and where it falls.
Oldest Alarm Clock
Do you know who invented the first-ever alarm clock? The first known alarm clock can actually be traced to Ancient Greece and was invented by Plato, a famous philosopher whose ideas are still studied today. This alarm clock was an extension of an ancient water clock.
The upper ceramic vessel supplies the next vessel through an outflow funnel which was appropriately calculated for a predefined time.
When the second vessel becomes full at the programmed moment (for example after 7 hours) through the internally located axial pipette, it evacuates fast towards the next closed vessel and forces the contained air to come out whistling through a tube at its top.
After its function, the third vessel empties slowly (through a small hole located at its bottom) towards the lower storage vessel in order to be reused.