It seems that time passes in the same pattern, and that time is equal to all but the “Theory of Relativity” proves otherwise. “Time is a relative thing” according to Einstein, which came out with the theory of Relativity.
History of time: Records of time keeping are found 25,000 years ago, but of course, they weren’t as accurate as now a days. Man used nature to indicate time e.g. Full Moons. It is widely suggested today that time was kept in a “Calendar”‘ way. This means that they divided the time into big units and could only tell the time in specific occasions. e.g. a normal person, 20,000 years ago couldn’t tell his partner the time at any given period. He had to wait that the moon would go full, or the sun will dawn, or by looking at the stars, etc. They almost couldn’t describe when in the future, a thing is to happen. They would say something like “In 2 full moons and a high sun we’ll go hunting”. He couldn’t tell exactly in how many hours or minutes things will happen because as I said before Nature was his time keeper + The term “Seconds”, “‘Minutes, “Hours”, etc, didn’t exist back then.
A clock must have 2 basic components:
1. Power Source
2. A “Release Power” source.
The hand clock (watch) was invented by A French Company named Berege back at 1810. During the 1800’s a drastic advancement has occurred in mechanical clocks with the invention of the naval time keeper which is used up till today by sailors to find their position in an area.
During the 20th century, a general scientific advancement occurred which led to the invention of Quartz and atomic clocks which are very accurate.
Sun Clocks: Device used up till beginning of 19th century. During the day, when the sun shines, a stick is placed on a flat surface. The shadow it creates moves as the sun moves, allowing us to keep track of time. Evidence of sun clocks are found during the Ancient Egyptian era.
Cesium Clock: An Atomic Clock that its function is based on the difference of the energy of 2 Cesium atom’s nucleus in a magnetic field. The cesium clock is extremely accurate and the “Second” we know today (1/86400 of a day) was invented thanks to this time device.
Water Clock: Water clocks are known to have been used back in the Roman Empire. The function of the water clock is very simple. A water container, marked on its side is filled with water. A hole is made in the container. As water pours out, the water’s surface area drops and touches the different marks on the sides and by doing so indicating us how much time has passed. More complex water clocks were built by the Chinese during the 1100’s but they were very sophisticated.
Hand Clocks (watch): Hand clocks are the time devices I’ll write about in more detail.
Watches are small clocks which a person can carry with him to any place. Sort of a “‘Portable Watch”. The possibility of creating a watch began with the invention of the spring during the 1500’s. The first watches consisting on a spring were too big and could only be carried on one’s belt.
When the safety spring was invented in 1675 watches could be built in a much smaller size, and became very popular as a pocket clock. During the 19th century, great watch inventors made those pocket clocks very accurate.
The first hand clocks (worn on hand) were seen during WW1. These clocks were very useful to army men. During the two world wars, hand clocks became better, cheaper, & smaller. Many functions were added to them such as: anti shock, water resistant, “looming” time, etc..
Towards the beginning of the 70?s, Electronic watches were created. They consisted on certain Quartz properties, and were very accurate in compared to older non digital hand clocks.
The Digital watches were built during the 1970’s. Those clocks could be built very small in size, so many features were added to them such as: Stop watch, Light, Alarm, schedule, etc. These digital watches are commonly used today (so are the non – digital hand watches).
ConclusionAs mankind evolves, so does their knowledge of time. As their knowledge of time evolves, so do the devices which keep track of time. Today, clocks are “1000″ times better than the clocks of the Stone Age man. This demonstrates us how humanity has evolved since the stone age.