Water clocks: How they emerged and evolved with time
Today, if someone asks you what time is it, you have multiple sources to refer to, starting from your smartphone to your wrist watch or just a good old wall clock. But this wasn’t always the case. Ever wondered how people measured time before all these modern-day accessories were invented? You are probably thinking sundials. Well, they were definitely an option, but with some real-world problems. As you know, for a sundial to work, there needs to be a fair amount of sunlight. So, in case it’s a cloudy day or night time, measuring time would be difficult. Okay, so how did our ancestors figure out time at night or on rainy days? The answer is water clock.
Water clocks: Not your regular tick-tock clocks
While the clocks we are accustomed with go tick-tock-tick-tock, water clocks sound like the flow of water, that is, drip-drip-drip-drip. But what are they like? Before we delve into that, let us tell you tell you the unique name by which water clocks are known as, clepsydras. Fascinating, isn’t it?
Water clocks rely on flowing water to measure the hours, minutes and seconds in a day. Okay, but how did they come into being? Well, some believe that ancient Egyptians came up with the idea in 14th century B.C., while others consider Babylonians as the earliest known inventors. Some scholars also suggest that water clocks emerged in China in 4000 B.C.
The ancient Greeks and Romans built these time-measuring devices using gears, that were also dependent on water pressure. Not only that, they improved the clocks by adding bells that made sounds at assigned hours. Interestingly, Romans especially used these clepsydras to set time limits in courts of law. If the water ran out, so did the defendant’s time. The ancient Chinese went ahead and had built a water clock tower as early as 1088 B.C. which was around 30 feet tall.
Inflow and outflow water clocks
These water clocks were there in two kinds: Inflow and outflow. Let’s take a quick look at them. Both inflow and outflow water clocks involved two big containers. The trick was simple, to fill one container with water and suspend it over the second container, and let the water drip through a tiny aperture at the bottom of the filled container to the other container.
Now, in case of inflow water clocks, the second container placed at the bottom was marked with hours of the day. Guess how people measured time? Simply by looking how full the container was at each point in time. And in case of the outflow water clocks, the technique was exactly the opposite, meaning, the hours were marked on the top container and people determined time by looking at how much water was drained away from the container.
Do water clocks exist today?
Yes, they do! In fact, Australia’s Hornsby Water Clock is a popular tourist attraction. Although it can still be used to measure time, the water clock is now exhibited as more of a kinetic art. The Time Flow Clock in USA’s Indianapolis Children’s Museum is another fine example.