Water Clock

Clepsydra

I chose to investigate telling time before iphones, watches, and gears were invented. In ancient time sundials were used to tell time, but the problem was it wasn’t always accurate and without the sun, the clock wouldn’t work. Therefore, the water clock was invented. The oldest known example is dated to 1500 BC, and is from the tomb of the Egyptian pharaoh Amenhotep I. It is called the clepsydra ("water thief" in Greek), in the 16th century B.C.E. A water clock is a device in which time is measured by the flow of water into or out of a vessel. Since the water clock depends only on the flow of water, it can operate at night or on days when the sun doesn't shine. The Greeks and Romans also came to depend on water clocks, and both cultures made improvements on the basic design.

For this experiment I took two Powerade bottles of the same size. I cleaned them out and took off the paper. I put hot glue on the top of one lid and glue the lids together. Once they dried, take a drill bit and make two holes through both lids big enough to fit the straws. Cut the straws to equal sizes. Place the straws so each side of the lid has a long piece. Add hot glue to the inside of the lid and around the straws so water can only go through the straw and not the hole. Add lids to one bottle. Add water to the other bottle and mark a fill line so it will always be the same. When ready attach the two bottles by the lids. Have timer ready to count each minute and mark the bottle at each one minute mark. Continue until the bottle of water empties completely.

Test one I used to Powerade bottles and the straws were from a lollipop (chubs). The water clock lasted 43 minutes. The difficulty occured because some of the minute lines were too close together. It was hard to mark. The second model of the water clock I used Gatorade bottles with straws from Wawa. They had a bigger opening. In testing the clock only lasted 2 minutes and 15 seconds. Therefore, I created a third water clock using a narrower water bottle and the first set of straws (chubs). This water clock was just right. The narrower bottle made the markings easier than the first, and it measured 43 minutes.

The first water bottle was wide, had a time of 43 minutes, but hard to mark minute to minute level. In the second water bottle, the straws were too wide so the water only measured 2 minutes and 15 seconds. However, the third bottle because it was narrower and had the small straws was just right. The markings were easy to mark every minute, and it lasted 43 minutes. After testing each bottle three times, the clocks proved to be accurate and consistent. I would improve this project by creating a 3D water clock like I wanted to in the beginning. I would also like to have different bottles all measuring the same amount of time by varying the straws’ openings.