How to Build a Water Clock

Water clocks, or clepsydras as they were known in ancient Greece, are one of the earliest types of clocks. They use the flow of water to tell the time. Just as modern clocks, clepsydras varied in function, size and design. Here are some steps you can follow to make a simple water clock at home.

Things You'll Need

• Two-litre plastic bottle
• Wax pencil
• Rubber stopper with one hole.
• Vinyl tubing
• Ring stand with a 4 inch diameter ring support attached
• 600ml beaker
• Food coloring
• Stop watch

Instructions

1. Cut the bottom off of your two-litre plastic bottle.

2. Draw a straight line using the wax pencil on the outside of the plastic bottle near the opening you just created. This is your fill line.

3. Remove the cap and replace it with your rubber stopper.

4. Insert the vinyl tubing into the hole in the rubber stopper. Clamp the tubing with the tubing clamp.

5. Place the plastic upside down in the ring support attached to the ring stand.

6. Place the other end of the rubber tubing inside the beaker.

7. Fill the plastic bottle with water to the fill line. Color it with food coloring.

8. Open the clamp just enough to allow a steady drip of water to flow into the beaker. Immediately start timing with the stop watch. Mark the level of water in the beaker every 10 minutes.

9. Poor the water from the beaker back into the plastic container and repeat the drip process marking every five minutes.

Tips & Warnings

• Use a right angle clamp attached to the opening at the bottom of the plastic bottle for added support if necessary.

• The chemistry items listed can be found in local hobby shops or online.