See water “walk” in this incredible experiment! 

Photos: Yochanan Ghoori

You’ll see the colors from each cup travel up and down the paper towels, filling empty cups and mixing into new colors.

You will need:

7 clear plastic or glass cups

Water (about 7 cups)

Food coloring

(3 colors: red, yellow, and blue)

6 paper towels

Scissors, if necessary

How to do it:

1. Fold the paper towels in half the long way.
2. Press the folded paper towels tightly and then fold them in half (the long way) again. They should be folded in half twice now.
3. Now you’re going to fold it across the middle to make a “letter V” out of the paper towel. Set these 6 Vs aside for the moment.
4. Line up your cups, spaced about an inch or so apart.
5. Fill every other cup about halfway with water, adding a few drops of different-colored food coloring to three of the cups of water. You should have one empty, one full, one empty, one full, in this pattern:

Cup 1: Red water

Cup 2: Empty

Cup 3: Blue water

Cup 4: Empty

Cup 5: Yellow water

Cup 6: Empty

Cup 7: Red water

6. Turn your Vs upside down, putting each “leg” or side into a cup. If the leg seems too big, trim a bit off the bottom. Each cup should have half of one paper towel V in it and half of the next paper towel V in it. One half of each V will be in a cup with colored water and one half will be in an empty cup.
7. Watch the cups over several hours (and even leave them overnight, but don’t stay up!). You’ll see how the water “walked” up the paper towels and into the empty cups — and even formed some new colors in the process by walking up different paper towels and “mingling” in the process.

Voila! Walking rainbow water!