Capillary action

We have a new science experiment on our table. We’ve been monitoring it for several days now and enjoying the changing colors.

We started with four bowls of water and two empty bowls (gotta keep things evenly divisible by two when you have two kids :) ) Each kid got to chose two colors and put a few drops of food coloring into two bowls of water. Then the rolled up paper towels and made bridges between the cups of colored water and the empty cups.

in the beginning

The theory was that the water would wick up the paper towels and back down the other side, filling the empty bowls. Each empty bowl had two paper towel bridges coming in to it, so there would also be some coloring mixing as a beautiful side effect.

We watched it closely while we had afternoon snack. Within an hour or so the color was making good progress. For some reason we don’t understand the yellow wicked much faster than the other two colors.



By the end of dinner the yellows had started dripping into the empty bowls, and creeping up the dry end of the other paper towel bridges!


The next morning all of the colors had made it over their bridges and were dripping into the middle bowls, creating lovely shades of orange and green.

12hrs p1

12hrs p2

12hrs p3

Lex filled each of the water bowls up evenly, but somewhere along the way between the sink and the table some water spilled out of one of them (the yellow bowl across from the blue). As the water levels tried to level out, some of the green water started working it’s way up the yellow bridge!

Saturday evening, about 24hrs after we started the project, it looked like this.


This afternoon, nearing 48hrs since we started the experiment, the green hasn’t yet made it to the yellow. The wicking action is slowing down. I wonder if the paper towels get saturated? I’m just guessing at the science behind all of this because I’m too lazy to look it up (ok, I did a quick Wikipedia search for the basics). Maybe we’ll leave it for another day or so. Eventually things have to get cleaned up around here.



For now I’m just enjoying the beautiful experiment/table decoration. Especially considering the rest of my table decorations consist of two candles we haven’t used in ages, two vases of dead flowers (which will be freshed up at our trip to the farm tomorrow) and an empty yogurt cup with a dead flower and a (likely also dead) little worm Eve brought home yesterday.

Hooray for colorful science!

2 thoughts on “Capillary action

  1. I just noticed that the reason the green stopped moving over the bridge is because the water levels are even between the yellow, green, and blue bowls. Balance has been achieved!

  2. WHAT A LOVELY POST until the last paragraph about dead worms and flowers, haha I LOVE YOU! i wouldnt want it any other way. i love the thought of your house, such warm hearts and curious brains. i cant wait to see you guys. the questions im still curious about is why the yellow traveled faster-

    lots of love!

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