Tuesday, August 24, 2010

Experiment #1: Absorbant Properties of Various Soil Substrates by Gwenyth Allison

We wanted to know how much water can diferent kinds of soils hould.   My hypothesis was that the sand was going to loose and silt woud win.

To set up the experiment you need scissors, 2 pens, 3 dixie cups, a paper towel, a big measuring cup, a little measuring cup (1/4 cup), water, sand, dirt, and silt.  Use one of the pens and one dixie cup and the paper towel.  Then put the cup on a paper towel and, with a pen, draw a circle on the paper towel around the cup.  Do that three times.  Then with the other pen, poke three holes in the bottom of each dixie cup.  Then, with the scissors, cut out the three circles you made on the paper towel.  Put one circle in each paper cup.
Cutting paper towel
Choose one of the soils (sand, silt, or dirt), and put 1/4 cup into one of the dixie cups.  Put a different kind of soil (1/4 cup) in another dixie cup.  Then put 1/4 cup of the last soil-type in the last cup.

Then put 1/4 cup of water in each dixie cup.  Make sure you have the same amount of soil in each dixie cup and the same amount of water in each cup.  With three bowls, put a dixie cup in each of the bowls.  Then wait for about a minute.  Soon water will start coming out of the bottom of  the dixie cup.  Then carefully, without squeezing, pick up the dixie cup and shake it a little so you know it is done.  If its not done, put it back in and try another cup.

When they're all done, go back into the kitchen and get a teaspoon and pour one of the bowls of water into the teaspoon.  Write down how many teaspoons of water came out.  Do the same for all three.

My hypothesis was that the silt was going to soak up the most water, and the sand was going to soak up the least.  We measured how much water came out.


We discovered that silt soaked up the most water, but the other part of my hypothesis was wrong.  Sand did not soak up more water than dirt.  So half of my hypothesis was right!

Try this experiment at home and see what your hypothesis is!  If it is right, hooray for you!


  1. Sweet, so dirt didn't hold as much water. I wonder if the dirt already had some water in it, or if they were all the same dryness. I wonder how you'd test that. . .

  2. We sure like seeing your experiment. Where did the dirt come from? Where did the silt come from? How is the silt different from the dirt and sand?

    We hope you will keep blogging about your school work!