Title. I saw a video showing it happening, but I don’t understand why.
In: 51
Take out a dry kitchen towel, preferably the sponge kind. Pour water on it. You see that the water jusr flows off.
Now soak it and wring it dry. Then pour water on it again and it soaks in nicely.
The mechanism is same in both earth and the towel. When they get really dry the material collapses, becomes compact and dense. Add moisture and they are nice and loose.
Why is this? Because water doesn’t actually go in to the earth or the towel, but between the fibres or particulates that make it up. If the material is really dry, the gaps are not big enough for water to fit in to it.
As you might have noticed, the wet towel, wet sponge, or just wet dirt weighs more and takes up more space. This is because there is actually more stuff in it, water, and this expands the material like little wedges pushing the parts of the material open, so much that water can soak into it.
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