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Hey there! Squeaks and I are exploring the mysterious world of caves.
They can seem to be a little dark and spooky…
…but they’re also so amazing!
We recently visited our friend Sam the Bat in his family cave.
And even though Squeaks thought caves were dark and scary at first,
now that he’s started to learn more about them, he’s not so afraid.
Oh, but he still thinks that the rock icicles growing from
the roof and floor of the caves still look pretty creepy.
There’s a good reason they happen, though, and it’s not scary at all!
Do you remember when we talked about how important water is in forming caves?
Those weird looking rock structures that look like they’re growing
from the ceiling and floor of the cave are also because of water.
And they have some really fun names:
The ones on the ceiling are called stalactites…
…and the ones on the floor are called stalagmites!
Now, those words sound kind of the same,
so here’s a little trick that you can use to remember which is which.
The word stalaC-tites has the letter C in it…
and the word ceiling starts with the letter C
And stalactites are stuck tight to the ceiling…
While the word stalaG- mites has the letter G in it…
and the word ground starts with the letter G!
And stalagmites grow up from the ground.
Neat, right?
Of course, they don’t technically grow.
Rocks aren’t alive, so they don’t really grow the way plants and animals do.
They just get bigger over time.
And that’s thanks to water making its way through the cave!
Squeaks comments
Oh! Squeaks thinks rocks are too hard to be changed by water.
Which makes sense, because we can pour water on rock
and it looks pretty much the same… just wetter.
Well, land and rocks are changed by water…
it just happens so slowly that we can’t see it with our eyes.
But we can do an investigation to help show us how this happens!
Okay, for our investigation we just need a few things.
A glass of water… a spoon… and some sugar.
Let’s start by looking at our sugar.
What observations can we make? The sugar feels gritty, like sand.
And it’s kind of hard and crunchy.
Oh, and of course we know that sugar tastes sweet!
We just got the water out of the tap…
and we know water doesn’t have any taste.
And it looks clear.
Let’s see what happens when we put the sugar in the water and stir it a little.
Yes!
It looks like it disappears!
We can’t see little pieces of sugar in the water at all.
But… if we take a spoonful of the water and taste it…
mmmm it’s sweet.
Even though we can’t see the sugar, it’s there!
Our evidence is that we can taste it.
The water broke the grains of sugar down into
even smaller pieces and these got mixed into the water.
The sugar pieces are so small we can’t see them, but we sure can taste them!
But what if we want to see the sugar again?
Well, If we left the glass alone for a long long time…
we would see that the water dries up but the sugar stays.
We tried this experiment and, look, see?
The sugar is still there!
Squeaks wants to know what this has to do
with caves and stalactites and stalagmites!
Well when water makes a cave,
it breaks down rock into smaller and smaller pieces, just like the sugar.
These tiny pieces of rock get mixed into the water and we can’t see them anymore.
And if this water runs over a crack in the ceiling of the cave, it drips out…
carrying the little pieces of rock with it.
As the water dries up, it leaves the little pieces of rock behind…
just like when the water dried up in our investigation, it left the sugar behind.
If the water dries up before it drips to the ground, it forms a stalactite…
and if it drips onto the ground, a stalagmite grows up!
Over a long period of time…
more slowly than our eyes can see…the rock piles up.
It looks like a rock icicle that grows and grows and grows.
So what do you think?
Maybe they still look a little odd… but they’re definitely amazing!
Thanks for joining us here on SciShow Kids.
If you want to keep learning and having fun with Squeaks, me,
and all of our other friends, be sure to hit the subscribe button,
and we'll see you next time here at the Fort!
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