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I know right? That was so weird! I wonder if…
我知道对吧？非常奇怪，我在想是不是……
Oh, hi! Squeaks and I just got back from a nature walk! And we saw the strangest thing: a tree branch that looked like it was growing white hair!
哦，嗨，我和吱吱刚从大自然散步回来！我们看到了一些奇怪的东西：一根看上去像长了白发一样的树枝！
We took some pictures—see? It looks just like hair!
我们拍了照片，看，是不是像头发！
We decided we wanted to investigate it further, so we carefully took a branch back to The Fort.
我们决定要进一步调查它，所以我们小心翼翼地把一条树枝带回了城堡。
We were going to look at it under the microscope and maybe run some tests on it.
我们打算在显微镜下观察它，或许可以做一些测试。
But by the time we got back, the hair had turned into this liquid!
但等我们回来的时候，头发已经变成了这种液体！
Anyhow, we just asked The Fort's supercomputer to figure out what we found. And we were just waiting for the results...
不管怎样，我们刚刚让城堡的超级计算机看看我们发现的是什么。我们正在等结果……
Perfect timing! Aha! What we found was actually ice! And That's why it melted!
时间刚刚好！啊哈，我们发现的其实是冰，这就是它融化的原因！
Apparently, this kind of ice is super rare. It only appears when conditions are just right.
显然，这种冰非常罕见，只出现在条件合适的时候。
And it forms because of a special property of water: it's stickiness!
它的形成是因为水的一种特殊属性：粘性！
You're right, Squeaks—water doesn't feel as sticky to us as stuff like honey. But it really likes to stick to itself.
没错，吱吱。水不像蜂蜜那么黏，但它真的很喜欢自成一体。
If we could look at water really closely, we would see that it's made of tiny, identical pieces.
如果我们仔细观察水，会发现它是由一模一样的小碎片组成的。
And these pieces like to stick to each other — kind of like magnets!
这些碎片喜欢粘在一起，就像磁铁一样！
And we can actually see this. Watch what happens when I add drops of water to each other on top of this penny.
我们可以看一下。看看当我在硬币上滴上几滴水会发生什么。
See how the water makes a sort of bubble shape?
看看水是如何变成气泡的形状的？
The water is sticking to itself so strongly that it doesn't spill over the sides!
水紧紧地粘在一起，不会溢出来！
Scientists don't call this stickiness, though. When a liquid sticks to itself like this, they call it cohesion!
不过，科学家们不把这种现象称为粘性，当液体像这样粘在一起时，他们称之为“凝聚”！
If we try the same thing with another liquid, like rubbing alcohol… you can see it doesn't make that dome.
如果我们用另一种液体做同样的实验，比如外用酒精，你可以看到它不会形成圆顶。
That's because the alcohol doesn't have the same cohesion as water does.
那是因为酒精的内聚力不如水。
Ah, yes Squeaks! What does cohesion have to do with that icy hair we saw?
啊，是的吱吱！凝聚和我们看到的冰状头发有什么关系呢？
Well, it turns out cohesion is a big part of why the ice forms that way.
事实证明，凝聚是冰形成的一个重要原因。
You see, the tree branches the hair ice was growing on have water inside them.
你看，长着冰头发的树枝里面有水。
That's because, if you were to look inside a tree, you would find a bunch of little tubes that carry water and nutrients all around.
这是因为，如果你观察一棵树的内部，你会发现有一些小管子到处输送水和营养物质。
And some of these tubes connect to the outside of the tree, making little holes that you can see with a microscope.
其中一些管子和树的外部相连，形成小洞，用显微镜可以看到。
Now, when the branch breaks off the tree, these tubes can fill up with rainwater.
现在，当树枝从树上折断时，这些管道可以装满雨水。
when the air around the branches begins to get cold, the water at the very edges of these tiny holes starts to freeze.
当树枝周围的空气开始变冷时，这些小洞边缘的水就开始结冰。
And when water starts to freeze, it gets bigger— because all those tiny pieces of water arrange themselves into a special pattern called a crystal, and this pattern takes up way more space than regular, liquid water.
当水开始结冰时，它会变大，因为所有这些小块的水会排列成一种叫做晶体的特殊形状，这种形状比普通的液态水占据更多的空间。
And since the ice needs room, it moves to the outside of the branch.
因为冰需要空间，所以它移到了树枝的外面。
Knowing that, what do you think happens to the liquid water that's still in the tube as that frozen part grows?
知道了这一点，大家认为当冷冻部分变大时管道内的液态水会发生什么呢？
Let's think about it this way: We said that the pieces that make up water stick to each other.
咱们这样想：我们说过组成水的部分是相互粘在一起的。
What would happen if a group of friends were in a line holding hands next to a doorway...and the first friend went through the door?
如果一群朋友在门口手牵着手排队会发生什么呢？第一个朋友进门了吗？
Right! The first friend would pull on the next person in line so that they ended up next to the door!
没错！第一个朋友会拉着队伍里的下一个人朋友，这样他们就站在门边了！
Yes, good job, Squeaks! As the frozen water goes out into the air, the next bit of water gets pulled right up to the edge of the hole!
是的，吱吱，说得好！当冰冻的水进入空气时，下一滴水被拉到了洞的边缘!
And it gets pulled there because of cohesion. Then that water freezes and goes out of the hole.
它因为凝聚力被拉到那里。然后水结成冰，从洞里流出。
This keeps happening over and over again…. until there's a long, thin hair of ice!
这个过程一直重复……直到出来一根又长又细的冰毛！
And since they were just super thin ice strands, the when we brought it inside was more than enough to melt them.
因为它们只是非常薄的冰丝，当我们把它们带进去的时候就足够将它们融化了。
Ooo that's a good question! What do you think would happen if we took this water and put it outside? Would it become hairs again?
问得好。你觉得如果我们把水放在外面会发生什么？也会变成头发吗？
You're right. If we froze this water again, it would just make regular ice, not hair ice since it's not in that branch anymore, so it doesn't have those holes to grow out of.
没错，如果我们再次冻结这些水，它就会变成普通的冰，而不是头发冰，因为它没有在树枝上，所以就没有那些洞可以长出来了。
Oooo look at this, Squeaks! Thanks to cohesion, ice can grow into some other pretty spectacular shapes.
哦，吱吱，看看这个！由于凝聚的作用，冰可以变成其他一些非常壮观的形状。
If water freezes in holes in dirt much in the same way it does in branches that grow hair ice, you can get ice needles.
如果水在泥洞里结冰，它就像在树枝上形成冰头发一样变成冰针。
And if it happens through long thin cracks in plant stems, you get frost flowers!
如果水在植物茎的细长裂缝里结冰，它就会变成霜花！
We were really lucky to see this today, Squeaks!
吱吱，我们今天能看到这个真的很幸运！
That's a great idea—I bet Mister Brown would love to see our pictures. Let's go show them to him!
是一个好主意，我敢打赌布朗先生会很高兴看到我们的照片。我们去给他看看！
Thanks for joining us on SciShow Kids! If you want to keep learning and having fun with us, make sure you hit the subscribe button, and we'll see you next time here at the fort!
感谢收看儿童科学秀！如果你想继续学习并和我们共度美好时光，请点击订阅按钮，咱们下期城堡见!
