European monks would take a piece of clear rock, often quartz, and place it on top of the reading material.

欧洲的僧侣们会拿一块透明的石头，通常是石英，放在阅读材料的上面。

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The clear rock magnified the letters, making them appear larger, it's like what happens when a drop of water falls on something, whatever's below the drop of water appears larger, right?

透明的岩石放大了字母，使它们看起来更大，就像一滴水落在什么东西上，在这滴水下面的东西看起来更大，对吧？

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You can see a clear line where the black rock becomes white.

你可以看到一条清晰的线条，在那里黑石头变成了白色。

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Up in the mountains are clear lakes, quick-moving small rivers, and huge formations of rock.

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