The Invisible World

Here's the craziest thing about glass: it can actually bend light! Most people think you need expensive, complicated, modern machinery to see the microscopic world. But long ago, people figured out that a simple piece of glass shaped like a lentil seed—thick in the middle and thin at the edges—changes how light hits your eye, making tiny things look huge. Even a simple round-bottom flask filled with water acts like a magnifying lens! What do you think happens to the path of light when it passes through the curved water flask?