Barometer

Hello! My name is Barometer. A long, long time ago, people looked up at the sky and felt very puzzled. They didn't know why one day the sun would shine brightly and the next day big, gray clouds would roll in with rain. It was a big mystery! They didn't realize the answer was all around them, in something they couldn't even see. It was the air! The air is like a giant, invisible blanket covering the whole world, almost like an ocean we walk through every day. A very clever man named Evangelista Torricelli was curious about this invisible air. He wanted to understand its secrets, and that is where my story begins.

My story began in the year 1643. That was the year Evangelista Torricelli brought me to life! He took a very long, skinny glass tube, which was closed at one end, and carefully filled it with a special liquid. It was a heavy, silvery liquid that wiggled and wobbled, called mercury. It shimmered like a little bit of moonlight caught in the glass. Then, he put his finger over the open end, turned the whole tube upside down, and dipped it into a bowl that also had some mercury in it. When he took his finger away, something amazing happened. Not all of the shiny liquid fell out. A long, silver line of it stayed inside my tube. Evangelista realized that the invisible air was pushing down on the mercury in the bowl. This push, which he called pressure, was strong enough to hold up the silver line inside me. The air had weight! I was so excited. I could feel the air's push. When the air pushed hard, my silver line stood up tall. When the air was being gentle and light, my silver line would sink down low. I finally had a way to show people the secrets of the air.

My most important job was to be a weather helper. I could tell people what the invisible air was up to, and that helped them guess what the weather would be like. I would tell them, “My silver line is high today. The air is heavy and happy. It's a good day for a picnic!”. When my line was high, it usually meant sunny skies. But if my silver line started to drop, it was like a secret message. “Watch out,” I'd whisper, “the air is getting lighter. Storm clouds might be coming to visit.”. A low line often meant rain or wind was on its way. Sailors on big ships would look at me before they went out to sea. If my line was high and steady, they knew the ocean would likely be calm. Farmers would check on me too. If they saw my line dropping low, they knew to bring their animals into the barn to stay safe and dry. I felt so proud to help keep people safe. Even today, hundreds of years later, I'm still helping. You can find my relatives in big weather stations and even carried by hikers climbing tall mountains. I am a Barometer, and I love my job of listening to the whispers of the wind.