Gas holder

A gas holder is a big round tank that holds gas. Imagine a balloon that's really, really big and made of metal instead of rubber. Gas holders were used a long time ago when people needed to store gases like methane and hydrogen.

Back then, they didn't have pipelines or trucks to transport gas to homes and businesses, so they needed something that could store lots of gas in one place. Gas holders looked like big tanks or towers and they were a really important part of making sure people had enough gas to power lights and heat their homes.

The way a gas holder works is pretty cool. When gas is pumped into the holder, it fills up the empty space inside the tank. But since gas is really light and wants to rise up, the top of the holder starts to go up too. This happens because the pressure of the gas inside the holder is greater than the pressure of the air outside.

So, the gas holder can be raised or lowered depending on how much gas it's holding. If it's really full, it will be at its highest point. If it's almost empty, it will be at its lowest point.

Today, we don't use gas holders as much because we have pipelines and trucks that can transport gas more easily. But they were an important part of our history and helped make sure people had the energy they needed to live and work.