I restore this fire extinguisher from 1900 and test it. The fire extinguisher has lots of damage, it's oxidized, the bottle on the inside is broken, the hose is unusable and there are some dents. I've wanted to have one of these for a long time because the mechanism they use is so interesting. Also they look really nice. These type of extinquishers are called soda acid extinquishers. They use water that has soda in it and a small bottle of acid. When the extiguisher is flipped upside down, the soda and acid mix generating CO2 that will cause pressure to build in the extinguisher and that forces the water out.