Diving bell

gas filled chamber for transporting divers vertically through the water

A diving bell was an early system for underwater diving. The basic idea of a bell is that a hollow object, even with an open bottom, will hold air when put under water (this can be seen with a glass in a sink). If the bell is heavy enough it will sink below the water. A swimmer can be inside the bell and breathe, or hold his breath and swim outside the bell for a short time, and come back to the bell to breath again. The idea had been around for a long time, but became useful in the 1600s.[1] Scuba diving has mostly replaced diving bells although they are still used sometimes.

Franz Kessler Wasserharnisch 1616

References

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  1. Alex Brylske. "A Brief History of Diving: Free Divers, Bells and Helmets Part I". Dive Training. Retrieved 14 April 2015.