What was Leonardo da Vinci’s underwater breathing apparatus commonly called?

Leonardo da Vinci’s underwater breathing apparatus is commonly called Leonardo’s diving suit.

Leonardo described a diving apparatus in the early sixteenth century, probably while working in Venice. The equipment was intended to let divers remain underwater for military operations, such as secretly damaging enemy ships. His drawings show a mask connected to breathing tubes that reached above the water’s surface.

The design included a leather suit and a system associated with a floating structure. Some versions of the reconstruction tradition also include a container for air and a means of dealing with the diver’s waste. Leonardo kept the apparatus secret because he feared it might be used for destructive purposes.

It is often called an early diving suit, but it was not a self-contained scuba system. The breathing tubes depended on air from above the surface, unlike modern scuba equipment, which carries compressed gas. No surviving evidence shows that Leonardo tested the device.