Leonardo da Vinci sketched a diving suit around 1500 as a protective underwater outfit for military divers.
His design included a sealed leather suit, a mask, breathing tubes, and a system intended to supply air from the surface. The tubes were connected to floating bell-like structures, while the diver’s body was protected from cold water and pressure. Leonardo’s notes placed the idea in the context of underwater operations near Venice.
The concept was not the same as a modern scuba suit. It depended on surface air and did not include a compressed-air cylinder carried by the diver. Leonardo also worried that the equipment could be used for covert attacks, so the design was reportedly kept secret.
Historians debate how practical the exact arrangement would have been. Nevertheless, the sketch is an important early example of a proposed diving suit, centuries before reliable underwater breathing equipment became available.