Leonardo da Vinci designed an early underwater breathing apparatus known as a diving suit.
His early-16th-century drawings show a diver supplied with air through tubes connected to a floating structure. The design included a mask and a system intended to keep the diver underwater while allowing breathing. Some versions are associated with a protective suit and a container for collecting urine during a long immersion.
Leonardo proposed the apparatus for covert military operations, such as damaging enemy ships or cutting underwater obstacles. It was a theoretical design, and there is no reliable evidence that Leonardo’s complete suit was built or tested in his lifetime.
The concept should not be confused with modern scuba equipment. Leonardo’s diver depended on surface-connected air tubes, whereas scuba divers carry compressed gas cylinders. The design is nevertheless important in the history of diving because it treated underwater breathing as a mechanical engineering problem.