Leonardo da Vinci specified leather for the suit in his early diving-suit design.
Around 1500, Leonardo sketched equipment intended to allow a diver to remain underwater. The suit was conceived as a waterproof leather garment, combined with a breathing system connected to the surface by tubes. A mask and other supporting equipment were also part of the concept.
The design appeared in the context of military plans for underwater operations. Leonardo imagined divers damaging or attacking enemy ships, although there is no reliable evidence that his complete apparatus was constructed and used operationally.
The invention is sometimes described as a modern scuba suit, but that is misleading. Leonardo’s arrangement depended on surface-linked air tubes, while scuba equipment carries a compressed-air supply. His sketch was an influential early diving concept rather than a modern self-contained system.