Ever the military engineer, da Vinci generated designs for scuba gear that would allow for sneak attacks underwater during his time spent devising plans to defend the city of Venice. He believed soldiers with special equipment for diving (see picture) and with a breathing apparatus could be an effective method to sabotage enemy ships. The original concept for scuba gear was comprised of a leather suit and a mask with tubes attached to a cork floating on the surface of the water. However, this idea never really reached fruition, and is an example of one of da Vinci’s inventions that appeared too far-fetched for the people of the time to entertain. Luckily for Venice, they were able to thwart enemy forces before a need for such underwater warfare would have been necessary. The ingenuity of his scuba suit and original air bladder to aid with breathing was eventually explored by Jacques Cousteau who constructed the first aqua-lung model with Émile Gagnan that aided in the beginnings of deep sea exploration.

Sources:

“Scuba Gear.” Leonardo Da Vinci's Scuba Gear Invention, 2008, www.da-vinci-inventions.com/scuba-gear.aspx.

Campbell, Shawn. “Da Vinci's Scuba Gear.” Leonardo Da Vinci's Life, www.davincilife.com/scuba-gear.html.

Image Source : Permission granted by The British Library (https://www.bl.uk/onlinegallery/features/leonardo/diving.html) for use under the public domain and is attributed to the model-maker Simon Sanderson, from a design by Scott Cassell.