These were two potential PODs for early submarine warfare that I didn't expect to see!There were a number of successful trials, but Napoleon cancelled the project after visiting at a point where Fulton had disassembled the submarine, and deciding (despite eyewitnesses) it had all been a fake by a charlatan. The annoyed Fulton tried to take his invention to Napoleon’s enemy Britain instead, but the Royal Navy was not interested
There were a lot of things proposed (or used in a limited way) in the Napoleonic Wars that seem way too modern out of context - gas warfare, rockets and so on. I often feel the 'weird Napoleonic-era superweapon Luftwaffe '46 style' genre is underdone; one of Patrick O'Brian's earlier Aubrey-Maturin novels is set on a failed superweapon rocket ship that has been (badly) converted back to a conventional one. A lot of stuff in LTTW was basically me taking some of this and turning up the knob (as with the Chappe semaphore and the Cugnot steam tractors).These were two potential PODs for early submarine warfare that I didn't expect to see!