EDIT: Please note that apparently the Priestel book I used as a major source for this video is partially incorrect, in that Pauly did create a traditional percussion system in France. The fire piston / diesel system was done slightly later after he moved to England, perhaps to avoid the Forsyth patent there.
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Samuel Pauly is the largely unrecognized father of the modern self-contained cartridge. In 1808 he patented a cartridge with a metal base that held a priming compound and attached to a paper or metal cartridge body holding powder and projectile. He followed this with an 1812 patent for a gun to fire the cartridges. What makes Pauly’s original system particularly interesting is that he did not use mechanical percussion (ie, hammer or striker) to ignite the primer compound, but rather a “fire pump”. A spring loaded plunger compressed air on top of the primer, heating it enough to detonate the compound in the same way that a diesel engine works. This was not a commercially successful system, though, and Pauly left Paris for London in 1814.

Pauly’s shop was taken over by Henri Roux, who continued making guns under the Pauly name while also improving the cartridges. These two pistols were made around 1820 and use a Roux cartridge with a mechanical striker hitting the primer compound in a Pauly-style cartridge case.

For more information, I recommend Georg Priestel’s free book “Jean Samuel Pauly, Henri Roux, and Successors - Their Inventions From 1812 to 1882” available here:
https://aaronnewcomer.com/document/jean-samuel-pauly-henri-roux-and-successors-by-george-priestel/