Dewey Lambdin’s naval hero, Alan Lewrie, has a way of collecting unique weapons. He owns a pair of double barrelled Manton dueling pistols and a Ferguson rifle.
In The Captain’s Vengeance, he adds yet another. The Girandoni air rifle.
Around 1779 a Tyrolean clockmaker named Bartholomäus Girandoni developed a revolutionary longarm based on compressed air. The firearm, if it could be called such, was about the size (4 feet long) and weight (10 pounds) of regular muskets but it had a magazine which held twenty .51 caliber lead balls and it could fire them out to about 150 yards. Its muzzle velocity was about the same as that generated by the modern .45-caliber ACP cartridge.
It was powered by a reservoir that could fire 30 rounds before it had to be changed.
The advantages of no smoke to reveal the position of the shooter, quietness, and a 20 round magazine impressed even the hidebound Austrian army. In 1780 the adopted it for service.
Unfortunately, the manufacturing processes of the day doomed the Girandoni to the ranks of historical curiosities. The neck of the air reservoir was weakly threaded. Only leather was available for gaskets. The reservoir had to be pumped 1500 times, by hand, to recharge it. In general it was very susceptible to damage and difficult to repair. By 1815 it was gone.
The video above is a great animation of how the Girandoni worked. This site has lots of photos of the actual rifle and its components.
As Americans we have our own link to the Girandoni. The Lewis and Clark Expedition carried one of them across North America.