Also from wikihahahahahapedia, it took 1500 (!!!) strokes of the pump to charge one air reservoir. That was good for 30 shots.
And people wonder why gunpowder was more common ...
Air guns did have a few advantages, such as no powder smoke and usefulness in the rain. Also, once L&C’s air gun was pumped up it would shoot 22 shots quickly without having to reload. As you say, though, pumping up the reservoir was not quick.