This was amazing find. I really am a nerd in this subject but had no idea compressed air was used in the 18th century. This really changed my thinking and historical perspective. You blew my Sunday that I will forgive. I will blow all next weekend trying to figure out why compressed air didn't catch on wtf. From my (limited!!) research the valves were super expensive and took an amazing amount of craftsmanship - which didn't allow for mass production (eg Brown Bess).
There are all kinds of variants, including BB guns that are fully automatic. https://www.airgundepot.com/automatic-bb-guns.html
Air rifles 200 years ago were so effective (quiet, 30 round magazine) that Napoleon supposedly ordered that anyone carrying one be summarily executed. https://notorc.blogspot.com/2006/08/short-history-of-air-rif...
It was common in the US to do "plinking" with a BB gun at various targets, including windows of abandoned buildings, tin cans, and the unfortunate small animal. Probably still is in more rural areas. Anyway, different tradition than a weapon of war.