The Floating Air Gun
I found this bit of history interesting:
Forum Janitorial Services Specialist
Thanks for the additional information. I was curious how much pressure was used to launch a 15 inch projectile. 1000 psi on that scale seems like a lot of pressure for the 1890's.
A bit more information about a different airgun (this one a practical application) with good "service history":
Scroll down to the details of the Haida.
As Bill would put it:
"There are more things in heaven and Earth, Horatio, / Than are dreamt of in your philosophy"
Keep well and shoot straight!