Found this about the Hilton Head Steamgun. Nice illustration of the gun and a bit of details.
??
I remembered that the "Dynamite Cruiser" USS VESUVIUS used three steam guns to fire dynamite loads on Santiago, Cuba during the Span-Am War with good results. (Yeah, I love my Navy Odd Ducks as much as I love Odd Birds. LOL) But was still stripped of her guns shortly afterwards and converted to torpedos, only to be decommissioned a couple of years later.?
You might try hunting under "Dynamite Cannon or Gun" for more info.
?
Keep It FUN!
Dan G
Dan G