Cast Iron Naval Swivel Cannon, 18th – 19th Century Consign Now DeptCollections, Maritime ArtsSizeLength 22 in. Sold for $1,220 Cast Iron Naval Swivel Cannon, 18th – 19th Century, one inch bore, on custom base with cast bronze trunnion mounts and wood aiming handle. Length 22 in. Please note that this auction has ended. Click here for an overview of this auction.