The iron locking pins were four feet long, forged from solid three-inch wagon axles, and weighted at the butt with lead collars so they would drop through the guide sockets with the authority of an executioner’s blade.
Alden Bram stood on the lower sill platform, five paces from the groaning timber grate. The master mason had discarded his ash cane, leaning his broad chest against the secondary iron lever that controlled the exterior locking dogs. His wool sleeves were rolled to the shoulders, his thick forearms smeared with black graphite grease, his breath coming in short, rhythmic rasps that cut through the sulfur reek of the blown portal.
“Jon!” Bram bellowed over the metallic din echoing from inside the tunnel. “Take the sledge! Drive the south wedge home before the counterweight settles!”
Jon sprang from the wooden staging onto the stone sill. The flags were slippery with frost and shattered lime mortar, but his boots found purchase against the chamfered edge of the granite threshold. He swung the twelve-pound sledge horizontally, striking the head of the three-foot iron locking dog with all the leverage in his hips.
CLANG.
The heavy iron dog plunged four inches into the socket cut into the living bedrock.
