In castle defense, an open gate was not an error. It was the most irresistible lure in military psychology.
Attacking infantry met twenty feet of unbroken granite castle walls. Then, their tactical instinct was to seek the path of least pushback.
If an outer gate hung slightly ajar, the human mind invariably chose the apparent weakness, rushing headlong into a prepared squeezing chamber.
From the overhead murder-hole gallery of the outer gatehouse, Giles Croft looked down through the two-foot iron floor grates.
Thirty feet below lay the raised stone road that spanned the outer moat.
The raised stone road was paved with dressed solid mountain stone, exactly twelve feet wide. It was flanked on either side by five-foot stone low roof walls.
Across that narrow stone bridge, Warlord Bronn’s main siege weapon was rolling forward under the rhythmic chanting of forty armored pushers.
It was a monstrous engine.
A thirty-foot balk of seasoned mountain oak, two feet in width, tipped with an eight-hundred-pound forged iron ram-head shaped like a snarling wolf skull.
The massive tree trunk was slung from heavy iron trace chains inside an arched timber carriage clad in double-layered green ox-hides.
Behind the ram marched one hundred and fifty elite shock troops. Veteran hired blades in heavy black ringmail, carrying broad-bladed axes, morningstars, and iron crowbars.
At the entrance to the raised stone road, the outer wooden gates of Grey Crag hung five inches open. He swung gently in the bitter winter wind.
Before the enemy reached the raised stone road, Giles had inspected the stonework vault of the outer gatehouse hall with Master Duncan Stone-Splitter.
The ceiling above the entry hall was not a flat timber floor. It was a three-foot-thick catenary barrel arch built of solid water-setting concrete faced with close-jointed granite arch stones.
“Check the vault crown, Duncan,” Giles said, lighting up the stonework seams with his lantern. “When close-quarters canister discharges downward, explosive gas spreading generates an upward rebound blast wave. A flat timber floor would buckle upward and collapse the gun platform.”
“The arch redirects all upward pressure directly into the side abutments,” Duncan replied. He tapped the keystone with his hammer. “The harder the blast pushes up, the tighter the granite arch stones wedge together. You could set off twenty kegs of black powder in this hall and the ceiling wouldn’t drop a pinch of sand.”
At the rear archway, Master Caleb Thorne-Wood was adjusting the balance weight mid-air for the outer drop-gate.
The heavy gate was suspended by twin forged iron link-chains passing over grooved bronze pulleys four feet in width.
“Net downward gaining speed math,” Giles explained to Toby Karr, who was holding the chalk-reel. “The drop-gate weighs three thousand pounds. The lead balance weights in the side chases weigh two thousand four hundred pounds. That leaves an unbalanced downward crushing weight of six hundred pounds.”
Toby noted the figures on his slate.
“Six hundred pounds of net force over a sixteen-foot drop yields a gaining speed of six point four feet per second squared,” Toby recited proudly. “Total descent time is exactly one point four seconds.”
“Correct,” Giles said. “In one point four seconds, no human being can react, reverse direction, and clear the threshold.”
Beside Giles in the overhead gallery, Captain Kenneth Drake held a heavy iron pry-bar, his eyes fixed on the advancing engine.
“They’re taking the raised stone road, Lord Giles,” Kenneth whispered. His breath clouding the was cold air. “Not a single man is looking at the walls. Every eye is on that open doorway.”
“Algorithmic pathfinding,” Giles murmured, checking his stop-watch. “Faced with an obstacle height of eighteen feet and an open passage width of five inches, the target AI calculates that breaching the timber door needs eighty percent less moving effort than scaling the castle walls.”
Kenneth glanced sideways at Giles, shaking his head with quiet admiration.
“The AI,” Kenneth whispered to himself, convinced that Giles was referring to an ancient, forgotten doctrine of siege arithmetic. “The Lord Baron has calculated the very thoughts inside their skulls.”
Below them on the plain, Warlord Bronn rode his black destrier to the foot of the raised stone road.
The warlord’s eyes widened behind his horned steel visor as he spotted the unlatched gates.
“The cowards broke,” Bronn bellowed, his voice carrying like a battle-horn across the frozen ditch. “Their gate is unbarred. They fled inside to hide in their cellars.”
He raised his flaming greatsword, pointing the fiery tip straight through the gap.
“Ram crew, charge the opening,” Bronn roared, spurring his horse. “Plow the ram through. Take the entry hall. Clear the gate.”
The forty pushers threw their collective weight against the timber carriage struts, their iron-cleated boots digging into the granite flags.
The three-ton engine sped up, the heavy iron wheels rumbling like thunder across the stone bridge.
Behind the rolling timber castle, one hundred and ten armored shock troops surged forward in a dense, packed finger bone.
They crowded onto the twelve-foot raised stone road, tightly packed between the stone low roof walls until they marched shoulder to shoulder, four ranks deep.
The nose of the iron ram struck the outer oak gate.
CRASH.
The unlatched doors swung inward, rebounding against the stone walls with a hollow boom.
The three-ton ram rumbled across the threshold. It rolled directly into the enclosed outer gatehouse entry hall.
The chamber was ten feet wide, thirty feet long, and twenty feet high, built entirely of massive stone water-setting concrete faced with smooth granite cut stone.
At the far end of the hall, twenty feet ahead, stood their obstacle.
The inner drop-gate.
It was a huge grid of four-inch square iron bars. It was backed by seasoned oak balks, fully lowered and seated three inches into a recessed granite threshold doorstep.
Behind the iron grid stood Captain Kenneth Drake and ten guard post guards, shields braced and broadswords drawn in silent, unmoving formation.
Through the heavy iron grid of the inner drop-gate, Captain Kenneth Drake stepped forward. He held his ten-foot iron-shod pacing rod across his chest.
His voice rang through the enclosed stone hall like a funeral bell.
“Broken Horn ram crew, halt where you stand,” Kenneth commanded with stern, unbending power. “You have entered a closed town holding zone. Drop your axes, step back from the ram, and surrender your weapons. If you yield now, your lives are protected under settlement law.”
The scarred giant sub-chief burst into a roar of mocking, bloodthirsty laughter.
“Surrender to ten frightened town constables behind an iron grate?” the sub-chief sneered, brandishing his double-bitted war axe. “We have an iron ram that breaks castle keeps, little boy. We’ll batter your grate into scrap, cut your heart out, and hang your carcass from the low roof wall.”
He turned back to the forty pushers, roaring at the top of his lungs.
“Take the ropes, dogs. Draw back the ram. Smash their teeth in.”
Behind the inner grate, Kenneth turned his head upward toward the murder-hole slot, his jaw set like granite.
“Parley refused, Lord Giles,” Kenneth called out quietly. “They demand the iron.”
One hundred and ten shock troops poured through the open outer gateway, packing into the thirty-foot hall until the entry hall was filled with a dense, heaving mass of steel armor, horned helmets, and drawn weapons.
From the overhead gallery, Giles Croft leaned over the central murder-hole grating.
He looked down into the sea of black iron helmets packed twenty feet below.
Beside him, Master Caleb Thorne-Wood stood by the emergency balance weight release. A forged steel dog-leg catch pin held in place by a heavy bronze cotter ring.
“Target thickness confirmed,” Giles said in his calm, unbending engineer’s voice. “Entry hall volume occupied to ninety-five percent load-bearing capacity.”
He looked at Caleb.
“Trip the outer drop-gate.”
Caleb brought an eight-pound wooden mallet down upon the release pin.
CLACK.
The bronze cotter pin snapped away.
In the ceiling slots of the outer archway, forty feet of forged iron chain whipped through bronze pulley wheels with an ear-splitting, shrieking scream.
A one-and-a-half-ton drop-gate of solid cured oak, sheathed in heavy sheet iron and weighted with three hundred pounds of cast lead pigs, dropped straight down its upright stonework channels.
CLANG-THUMP.
The iron-shod bottom timbers slammed into the granite threshold with the moving violence of a guillotine.
The impact shook the entire gatehouse foundation. It sent a shower of stone dust across the entryway.
The massive iron grid sank two inches into the recessed stone doorstep. There, four spring-loaded steel dogs snapped shut over the bottom bar. It locked the gate permanently into the bedrock.
A sudden, choking silence fell over the crowded entry hall.
The raiders at the rear spun around, their faces draining of blood.
Where the open mountain plain and daylight had been a heartbeat ago, there was now only an iron-hard wall of solid iron bars and locked oak balks.
“The gate,” a raider whispered, throwing his shoulder against the iron grid. “The rear gate dropped. We’re locked in.”
The giant sub-chief at the front turned his head, his eyes widening in sudden, animal panic.
He looked at the solid inner iron drop-gate blocking their advance.
He looked back at the locked outer drop-gate blocking their retreat.
Then he looked up.
On the upper firing platform, Toby Karr was inspecting the air-flow angled slats built into the outside low roof wall.
“Six smoke relief chimney pipes,” Toby reported. He ran his wooden gauge through the narrow slanted stone slots. “Cut on a sixty-degree incline through the north and south stonework faces.”
“Burning gas management,” Giles explained to the boy. “Discharging five pounds of black powder in an enclosed space produces over seventy cubic feet of carbon monoxide, cold air gas, and boiled away sulfur. Without high-volume heat-rising venting, the upper gallery crew would succumb to toxic gas asphyxiation within ninety seconds.”
Borin adjusted the braided linen lanyards, checking the friction igniters fitted into the flash holes.
“The igniters are dry as desert sand,” Borin grunted, tapping his brass priming horn. “Crushed meal powder blended with ten percent crushed stibnite. When you pull the ring, it throws a five-hundred-degree spark straight into the main charge in twenty-five split seconds flat.”
Twenty feet above their heads, the smooth vaulted granite ceiling was pierced by four deep, box-shaped openings.
Murder holes.
Through the heavy iron gratings of the ceiling slots, the scarred sub-chief didn’t see daylight.
He saw the glowing red embers of charcoal fire bowls.
He saw the dark, bearded face of Master Borin Bronze-Lung. He looked down with grim, measuring eyes.
And directly lined up above the center of the heaving crowd, he saw the flared bronze muzzles of two heavy siege engines.
“Trap,” the sub-chief screamed, his voice cracking in terror. “It’s a trap. The rear gate is locked. Smash the front grate. Swing the ram. SWING THE RAM.”
The forty pushers threw their collective weight onto the swinging ropes in wild, desperate panic.
Behind the inner iron drop-gate, Captain Kenneth Drake and his ten guards braced their shields. They set their boots against the granite floor.
Up in the gallery, Giles Croft stood over the murder holes, his wooden ruler in hand. He watched the three-ton oak ram swing backward to strike.
“Load-bearing impact test starting,” Giles said calmly. “Let’s see if our water-setting concrete arch buffers meet squeezing specifications.”