Chapter 20: The Teeth of the Mountain

The heat of July had turned the stone of the Casbah into a furnace that radiated
the sun's warmth long into the mountain night. Inside the drafting room, by the
light of three oil lamps that flickered in the hot draft, Amine laid out the
parchment that would define the third, most lethal circle of his defense.

"Traditional artillery, Yusuf," Amine said, his brass divider tracing the bore
of a short, thick-walled cannon, "is an exercise in hope over mathematics. A
French twelve-pounder field gun fires a solid iron ball that weighs twelve
pounds. Because the ball is round and smaller than the bore, it bounces inside
the barrel, exiting with a random windage. At eight hundred yards, it has a
horizontal spread of nearly twenty paces. If the wind is strong, or if the
gunner's hand is slightly off, the ball hits nothing but the dirt."

Yusuf, whose shoulders were broader now from months of mountain riding and
training, leaned over the table. "But Sidi, the French have hundreds of these
guns. They have the Canon de 8 and the Canon de 12. In Algiers, our batteries
have the heavy Turkish bronze guns, but they are too heavy to move. If we cannot
match their weight, their batteries will tear our infantry to pieces before we
can reach them with our rifles."

"We do not need to match their weight, Yusuf," Amine said, a cold, sharp light
in his eyes. "We are going to match their precision. We are going to build a
rifled muzzle-loading field gun—the Zilzal—the Earthquake."

He tapped the drawing of a long, elegant bronze barrel, its interior marked with
six deep, spiral grooves.

"By rifling the barrel of a field gun, we can fire a cylindrical-conical shell
instead of a round ball. A conical shell of the same caliber weighs twice as
much as a round ball, and because it spins in flight, its trajectory is
perfectly straight. At fifteen hundred yards—nearly twice the range of the
French smoothbores—our horizontal spread will be less than two paces. We will
hit their gun-crews before they can even unlimber their carriages."

"And the shell, Sidi?" Lounes asked, his single eye fixed on the drawing of the
projectile. "It is hollow?"

"It is hollow," Amine said. "Made of thin, cast iron, filled with a bursting
charge of our glazed powder. But we are not going to use the traditional wooden
fuzes. The European gunners must cut their wooden fuzes to length with a knife,
estimating the time of flight based on the distance. If the calculation is
wrong, the shell explodes too early in the air, or too late when it has already
buried itself in the mud."

He showed them the detail of the nose of the shell.

"This is an impact percussion fuze," Amine said. "Inside the brass nose-cone is
a small, heavy brass plunger—the striker—held in place by a thin copper wire,
the safety pin. When the cannon fires, the massive forward force keeps the
plunger locked in place. But when the shell strikes the ground, or the walls of
an enemy carriage, the sudden deceleration shears the copper wire. The plunger
flies forward, striking a copper percussion cap on a steel nipple, igniting the
main powder charge instantly. The shell will explode upon impact, turning the
iron casing into a storm of five hundred jagged fragments."

He looked at Lounes. "To make this, we must cast the barrels from gunmetal—an
alloy of ninety parts copper and ten parts tin. It is tougher than cast iron,
less prone to bursting under high pressure, and easier to cast cleanly with our
current furnace capacity. But we must avoid the great mistake of the Turkish
bronze-founders."

"And what is that, Sidi?"

"Segregation," Amine said. "When copper and tin are melted together, they do not
cool at the same temperature. If the liquid metal cools too slowly inside the
mold, the tin will separate from the copper, rising to the surface and forming
soft, spongy pockets of 'tin-sweat' that will fail under the shock of
detonation. To prevent this, we must cast the gun vertically, breech-down, in a
deep pit-mold, with a massive 'deadhead' at the top."

He pointed to the top of the mold drawing.

"The deadhead is an excess height of thirty centimeters of molten metal. The
immense weight of this upper column of liquid will compress the bronze below,
forcing any gas bubbles or impurities to rise into the deadhead, while the lower
barrel cools into a dense, uniform, flaw-free mass. Once the metal is cold, we
will saw off the deadhead and discard it, leaving a perfect cylinder of
gunmetal."

The casting pit was dug into the floor of the foundry, three meters deep and
lined with thick walls of firebrick.

Inside the pit, Lounes and Meziane spent three days assembling the mold. It was
made of a mixture of fine river sand, fireclay, and cow-hair, rammed tight
around a hollow wooden template of the cannon's exterior. The mold was then
baked for twenty-four hours by a charcoal fire built inside the pit to dry out
every trace of moisture.

"The copper is ready, Sidi," Meziane said, his face red from the heat of the two
large crucible furnaces that sat on either side of the pit.

Inside the furnaces, eight hundred pounds of pure copper from the Soummam mines
and eighty pounds of refined tin were melting in deep graphite-clay crucibles.
The heat was immense, a brilliant, pale green flame—the sign of burning zinc and
tin impurities—dancing over the surface of the liquid metal.

Amine stood by the pit, his hand resting on the lever of the overhead iron
crane. "The temperature must be exactly one thousand one hundred degrees,
Lounes. If it is too hot, the tin will burn away. If it is too cold, the liquid
will freeze before it fills the narrow breech at the bottom of the mold."

He watched the metal. The surface of the molten bronze had turned into a smooth,
swirling mirror of liquid gold, free of any slag or crust.

"Pour!" Amine called.

Yusuf and Meziane engaged the gears of the crane. The first massive graphite
crucible was lifted from the furnace, its weight turning the heavy iron chains
into a tight, ringing song. They swung the crucible over the mouth of the
vertical pit-mold.

Lounes took a long iron rod, skimming the last traces of dross from the lip.

"Now," Amine said.

They tilted the crucible.

A stream of liquid white-gold bronze poured into the mold.

The heat that rose from the pit was so intense that the dry sand on the floor
began to hiss, and the workers had to shield their eyes from the brilliant,
blinding light. The liquid metal filled the narrow breech, rising slowly through
the cylindrical shaft of the mold until it reached the top of the brick lining.

"The second crucible!" Lounes roared, his voice hoarse from the smoke.

They swung the second vessel, pouring the remaining bronze directly into the
mold until the liquid rose thirty centimeters above the cannon's
muzzle-line—filling the deadhead.

"The pour is complete," Amine said, looking down into the glowing brick well.
"Do not disturb the sand. It must cool slowly, under the earth, for forty-eight
hours."

Two days later, the crane lifted the heavy, blackened mass from the pit.

Lounes took a heavy hammer, striking the baked clay shell. The mold shattered
and fell away in a cloud of gray dust, revealing the solid, raw barrel of the
cannon.

It was an imposing piece of metal, nearly two meters long, its surface a rough,
dull gold-brown. At the top was the thick, rough cylinder of the deadhead, its
surface pitted with the bubbles and impurities that had been forced out of the
barrel below.

They carried the barrel to the new, steam-powered horizontal lathe.

The Cornish steam engine was running at full pressure, its heavy flywheel
turning with a steady, rhythmic whoosh-thump. Amine engaged the gears of the
boring carriage.

A massive steel saw, driven by the steam engine's torque, was positioned at the
muzzle-line.

Skrrrrt-clack.

The steel teeth bit into the bronze, a stream of soap-water cooling the joint.
Within an hour, the heavy, ugly deadhead was cut clean away, falling onto the
floor with a heavy, metallic thud.

The face of the muzzle was revealed. It was a perfect, flawless ring of pale
gold bronze, completely solid and free of any pinholes or soft spots.

"Now, the bore," Amine said.

The solid barrel was clamped to the spinning spindle of the lathe. The
stationary boring bar, carrying its circular cutter-head with six adjustable
steel teeth, was advanced slowly into the bronze core by the gravity-weight feed
system.

Shhh-screeech.

For eight hours, the steam engine drove the lathe, the heavy steel teeth slowly
eating their way through the solid bronze. A continuous stream of curly, golden
bronze shavings spiraled out from the bore, falling into a wicker basket below.

When the boring was complete, the barrel was moved to the rifling bench.

The rifling of a cannon was more difficult than that of a rifle. The six grooves
had to be wide, shallow, and have a progressive depth—shallower at the muzzle to
prevent the shell's lead studs from stripping.

Amine had Lounes mount a heavy iron helical guide-rod to the bench. The cutter
was a solid disk of steel carrying six small, adjustable cutting teeth, which
was pulled through the bore by a heavy iron cable connected to the waterwheel's
main winch.

They ran the cutter through the barrel eighty times, index-rotating the cutter
after each pass.

By the end of the week, the first Zilzal barrel was finished.

The interior was a brilliant, mirror-bright cylinder of pale gold, its six
spiral grooves winding their way to the breech with a majestic, geometric
precision.

"The shell must be cast from hard iron, Lounes," Amine said, standing by the
assembly table.

On the table before him was the first projectile—a long, cylindrical-conical
iron shell. On its sides were six small, circular buttons of soft zinc, cast
directly into matching recesses in the iron walls.

"These are the studs," Amine explained, pointing to the zinc buttons. "When the
soldier loads the shell from the muzzle, the zinc studs align with the six
spiral grooves of the rifling, sliding down the barrel easily. When the gun is
fired, the zinc studs follow the spiral of the grooves, forcing the heavy iron
shell to spin as it exits the muzzle."

He held up the brass nose-cone of the percussion fuze.

"This is the safety pin," Amine said, showing Lounes a tiny wire of soft,
unalloyed copper that passed through the center of the brass plunger, holding it
back from the steel nipple. "It is strong enough to hold the plunger steady
during the rough transport on the mountain roads. But when the shell strikes a
hard surface... the impact will shear this thin wire instantly. The plunger will
strike the copper cap, and the shell will explode."

He assembled the fuze, screwing the brass nose-cone into the threaded opening at
the tip of the iron shell.

"We have two guns finished, Yusuf," Amine said, looking up at the sergeant. "And
fifty shells ready. Let us carry them to the high ridge. We will see if the
Zilzal can speak to the valley."

The test was conducted on a high, bare limestone ridge overlooking the dry basin
of the lower valley, three thousand yards from the fort.

The cannon had been mounted on a heavy, low-slung carriage of mountain oak, its
wheels bound with thick iron tires, designed by Amine to absorb the immense
recoil of the rifled charge.

Yusuf and three of the new Kouloughli gunners stood by the breech. They had been
trained in the loading sequence, their movements silent, rapid, and disciplined.

"Load the charge," Yusuf ordered.

A soldier pushed a silk bag containing two pounds of their new glazed rifle
powder down the muzzle.

Meziane stepped forward, carrying the heavy iron shell. He aligned the six zinc
studs with the grooves at the muzzle. With a smooth, metallic shhh-thunk, the
shell slid down the rifled bore, its studs spinning along the spiral of the
bronze walls until it seated firmly against the powder bag.

"Prick the cartridge," Yusuf said.

A gunner pushed a long brass needle down the vent-hole at the breech, piercing
the silk powder bag. He then screwed a small copper percussion tube—similar to
their rifle caps—into the vent.

Amine stood thirty paces to the side, his achromatic telescope mounted on its
brass tripod, focused on an old, dry-stone shepherd's hut that sat on a ridge
two thousand five hundred yards away. To the naked eye, the hut was a tiny gray
speck, barely visible against the white limestone.

"Sights at two thousand five hundred," Amine said, his hand adjusting the brass
elevating screw at the breech of the gun. The barrel rose slowly, its
gold-bronze muzzle pointing up into the blue sky.

"Clear the breech," Yusuf called, his hand holding the long lanyard connected to
the percussion lock of the vent-hole.

He looked at Amine.

Amine nodded.

Yusuf pulled the lanyard.

BOOM.

The report of the Zilzal was a thunderous, cracking roar that shook the very
limestone beneath their feet, far louder than the smoothbore guns Yusuf had
heard in Algiers. A massive, clean cloud of white smoke erupted from the muzzle,
and the heavy oak carriage recoiled backward three paces, its iron brakes biting
into the dirt.

Amine's eye was fixed on the lens of his telescope.

The shell was traveling at nearly eleven hundred feet per second, its flight
silent and invisible as it spun through the high mountain air.

For five long, agonizing seconds, the valley was silent.

Then, through the lens, Amine saw the old shepherd's hut disappear.

A brilliant, orange-red flash of light erupted from the center of the stone
walls, followed instantly by a massive, boiling cloud of gray dust and black
smoke that rose thirty meters into the air. The sound of the explosion—a deep,
hollow CRACK—echoed back across the valley a second later.

When the smoke cleared, the shepherd's hut was gone. In its place was nothing
but a smoking crater of shattered limestone and black soot, the heavy stone
walls completely pulverized by the force of the shell's impact.

Yusuf dropped the lanyard, his face white, his mouth open in a look of profound,
superstitious terror. He had spent his life watching cannons fire solid iron
balls that did nothing but bounce through the dirt, chipping a few stones or
breaking a wooden cart. He had never seen a weapon that could destroy a stone
fortress in a single second from two miles away.

"By the teeth of the wolf," Yusuf whispered, his hand trembling as he reached
out to touch the hot gold-bronze of the barrel. "This is not a gun, Sidi Amine.
This is the hand of God."

"This is the hand of metallurgy, Yusuf," Amine said, his voice quiet, his eye
still fixed on the smoking ruins through his telescope. "With six of these guns,
we can hold the high ridges against any army the French can land. They will
never see the walls of Hamza."

He turned to look at the workshop, where the smoke of his engine was rising into
the blue sky.

"The third circle is complete. Now, we must prepare the final strategy for the
invasion."