Xiao Heng’s Steel Whip lay across his knees, its tip wrapped in silk soaked in soapberry water, shimmering with a greenish hue in the moonlight. "The ship planks discovered at Ghost-Head Reef three days ago have been verified by the Directorate of Imperial Manufactories as belonging to a treasure ship from the Yongle era. But how can you be certain, Miss Shen, that the hold contains the Ministry of Works' classified archives?"
Shen Xitang unfolded a silk handkerchief from her sleeve, revealing a charcoal-rubbed imprint of wood grain. "This is a fragment of the desk salvaged from my father's study after the fire. If you observe the cracks in the lacquer, My Lord, you will see that they are actually encrypted fire-seal patterns from the Ministry of Works."
Her fingertips traced the cobweb-like lines. "The intersection of these cracks marks the exact coordinates for the seventh day of the seventh lunar month in the Year of Guiyou."
Suddenly, hurried footsteps echoed outside the cabin, and Qingxing burst through the door, clutching a lacquer box. "Miss, an urgent dispatch from the Quanzhou Naval Fleet!"
Beneath a string of coral beads in the box lay a nautical chart. As candlelight hit the edges of the paper, hidden patterns emerged—the distinctive peacock feather watermark of the Ministry of Rites.
Xiao Heng flicked his Steel Whip, unfurling the chart in the breeze. Shen Xitang caught a faint scent of agarwood and abruptly pressed the parchment close to the candle flame.
As the ink heated, vermilion annotations appeared: "Wokou envoy fleet diverted to Hirado Island; suspected to be carrying three thousand piculs of sulfur." In the margins, where the handwriting was hurried, the faint indentation of a private seal belonging to a Vice Minister of the Ministry of Revenue could be seen.
"A clever ruse—'crossing the sea under a false banner,'" Xiao Heng remarked, measuring the route with the tip of his whip. "Hirado Island is only two days' sailing from Ningbo Port. If the Wokou are smuggling sulfur in with the tribute..."
Before he could finish, the ship jolted violently. Shen Xitang steadied herself against the porthole and saw countless indigo cloth bags bobbing on the surface of the sea—they were waterproof salt bags, a specialty of the Shen Family’s dyehouses.
Each bag, bloated and round, rose and fell with the waves, forming the shape of the Big Dipper Formation.
"It’s a tide-signal marker!" She snapped the string of jade beads from her wrist, and the agate stones rolled across the nautical chart. "These buoys automatically align during the full moon tide to guide ships away from the reefs."
Xiao Heng struck a brass gong with his Steel Whip, and twenty sailors sprang to adjust the cables. The treasure ship’s main sail turned slowly, catching the southeastern wind to steer directly toward the Ghost-Head Reef, indicated by the handle of the "Dipper."
Shen Xitang gripped a bronze key, hearing a faint sound of gears engaging within the keel—every mortise and tenon of this replica Xuanji had been restored according to the *Creation of Heavenly Works*.
At 3:45 AM, the moon hung at its zenith. Shen Xitang crouched by the ship’s rail as the receding tide revealed pitch-black reefs.
Seven bronze statues of Xuanwu stood half-submerged in the surf, their tortoise-shell patterns perfectly matching the bronze key. She inserted the key into the mouth of the largest Xuanwu, and the sharp click of a mechanical trigger startled the seabirds roosting in the night.
"Watch out!"
Xiao Heng wrapped his Steel Whip around her waist and pulled her back sharply. With a deafening roar, the reef split open, and rusty iron chains groaned as they hoisted a bronze chamber from the depths.
The copper nails studding the chamber door had long since oxidized to green, yet the tangled-branch patterns of the Ministry of Works’ fire-seal were still clearly visible.
"It is a secret document chest from the Yongle era." Shen Xitang wrapped her fingers in a silk cloth and lightly touched the bronze beast head on the door. "We must use the Seven Luminaries calendar to calculate the precise moment to unlock it."
As the first light of dawn appeared, the bronze chest finally swung open. Holding her breath, Shen Xitang retrieved the oil-cloth-wrapped archives; the yellowed rice paper bore structural diagrams for an improved Shenji Crossbow.
A vermilion note in the margin read: "Third year of Xuande: converted the crossbow mechanism into a loom, to be hidden at the Jiangning Imperial Textile Factory."
"So that’s it." Xiao Heng tapped a spot on the diagram with his whip. "The Shen family’s heirloom jacquard loom—its prototype was actually a Ministry of War crossbow mechanism."
Shen Xitang flipped through the papers and a piece of mulberry paper fluttered out from a hidden layer.
The paper was riddled with pinholes; when held against the rising sun, it revealed a map of the coastal defenses. On it, the site where the Shen family’s grain ships had sunk twenty years ago was marked with a bold vermilion circle.
"Look here, My Lord." She placed the mulberry paper over the nautical chart. "This red circle corresponds exactly to the current position of the Wokou envoy fleet."
Before she could speak, a warning cry came from the lookout tower. Seven black-sailed ships emerged from the mist, their figureheads carved with three-clawed pythons.
Shen Xitang gripped her modified Pear Blossom Rain Needle as she saw a flag signal lowered from the enemy mast—it was the cloud-pattern merchant flag of the Jiangning Imperial Textile Factory.
"Fire the signal rockets!" Xiao Heng pointed his Steel Whip toward the sky. "Order the Ningbo Navy to close in!"
In the heat of battle, Shen Xitang climbed the mainmast. A wooden crate on the enemy deck was struck by cannon fire, and the spilled sulfur stones glimmered with a sinister golden light in the morning sun.
She realized the truth instantly: using the mast as a compass and the sun as a square, she calculated that the Wokou fleet’s path was aimed directly at the salt fields of Hangzhou Bay.
"They intend to burn the official salt depots!" As she scrambled down from the mast, a stray arrow grazed her temple. "If the sulfur mixes with the salt piles, it will ignite the moment the tide rises..."
A world-shaking explosion erupted to the southeast, staining the sky red.
Watching the billowing smoke, Shen Xitang suddenly remembered the map of Hangzhou Bay in her father’s study, obscured by ink stains, with a small note in the margin: "Seventh day of the seventh lunar month, Year of Guiyou: the tide brings a curse."
"Change course!" She shoved the helmsman aside, his palms slick with cold sweat. "The Wokou are using the southeastern wind to drive the fire toward the Textile Bureau!"
The treasure ship cut through the waves, and Shen Xitang thrust the bronze key into the modified helm.
With the sound of interlocking gears, twelve modified crossbows slid out from the side of the hull—these were the "Flying Fire Meteors" she had restored according to the *Creation of Heavenly Works*, their arrowheads wrapped in cotton soaked in rock oil.
"Fire!"
Rockets rained down upon the enemy fleet like a meteor shower. The sea breeze fueled the flames, instantly creating a wall of fire.
Shen Xitang leaned against the rail, watching the Wokou soldiers abandon their ships and leap into the sea. A sudden sharp pain stung her wrist—the bronze key had cut her skin, and as blood seeped into the tangled-branch patterns, a section of encrypted Ministry of Works text appeared.
"So, the true secret chamber is in..." She looked up abruptly, seeing the seven bronze Xuanwu statues slowly rotating in the firelight, their tortoise-shell cracks forming the character "Tang."
Xiao Heng’s Steel Whip coiled around her wrist. "Miss Shen?"
"To the salt fields!" She tore off a piece of burning sailcloth. "That is where the last batch of the Ministry of Works’ Shenji Crossbows is hidden!"
As the morning light pierced the smoke, Shen Xitang stood amidst the ruins of the salt fields.
Beneath the charred salt piles lay crossbows forged from refined iron, the trigger mechanisms bearing the same tangled-branch patterns as Xiao Heng’s Steel Whip.
She traced the inscription, "Made in the nineteenth year of Yongle," on the crossbow arm, finally understanding the true meaning of the "Exploitation of the Works of Nature" seal in her father’s secret compartment.
"Miss, look!" Qingxing brushed away the broken tiles, lifting out a gilded box. Inside, the full volume of the *Creation of Heavenly Works* lay unharmed, with a vermilion note on the title page: "Third year of Xuande: converted crossbows to looms to quell the Wokou threat."
Shen Xitang looked toward the horizon where the sea met the sky, where twenty Ming warships were closing in.
She pressed the bronze key onto the hidden pattern on the last page. The page detached, revealing an imperial merchant’s gold seal tucked inside—the seal’s knob featured the Big Dipper, perfectly matching the old scar on her wrist.
The morning mist, thick with the smell of scorched earth, rolled over the salt field ruins. Shen Xitang crouched to pick up a handful of hot salt; a sharp sting bit into her fingertips.
The surface of the salt grains shimmered with a strange indigo hue—it was the Wokou’s secret formula, a type of sulfur-salt that exploded upon contact with water. She had seen records of it in a hidden compartment in the Shen family’s old account room.
"Movement in the salt pile at the southeast corner!"
Xiao Heng’s Steel Whip whistled through the air, coiling around a flying arrow.
Shen Xitang rolled behind a charred salt cart, seeing a cold glint flashing from the gaps in the salt pile thirty paces away—it was a five-bolt repeating Zhuge crossbow.
Such weaponry should have been stored in the Ministry of War’s armory; yet here it was, in a merchant’s salt field.