The mass production of the Imperial Axles had turned the Iron Works into a high-pressure conduit of metal, but that conduit terminated at the edge of the northern marsh. To fulfill the Imperial contract, Kael had to move the fifty-unit shipments across the Sinking Trestle—the three-hundred-yard timber span that bridged the most unstable section of the Iron Road. Under the weight of the standard ore wagons, the trestle had held, but the new "Axle Trains" were different. Each crate of fifty axles, combined with the weight of the reinforced iron-rimmed wagons, exerted a static pressure that pushed the pitch-treated timber piles to their absolute mechanical limit.
Kael stood at the edge of the marsh, his boots sinking into the freezing, sulfurous muck. He watched as a test wagon, loaded with only twenty axles, rolled onto the span. The groaning of the timber was not the usual rhythmic creak of a healthy structure; it was the sharp, intermittent crack of fibers snapping under tension. Through his optics, Kael could see the central piles bowing outward, the "Sinking Trestle" finally living up to its name as it began to subside into the bedrock-less silt.
"The pile depth was calculated for four tons," Kael noted, his voice flat against the wind. "The axle shipments are pushing us to six. We aren't just crossing the marsh; we are driving the bridge into it."
The grit of the situation was the lack of time. The Imperial deadline was a fixed variable, and the first shipment had to move within forty-eight hours. Kael couldn't rebuild the bridge from stone, and he couldn't wait for the ground to freeze harder. He had to engineer a solution that utilized the materials he had on-site: iron, fireclay, and the raw muscle of the Tier 0 labor pool.
He initiated the Lateral Reinforcement Protocol. Instead of trying to stop the vertical sinking, Kael decided to distribute the load across a wider surface area using "Floating Pontoons." He ordered the production of large, airtight iron cylinders at the forge—effectively oversized barrels—which were then bolted to the sides of the primary timber piles at the water line. These cylinders, filled with air, would provide a measured amount of buoyancy, counteracting the downward force of the heavy wagons.
The work was a nightmare of cold and filth. The laborers, led by the former mercenaries who were now the barony's unofficial "Heavy Engineering" squad, had to dive into the freezing marsh water to secure the bolts and seals. The "grit" was literal: the peat-stained water blinded them, and the jagged edges of the iron cylinders tore through their protective leather gear. Kael was in the water with them, using a hand-held iron "Sounding Rod" to feel for the vibration of the piles as the pontoons were pressurized.
"The iron isn't enough," Hektor shouted from the bank, his breath a thick fog. "The silt is too soft. Even with the buoyancy, the lateral sway will snap the rails when the train moves."
Kael's secondary solution was the Tensioned Iron Web. He utilized the failed, "No-Go" axles from the assembly line as anchor points. He had them driven deep into the stable ground on either side of the marsh, then connected them to the trestle's primary beams using long, hand-forged iron cables. By tightening these cables with a series of heavy turnbuckles, Kael created a pre-stressed structure that pulled the bridge together from the sides, negating the outward bow of the piles.
Socially, the "Trestle Crisis" became the ultimate test for the Aspirants. The work was so dangerous and miserable that the productivity bonuses were no longer enough to maintain morale. For the first time, Kael had to rely on the "Old Citizens" to provide more than just technical foremanship. He saw the original survivors—the men who had lived through the siege—wading into the water to help the newcomers. The shared physical misery of the marsh acted as a final solvent, dissolving the last of the elitist barriers. They weren't "Old" or "New" in the muck; they were simply the men trying to keep the bridge from collapsing.
On the morning of the shipment, the first full Axle Train—fifty Imperial Axles, crated and strapped—crept onto the reinforced trestle. The sound was a complex symphony of industrial stress: the hiss of the buoyancy tanks settling into the water, the singing of the tensioned iron cables, and the deep, low thrum of the timber piles. Kael stood at the center of the span, his hand on the primary rail, feeling the vibration.
The bridge subsided four inches under the weight, but the "Floating Pontoons" held the line. The tensioned cables vibrated like the strings of a massive, dissonant instrument, but the lateral sway was contained. The train crossed the three hundred yards in six minutes—the most expensive six minutes in the barony's history.
The Axle Train reached the solid ground of the southern road. The fifty axles were on their way to the capital. Kael looked back at the Sinking Trestle. It was a scarred, ugly patch-job of iron and wood, but it had held. The "Trestle Strain" had been overcome, not through elegant design, but through the aggressive, high-pressure application of engineering in the mud.
"Log the deflection," Kael told Elms, who was already recording the data. "We have three more shipments to move before the frost breaks. I want the buoyancy tanks checked for leaks every six hours. The bridge stays alive until the debt is paid."