"This is a perfect, ready-made 'Dry Distillation Kiln'!"

"It is a metal container that can isolate wood from flames, allowing for oxygen-deprived heating, and its capacity is just right for my small-scale production."

He tightly packed the small iron barrel with dry birch blocks he had prepared earlier, filling this approximately 20-liter iron barrel with nearly ten kilograms of dry birch wood.

Lin Yu'an quickly calculated in his mind that according to the most primitive dry distillation method, achieving a charcoal yield of twenty percent would be a success. This barrel could produce at most less than two kilograms of charcoal.

He frowned slightly: "Forging that thick steel rod is a huge energy-consuming process, and each heating requires a large amount of charcoal."

"But if it's only two kilograms, it will probably only be enough for a few critical heatings and hammerings. This means I have no room for error."

"However, luckily..."

As he spoke, he walked into the shelter and dragged out a bundle of charcoal tied with nylon rope from the corner, pouring it onto the ground.

"Clatter—"

A pile of irregularly shaped black charcoal fragments rolled out, weighing about five or six pounds.

He picked up a piece of charcoal and explained to the camera: "Since the first day I built this fireplace, I have been accumulating these things."

"When the logs in the fireplace pile and burn, the central wood cannot burn completely due to lack of oxygen, forming this kind of incompletely carbonized charcoal."

He broke a piece of charcoal forcefully, revealing its cross-section with some remaining wood fibers inside: "Look, its degree of carbonization is not as high as professionally made charcoal, its calorific value might be slightly lower, and it may produce some smoke when burned."

"But as a basic fuel, or when mixed with high-quality charcoal, it is completely sufficient."

"This over six pounds of charcoal, along with another box of high-quality refined charcoal I plan to make, will together provide nearly five kilograms of fuel. This will greatly increase my margin for error."

"Now, I just need to make one more batch to replenish the high-quality refined charcoal, and by tonight, all the preparations will be complete. Tomorrow will be the official forging day!"

He found a soapstone slab of suitable size, placed it tightly over the opening of the iron barrel, and then used "adobe mud" to seal all the gaps between the slab and the barrel.

Leaving only some tiny exhaust holes poked out with tree sticks in the adobe mud to expel wood gas.

Then, he quickly built a simple firepit with a few stones beside the forge and ignited a roaring bonfire.

He placed the "Dry Distillation Tank" filled with wood firmly across the firepit.

The flames rose greedily upward, rapidly heating the iron box. This self-operating "carbonization project" would, over the next few hours, produce the most critical "black gold" for him.

And during the long waiting time for the fuel to emerge, he could focus on another equally complex task.

If charcoal was the "blood" needed for the upcoming forging, then the bellows would be the "heart" driving this blood to surge.

He dragged the orange-colored [Fishery Floating Box] to the center of the shelter.

This was an extremely heavy thing, dragging two deep grooves through the snow.

He walked around the box, carefully observing every detail, and a bold and ingenious design blueprint began to form in his mind.

He decided to use a horizontal push-pull bellows design.

At the bottom edge of one corner of the box was a small broken hole, where he planned to utilize the existing hole, expanding it to transform it into the main air outlet.

He took out the [steel draw bar bolt], heated one end red-hot in the fireplace, and then, like a branding iron, began enlarging the small hole.

The scorching steel rod contacted the cold HDPE plastic with a "hissing" sound, emitting pungent white smoke.

He patiently softened and scraped off the hole's edge bit by bit until it was just the right size to accommodate the piece of PVC pipe he had picked up earlier.

He inserted one end of the pipe into the box, then packed all the gaps between the pipe and the wall with a large amount of fine nylon threads from dismantled fishing nets, before pouring melted pine resin over it.

The pine resin seeped into the nylon fibers, cooling to form a composite sealing material akin to fiberglass.

Next was the core component of the entire project, the piston and top cover.

He selected a rectangular wooden board from his reserve driftwood, slightly smaller than the internal cross-section of the box, to serve as the piston head.

He then found a straight birch wood, sharpening one end to serve as the piston rod.

He had no nails, but he had a more primitive and even sturdier method.

Using a bow drill, he drilled several corresponding small holes in the center of the piston head and the end of the piston rod.

Then he threaded the piston rod through the holes, wedging it firmly at the bottom with a cross-shaped wooden wedge.

In the next step, he brought out the nylon rope he had soaked earlier, starting to bind it. Once dry, the rope would shrink drastically, locking the piston rod and head tightly together, even stronger than ordinary nails.

Then for the seal rings, Lin Yu'an retrieved two complete rabbit skins from his hunting efforts; they were soft, dense, and flexible — perfect materials for making seal rings.