Chapter 332: Small metal pelletsWithin the Green Sparrow tribe's courtyard space, Hei Wa was digging a hole.
Han Cheng was nearby, using the soil dug up by Hei Wa to mix with water and mud.
They were planning to rebuild a kiln or a forge here.
The earthen kiln by the river outside the Green Sparrow tribe was suitable for firing pottery and tiles, but it was too large for charcoal fire to smelt iron.
Digging soil, stacking ventilation holes... everything went smoothly. In half a day, a brand new small furnace was built.
Flames burned brightly Inside the furnace, and the ventilation was excellent.
It had to be said that Hei Wa's skills in building these things were improving.
Han Cheng walked to the side of the stone slab and picked up a few lumps of mud, which were only half dry.
After some thought, he brought over a dozen of them and placed them by the edge of the furnace to dry faster with the heat.After a while, when the lumps of mud were almost dry, Han Cheng placed the charcoal that had been burned previously into the furnace.On top of the charcoal were four lumps of mud.
Just as the experiment of smelting iron had begun, Han Cheng encountered a problem.
The fire in the furnace wasn't burning vigorously enough.
The solution was to get a small bellows or a blower.
Han Cheng was familiar with bellows. When the weather turned cold during his childhood, people would come to the village to make popcorn.
They set up a simple stove, lit a fire inside, and placed something that looked like a burnt and blackened bomb on top.
Inside were corn or rice.
After burning for a while, this "bomb" was removed from the fire, stuffed into a long pocket, and stomped on. After a loud bang, the warm popcorn was born.
What Han Cheng liked to do the most at that time wasn't picking up the fallen popcorn with other playmates but squatting beside the stove and operating the bellows, also called a "wind gulu."
This device was relatively simple in structure. It mainly used the wind generated by rotating fan blades to blow into the narrow outlet and then into the furnace.
Seeing hope, one would be full of enthusiasm.
Han Cheng couldn't make complicated bellows, but a simple one was no problem.
Without iron sheets to make the outer shell, he used clay to sculpt a model, baked it dry, and then fired it into pottery.
Without iron rods for the axle or iron pieces for the fan blades, he used wooden sticks and bark instead.
He carved a cross-shaped aperture at one end of a wooden stick with a stone knife and then overlapped two pieces of bark, each measuring ten centimeters long and four centimeters wide, at the cross point.
A two-centimeter notch was carved at each intersection, and then they were wedged onto the wooden stick.
After tying them with thin ropes, a shaft with fan blades was made.
When pressed with the hand, a wind would come out when placed inside the clay shell, with a stone with small pits underneath.
A pre-made clay pot was placed on the outlet, and the other end was inserted into the furnace's air inlet. With a few presses, the wind entered the furnace through the clay pipe, and the fire inside became stronger.
Hei Wa's eyes lit up instantly.
After operating for a while, his hands hurt, so Han Cheng found a hand drill, removed the drill rod, and installed the shaft with fan blades. A few presses back and forth became effortless.
One thing to mention was that ordinary bellows were placed upright, but the type made by Han Cheng was placed flat so that it could be used for wind pressure ignition with a hand drill.
"Whoosh, whoosh..."
Hei Wa pressed the hand drill, watching the flames inside the furnace rise and fall with his movements, his eyes bright.
Just like, when Han Cheng used to squat beside the popcorn stove, shaking the bellows, having the bellows now would speed up the smelting process of these iron-containing lumps of clay.
The iron-rich clay lumps in the furnace turned red in less than half an hour.
After further heating, there were signs of melting and softening.
When the temperature seemed right, Han Cheng used two long sticks to extract them from the furnace and placed them on a nearby stone prepared in advance. He extinguished the fire on the two sticks used for ignition and picked up another large stick to start forging while the iron was hot.
"Bang, bang, bang!"
With each strike, the red slag flashed and rolled aside.
Before long, the lump of iron-rich clay turned from red to black.
After a while of forging, Han Cheng stopped when he couldn't continue.
At this point, the lump of iron-rich clay had lost almost half of its original size.
After soaking the lump in water and lifting it out, Han Cheng carefully examined it in his hand and found that this irregular piece was still far from resembling iron.
After some thought, Han Cheng found a stone and smashed the incomplete piece of "iron" open. Upon closer inspection, he found the shadow of tiny iron beads inside.
Looking at the eight beads in his hand, each no bigger than a green bean, Han Cheng couldn't help but smile.
Iron!
This was iron!
Having been in this era for four years, he finally saw metal traces. How could Han Cheng not be excited?
Looking at Han Cheng, whose smile almost reached his ears as he held the small lumps in his hand, Hei Wa, nearby, couldn't understand why the Divine Child was so happy over such unremarkable things.
Could this tiny thing be used to make stronger and more durable tools than stones?
But soon, Hei Wa also laughed, not because he understood what was going on, but because he was following the Divine Child's foolish joy.
"Burn! Keep burning!"
Han Cheng cherished these tiny iron beads in his hand and excitedly shouted like he was on fire, throwing dozens of clay lumps into the furnace at once...
From this day on, the newly built furnace in the Green Sparrow tribe burned continuously for five days before finally stopping temporarily.
"Splash, splash..."
Han Cheng held the not-too-large but somewhat heavy jar, shaking it occasionally with a foolish smile.
Inside were iron beads of various sizes, the results of continuous labor over the past few days, weighing about 1.2 kg.
This was all the iron-rich clay they scavenged near the Green Sparrow tribe.
Han Cheng became more confident about what lay ahead with these iron beads.
The next step with these high-purity iron beads was to heat and melt them to forge them into blocks of iron.
After much thought, Han Cheng's method involved laying a layer of charcoal in the furnace and placing the iron beads in four different-sized clay bowls on top of the charcoal.
Then, a thick layer of charcoal was added on top, and the fire was lit.
This crude method and tool consumed a lot of charcoal and time.
However, now was not the time to consider such things. Obtaining iron was already a blessing from heaven. Who had time to consider about those things?