Pottery Firing Failure

The air-dried pottery blanks sat silently in a corner for several days. Their color grew deeper, and their texture became harder.

They were no longer as fragile and easily damaged as when they had first been shaped. Tapping them with his fingertips produced a dull, solid "puff puff" sound, indicating that their internal structures had begun to stabilize.

Chen An stared at the two crooked but basically formed vessels—the shallow bowl with its lopsided rim and the wide-mouthed jar with its distorted proportions. A nearly ceremonial sense of anticipation and tension stirred within him.

Firing was the final step in a clay vessel's rebirth, as well as the most crucial and riskiest step, one filled with the unknown.

Its success or failure would determine whether the fruits of his clumsy work over the past several days could truly become usable vessels. It would also determine whether his simple wish to "improve his life" could take a solid step forward.

He knew full well that primitive open-air bonfire firing had an extremely low success rate, and that the finished products were often riddled with flaws.

But he had no other choice for now. Building a pottery kiln capable of controlling the temperature required more complicated planning and far more materials. It was far beyond something he could accomplish in a single day.

He decided to try firing them in a bonfire first, treating it as a "preheating" test for the pottery blanks and a practical lesson in the firing process.

On one side of the courtyard, near the kitchen stove, he cleared a small patch of level ground.

Using stones and tamped clay, he built a low, platform-like earthen stand to serve as the "kiln bed" for the pottery blanks. He tried to make its surface as level as possible, then carefully smoothed it with wet clay to reduce the risk of the pottery sticking to the platform.

Behind the earthen stand, he used the courtyard wall and several large stones to create a simple barrier, forming a semi-enclosed space. He hoped to gather the heat as much as possible and reduce heat loss.

He carefully placed the two air-dried pottery blanks on the stand, with the bowl facing downward and the jar's mouth tilted slightly downward as well. This was to prevent residual moisture inside from evaporating too rapidly during firing and causing the walls to burst.

He began stacking fuel around and above the pottery blanks. He had carefully selected dry, slow-burning hardwood branches and split firewood, interspersed with some easily ignited dry grass and dead leaves as kindling.

He imitated the way bonfires were stacked in his memories, striving to leave gaps between the pieces of fuel so air could circulate freely and the flames could burn fully, generating sustained high temperatures.

Everything was ready. Chen An took a deep breath and used a torch to ignite the kindling.

The orange-red flames quickly licked up the dry firewood, crackling softly as clouds of white smoke rose. He stayed beside the earthen stand, continuously adding more firewood to keep the flames strong. The flames gradually rose higher, their color changing from orange-yellow to brilliant white as the temperature began climbing rapidly.

A wave of heat struck his face, baking his cheeks until they burned. Sweat constantly seeped from his forehead.

He watched the pottery blanks on the stand nervously. At first, their color deepened, and their surfaces seemed to be covered with a thin layer of sweat—the sign of moisture evaporating.

As the temperature continued to rise, he expected to see the pottery undergo a wondrous transformation—the clay body sintering, its color becoming a stable light gray or orange-yellow, and its texture hardening like stone.

However, events soon deviated from his expectations.

The signs of failure appeared.

About half an hour later, the flames reached their peak. Chen An estimated that the temperature was already quite high.

He noticed that the bowl nearest the fiercest part of the fire was beginning to change noticeably.

It was not the uniform sintering he had expected. Instead, parts of it began to swell and blister! It was as if gas inside was expanding rapidly, pushing against the already unevenly thick clay body.

A moment later, a faint crack rang out, and a hairline fracture appeared across the bowl!

Chen An's heart sank. He forced down his panic and tried to use the fire tongs to gently shift the flames, making the heat distribution more even. But it was already too late.

Under the continued heat, the bowl's fate was sealed.

The crack spread rapidly like a living thing, growing wider. Amid a succession of explosive sounds, large sections of the bowl collapsed and twisted, eventually becoming a shapeless pile of hard fragments trailing wisps of smoke. Under the scorching heat, that unfortunate bowl had been completely "killed in action."

The jar fared somewhat better, but not by much.

Because it had been placed slightly farther away, it received relatively more even heat and did not burst violently. But under the sustained high temperature, its clay body seemed to undergo drastic changes in internal stress.

After it cooled—Chen An had been forced to end the firing early and risk approaching it to rake aside the hot ash—he found that although the jar had mostly retained its shape, its surface was covered in fine intersecting cracks, like the patterns on a tortoise shell.

A light tap produced a dull, hoarse sound. It had lost the crisp, solid quality it should have possessed. The internal structure of the clay body had clearly been damaged, leaving behind a weak scrap riddled with hidden cracks.

Two pottery blanks. Two ruined pieces!

The bonfire gradually died down, leaving only ash scattered across the ground and cooling pottery shards and chunks. The air was filled with the bitter scent of plant ash and the peculiar acrid smell of earth scorched at high temperatures. Chen An stood blankly beside the ruined earthen stand, watching his hard work turn to nothing. A massive wave of disappointment and dejection, cold as seawater, instantly engulfed him.

His earlier excitement, anticipation, and effort... everything had been reduced to the two useless piles of fragments before him. He squatted down and futilely tried to piece the shattered pottery together, but all he felt was the chill at his fingertips and the helplessness in his heart.

After a long while, Chen An slowly rose to his feet. He silently cleaned up the mess, collecting the broken pottery shards and cooled ash.

He did not leave immediately. Instead, he sat beside the earthen stand and calmly reviewed the entire process, trying to identify the reasons for the failure.

* Insufficient and uneven temperature: This was the most direct cause. Even burning at full strength, the temperature of a bonfire was nowhere near the peak temperature required to fire proper pottery—usually above 800°C. More fatally, the flames were distributed extremely unevenly. The bowl near the fire overheated locally, causing it to expand and burst violently. Although the jar farther away may have reached a sufficient overall temperature, the excessive local temperature differences created tremendous internal stress, causing it to crack. A primitive bonfire could not provide a stable, even, and sustained high-temperature environment.

* Control of the oxidizing atmosphere: He realized that during the later stages of firing, a reducing atmosphere—an oxygen-deficient environment—might be needed to promote the reduction of certain components in the clay body, giving the pottery better color and texture. An open-air bonfire was completely exposed to the air, creating a thoroughly oxidizing atmosphere. This might have affected the final result, though it was not the primary cause of this failure.

* Defects in the pottery blanks themselves: The pottery blanks he had made already suffered from uneven thickness and irregular structures. This had undoubtedly intensified the concentration of stress, deformation, and cracking at high temperatures. But this was an upstream problem. Even perfect pottery blanks would have been difficult to fire successfully in a bonfire.

* Lack of temperature and heat-retention measures: Without a kiln structure, he could not effectively gather, regulate, or maintain the required high temperature for an extended period. Heat dissipated too quickly, and the temperature curve could not be precisely controlled.

"Bonfires... won't do." Chen An muttered under his breath, his voice carrying a trace of bitter realization. "I need a kiln! A pottery kiln that can be sealed, control the temperature, and continuously provide high heat!"

This thought was clearer and firmer than any before it. He understood that the birth of pottery depended not only on clay and flames, but also on a tool created by human ingenuity to control those flames—the kiln. This was the unavoidable path from primitive pottery-making to mature pottery-making.

Although his first firing had ended in complete failure, with both pottery blanks reduced to powder, Chen An had not been utterly crushed. This painful failure had revealed to him in the most direct and undeniable way the technological chasm he had to cross on the road to success: building a pottery kiln.

He rose to his feet and took one last look at the pile of cold ash and broken pottery shards. They were witnesses to his failure, but also precious lessons. They told him that he had not yet passed the test of fire, but the path to success had already begun to emerge from the ashes of failure.

His next step was no longer to practice shaping clay, but to turn toward a grander and more complex project: designing and building his first pottery kiln. It would be a more arduous challenge than making pottery itself, but for light, clean pottery and a more convenient life, he had to try.

The wind of the Primordial Wilderness swept through the Small Courtyard, carrying a hint of coolness, but it could not extinguish the flame that had been rekindled in Chen An's heart—a flame pointing toward the blueprint of a pottery kiln.

(End of Chapter Twenty-Two)