The Seed of Prosperity (10)
With molten glass successfully poured into the working tray, Yi Yeon could finally create flat, smooth glass. He immediately ordered craftsmen to begin producing mirrors. If only he had thought of it sooner, he would have swapped the translucent Hanji paper in the windows of Gangnyeongjeon and Geunjeongjeon for transparent glass. He would have loved to see the royal palace bathed in natural light.
'But that was impossible back then.' Now that glass-making was no longer a secret, it was straightforward. The specialized artisans of Seoljaegi could produce it effortlessly. Yet large sheets suitable for windows remained out of reach. The trays could be made from fire-resistant Korean earthenware, but the equipment needed to melt and transport the glass required sturdy iron. Molten glass exceeded 1,300°C—too hot and far too heavy for earthenware alone. Thus iron frames had to be fashioned, with their interiors lined in fire-resistant clay to serve as containers for glass production.
'Like a blast furnace.' The larger the sheets, the more iron would be needed. Yet there was no way to obtain such vast quantities of iron right away. 'Damn it! I need to mass-produce iron now!' Traditional methods yielded pitifully little output while demand was enormous. No matter how much advanced technology was available, without enough iron the big mirrors simply could not be made. Therefore Yi Yeon decided on smaller mirrors first. 'Wise judgment indeed.' With Seoljaegi artisans available, he realized mirrors could be sold for far more profit.
'I need them too.' Acne was not severe, but every now and then one or two large pimples would swell and nag at him. Having reached his decision, Yi Yeon summoned Chief Eunuch Hwa Gye-ju at once. In the laboratory at the palace, after verifying the prepared materials, Yi Yeon told him: "From now on I will teach you how to make glass into mirrors. Watch carefully and do not make mistakes. You could die. Do you understand?" "Yes, Your Majesty." Yi Yeon demonstrated personally while explaining. "First, dissolve pure silver in concentrated nitric acid to make a silver nitrate solution." 3Ag + 4(HNO3) → 3(AgNO3) + 2(H2O) + NO "This solution can also be used later to create forgery-proof banknotes, so neither the method nor the solution itself may be exposed." "I shall remember it, Your Majesty." Yi Yeon planned to issue paper currency once coin circulation became active. Convenient, portable coins would inevitably be hoarded. Yet infinite minting was impossible. Production costs were steep, the coins were heavy and would disrupt circulation, and copper was already in short supply for shells. Moreover, paper currency, unlike coins, could be damaged by fire—providing a real advantage. Once issued, it would return to the royal bank’s coffers. Therefore issuance was not optional; it was essential. But forgery remained a grave problem. 'I cannot let decay breed corruption!' The entire economy—and society—would collapse. To prevent that, Yi Yeon intended to use silver nitrate ink, the same anti-forgery method employed in 21st-century India. The ink would cause the printed portions to appear in intaglio relief under light, making counterfeits instantly obvious.
"Next, ferment urine or chicken dung to produce ammonia water. Coating glass with mercury or silver does not make it a mirror. It merely flows down or oxidizes, clouding and discoloring the surface. That is why even the 13th-century Venetian craftsmen could not make mirrors directly. They could produce flat glass, yet after decades of research they finally discovered the method: not applying the metal to the glass itself, but attaching a silver- or mercury-coated metal plate to the back. Such mirrors were sold in the Venetian Republic for 150,000 francs—wedding gifts for the French queen Marie de’ Medici. 'It was the size of a book,' they said. Later the vacuum-deposition method was used, but the surface soon oxidized and rendered the mirrors useless. Worse still, mercury was an extremely toxic heavy metal to the human body. Therefore Yi Yeon chose the mercury-free silvering process instead. It would be several hundred times more durable than mercury-deposited mirrors, usable anywhere, and safe. Yet silvering required ammonia water to form a uniform, smooth layer on the glass surface. Other chemicals could work, but obtaining them was harder. So Yi Yeon taught him how to produce ammonia water from urine and chicken dung. "Passing the fermented gas through water, you mean?" "Correct. Though impure, this is the best method available now. From here on you must be extremely careful. Mixing silver nitrate solution with ammonia water produces a violent reaction and invisible toxic gas. Always ventilate first and test everything. Do you understand?" "Yes, Your Majesty! I shall remember it more than once!" Hwa Gye-ju now understood that the more invisible the gas from chemical reactions, the more dangerous it was. "Finally, clean the glass surface with sodium hydroxide, then apply the prepared silvering solution. The mirror will be complete. Send the solution to Seoljaegi’s master." "Yes, Your Majesty." The Seoljaegi artisans had already made mirrors using this method, framing them in lacquered najeon and Seoljaegi for a luxurious finish. * * * Yi Yeon was certain no such mirrors existed in the world yet. 'Silver nitrate could be made, but the reaction with ammonia water and the method of application—he probably did not know them. If so, he would perish.' Thus the value of these silvered mirrors was priceless. Yi Yeon had decided the price in negotiations with the Ming envoys and trade director Sim Tong-won. 'The price is the price,' he thought, yet an undetermined figure was nothing more than hot air. So he summoned Sim Tong-won. The profits from this transaction would directly benefit the royal treasury, which in turn served the nation’s interests, so he wanted to reward him. Yet he could not. It would only make the man worse. 'If it were any other minister I would not have bothered.' Now all his officials were trying to support the young king’s reforms because they benefited themselves. They also judged right from wrong by feel and acted accordingly. But Sim Tong-won had none of that. He was nothing but a spoiled brat who only looked out for himself. Yi Yeon resolved once more to give him a firm lesson. He would not learn, but his cleverness would let him understand the situation. "Trade Director!" "Yes? N… yes?" "I once warned you to stay out of matters you have no business meddling in, and it seems you have not heeded me." "Forgive me, Your Majesty. I am old and my memory fails me." Yi Yeon smiled as if he had known this would happen. "Then let me repeat myself. I do not like those who plot behind my back. Pay heed." "I shall remember." Even now Sim Tong-won only replied. 'This is going to be difficult.' Yi Yeon prepared a shock so profound it would be etched in his mind. He took one mirror from the box. This one was framed in Seoljaegi, making it look even more valuable. Yi Yeon tossed it to the floor and said, "You know what happened to me. I lost my grandfather early. I am not a legitimate heir. Yet I became king of this country. There must be more people than I who resent it. I have heard it myself." "Your Majesty, what do you mean…?" Sim Tong-won’s voice trembled. The young king’s words frightened him. Sensing the gravity, sweat broke out on his forehead as before. "Despite hearing such words, I have taken no action until now. I laughed it off as idle talk from a gossip. But!" Yi Yeon picked up the baton lying nearby and continued. "Even after my warning, you still committed the crime. What shall I do?" "Your Majesty! Spare this old man’s life…!" Sim Tong-won fell flat on the ground. He could not have known the king was speaking of himself. "If this happens again, I will deal with you as decisively as I am now." Yi Yeon raised the baton and slammed it down on the mirror. —CLANG! Sim Tong-won was stunned and could do nothing but bow his head. Yi Yeon found the sight unbearable. 'Damn it!' He dropped the baton, stood, and said, "This warning is the last." "Yes! Yes! Your Majesty!" "Take that mirror home and hang it. It will help steady your mind when it wavers. And the mirrors in the box are gifts. Accept them." "Yes! Yes! Your Majesty…!" With those words Yi Yeon returned to Gangnyeongjeon. 'Even after this, if he still does not understand, I will have to end him.' * * * The next day Sim Tong-won arrived at Mo Hwa Gwan with an interpreter to meet the eunuchs Yao Chen and Li Qing. His face was gaunt from a sleepless night of worry. Yet he smiled brightly and greeted the eunuchs cordially. "My lords." The eunuchs nodded only slightly, their expressions full of displeasure. The two had spent enormous bribes just to become Joseon’s envoys. They knew that once they returned they could hoard the wealth. But instead of gaining anything, they had returned empty-handed. Angry, they struggled to calm themselves. They believed they could not simply be dismissed due to the importance of the alliance. Sim Tong-won read their minds and, with a strange smile, clapped his hands. A servant immediately carried in a lacquered tray and set it on the table. Pointing at the teacups, he said, "My lords, please try one. It is the Double Hua Tea favored by the Joseon queen consort." "Th-that’s so?" "Oh…!" The eunuchs paid no attention to the rich aroma of white peony, rehmannia, angelica, cnidium, cinnamon, and licorice. It was not the smell. They were captivated by the teacups themselves—white porcelain decorated with living red flowers on blue stems and leaves. "Wh-what is this?" "They do not look like white porcelain…?" Instead of answering, Sim Tong-won smiled gently and asked in a soft voice, "Do they please you?" "Mm-hmm!" "Very handsome indeed." Sim Tong-won wiped his smile and put on a sorrowful face. "Forgive me. I meant to give you gifts, but they are not to your liking?" "Mm-hmm!" "They are good, yet we have similar things." The eunuchs’ faces clearly showed their greed. They turned their heads to hide it, but their eyes remained fixed on the teacups. Sim Tong-won carefully opened the lids and offered his hand. "Then would you like to taste the Double Hua Tea popular in Joseon?" "Mm… " "Let us." As the eunuchs lifted the cups to sip, Sim Tong-won secretly dropped both lids at once. —CLINK! "Oh no!" he exclaimed in mock surprise. The lids bounced off the floor, collided, spun, and then stacked together. "Forgive me, my lords. I am old and my grip is weak… Still, they are made of Seoljaegi, so that is fortunate. Had they been ordinary, they would have shattered." The interpreter translated, but the eunuchs heard nothing. Their gazes were locked on the teacup lids lying on the floor. The clear sound they made had drawn their attention. Sim Tong-won smiled strangely and signaled the servant. Who immediately brought a full set of five teacups and a teapot in a lacquered box. The eunuchs had watched in silence the entire time, sipping the Double Hua Tea whose smooth, honey-like texture pleased their palates. Sim Tong-won unfolded the box, picked up a teacup, and lightly tapped it against the teapot. —CLINK! A fresh, crystalline sound rang out. One eunuch could not help asking, "How were they made to produce such sound?" "They were crafted in the cold winter, capturing the spirit of falling snow. That is why we call them Seoljaegi. They never break easily and give this clear, clean sound." —CLANG! "Ah…!" "Hmm…" The eunuchs’ eyes changed. Though there was nothing in the world they had not seen, these white teacups—clearly decorated with exquisite floral petals and emitting a brilliant light—were something they had never encountered before. Yet the clear sound, the unbreakable quality, the claim of containing heavenly mystery… a burning desire stirred within them. * * * Note: The teacups made of the finest real porcelain are said to produce a clear, clean sound when struck. Their high density and thin, uniform thickness create this sound. The purer the tone, the more expensive they are.