Back at the thatched cottage, except for the night watch guards, everyone else had returned to their rooms to rest. The corner towers surrounding the cottage were all lit up with lanterns.

  Especially the corner tower near the riverbank was built high and steep, with a column on top of the top floor, four walls transparent, and a large oil lamp as big as an iron pot. The three-strand wick, as thick as a baby's arm, was also lit up, covered with a glass shade to block the wind. From afar, it shone brightly like a moon hanging from the corner tower.

  If there is an ambush nearby or a night boat approaches the shore, the lamp holder on the corner tower will also use a large bronze mirror with a concave surface to concentrate the light and project it further.

  Standing in front of the thatched cottage, Liu Yue'er awkwardly pulled out her hand and asked Lin Fu: "Are you hungry? I've made some tangyuan (sweet glutinous rice balls), would you like to have some?"

  "Hmm." Lin Xie nodded and looked at the lamp on the corner tower in the distance, shining brightly like a moon.

  This corner tower lantern was originally the idea of Ge Fu, the father of Ge Ciyu, a former official in charge of Jiangning's Ministry of Works. When he drew out the design, Lin Xiang immediately thought that if there were to be lighthouses in this world, they should look like this.

  After talking to Ge Fu, I realized that in the coastal ports and some treacherous straits of Dongming and Liangguang, there were merchants or fishermen who collectively built lighthouses. Those who couldn't afford lamp oil would accumulate firewood and burn it, but the actual light intensity and distance were limited, so the role of lighthouses in navigation at night was not obvious, which is why lighthouses existed relatively early but did not become widespread.

  Ge Fu made some improvements on the existing lighthouse foundation, and the giant oil lamp structure was similar to Lin Xue's memory of kerosene lamps. The oil lamp holder was copper-made, and the windproof lampshade was a glass cover. On one side, a large bronze mirror was used to reflect light, increasing the directional illumination intensity and distance. However, the initial design that Ge Fu showed Lin Xue had a flat bronze mirror, but Lin Xue suggested replacing it with a concave bronze mirror and specially made a wooden frame for the concave bronze mirror that could be moved and adjusted in angle.

  When the master craftsmen already knew that concave mirrors have a focusing effect, Lin's words were slightly transparent, and Ge Fu exclaimed in admiration, thinking that Lin's small improvement was wonderful. He also said that Lin would definitely be a top-notch craftsman if he joined his studio, and regretted not being able to persuade Lin to join him. Lin felt ashamed in his heart, and together with the two of them, they managed to come up with a relatively perfect lighthouse plan.

  The glaziers of Jiangning's Ministry of Works can make glass as transparent as crystal, but the cost is too high. The lanterns used in the lighthouse are a favor to Cong Ge Fu and his son Ge Si Yu. The glaziers' workshop in Jiangning also received 120 taels of silver from Ji Yun Society, enough to buy 15 mu of good land in Jiangning. The concave bronze mirror was made by several master craftsmen from Jiangning who spent nearly a month polishing it purely based on experience, and it cost 30 taels of silver. This is secondary, to maintain a certain brightness, they use multi-strand lamp wicks that absorb oil better, which naturally consumes more lamp oil. The lamp oil used in this world is not distinguished from edible oil and is slightly more expensive than pork, and the giant oil lamp in this corner tower burns one or two taels of silver worth of oil every night, equivalent to hiring 40 or 50 strong laborers.

  Limited by the light source and reflective materials, the lighthouse's farthest illumination distance was naturally far from comparable to that of later searchlights, but it could barely illuminate the distant prison island dock, with a light illumination distance of about 500 steps, which was already satisfactory in those days.

  The corner tower's lanterns not only improved the safety of the camp, but also made it possible for work to be carried out at night on the embankment. As Jiyun Society had limited financial resources and could only build a dock on the riverbank, the construction area was limited and labor force could not be increased indefinitely. The shift work greatly improved efficiency.

  Looking at the corner tower lamp in the distance, Lin Xie knew that this silver was worth spending: not only is it useful now, but also after the dock warehouse is built. The lighthouse can guide the navigation of night boats and lead them into the harbor; provide nighttime lighting for the dock, making it possible to load and unload cargo without interruption day and night, improving the efficiency of berth usage; it can also prevent river bandits from launching a surprise attack at night; although the effective illumination distance is limited, but even in the north shore of Chao Tian Tang, you can still clearly see the corner tower lamp on this side of the riverbank, which can be used as a signal lighthouse at critical moments.

  Lin tied back to the house, Liu Yue'er had already helped him light up the copper seat oil lamp in the house before cooking the tangyuan. The oil lamp was burning bean oil, and the room was filled with a faint scent of oil.

  This copper lamp was also made by the old craftsman Ge Fu, with a ring-shaped copper shade that can be opened and closed at an angle. The copper shade can block the wind, and the inner side is polished to increase the directional lighting. There is also a fine copper tube that guides the smoke generated from burning back into the water pan under the base. This copper lamp costs six catties and four taels of copper, not counting labor, and another tael of silver must be paid, so it's not something an ordinary family can afford. However, compared to using a copper-based glass oil lamp, it is much more economical and practical. Lin Xian held the slightly warm copper oil lamp in his hand, thinking: The wisdom of the craftsmen of this world should not be underestimated by later generations.

  "What are you thinking about?" Liu Yu'er brought over the cooked tangyuan, and Lin Xian'er was holding a copper oil lamp in a daze, curiously asking.

  "The intelligence of the people at that time is truly admirable." Lin tied the copper oil lamp on the case.

  "It's inexplicable feelings, when was there no fool or clever person?" Yueliang'er smiled and took the tray to leave.

  "Talk with me." Lin Xie yelled at her.

  "......" Liuyue'er hesitated for a moment, her face flushing as she said, "You really can't bully people." She sat down across from Lin Xie, propping herself up on the desk.

  Lin Xuan looked at Liu Yue'er's face, which was as red as a lantern under the lamp, and his heart skipped a beat. If she hadn't said that, he would have continued to chat with her seriously; but hearing her say that, he immediately took her soft and delicate hand and placed it in his palm, gently stroking it, feeling the tenderness that could captivate one's soul.

  Liu Yue'er was indeed embarrassed, unable to withdraw her hand, and instead placed it on the table, resting her cheek on her arm, gazing up at Lin Xie under the lamp. She felt a sweetness in her heart, but also feared that Lin Xie would make further demands. On one hand, although she had been sent back to her natal home, her husband's family in Shiliang County still held some power, and if the Xiao family were to cause trouble, it could lead to big problems. In this era, a widow remarrying required the consent of her late husband's family; otherwise, she would be accused of adultery like some female prisoners on the island. On the other hand, having maintained her chastity all these years, Liu Yue'er naturally wouldn't demean herself. If Lin Xie were to give her an official status, she had already thought about it and wouldn't mind being a concubine. However, things couldn't remain ambiguous forever. The problem was that Lin Xie had been busy with the prison island and river mouth these past few days, leaving him no time to think about other matters. Moreover, Liu Yue'er herself couldn't take the initiative to propose or hint at anything, feeling that it would demean her.

  "Come sit over here..." Lin Xuan looked at Liu Yue'er's face, which was bowed down on the table, and it looked exceptionally delicate and beautiful. Her translucent skin was slightly flushed, looking like it might break if touched. Her hair was as black as a crow, her ears, nose, and lips were all perfectly shaped, and her long eyelashes sparkled in the lamplight, making every feature of hers stunningly beautiful. It's said that a beauty is the most intoxicating wine, and just gazing at her made him feel slightly drunk. Lin Xuan didn't take advantage of the dim room, not because he couldn't help himself, but he pulled Liu Yue'er's hand, wanting her to sit in his lap.

  "...Liu Yue'er's eyes were clear and bright like a spring, her gaze flowed with a gentle movement, but she lightly thought of pulling back, her mouth softly saying, "Yue'er should go back to rest." At this late hour when the moon was hanging alone in the sky, she actually wanted to hold Lin Xuan in her arms, yet she was also afraid that if she indulged him, she wouldn't be able to control him.

  Lin Xie could read the desire to welcome and refuse in Liu Yue'er's eyes, and he also understood the fear of women in this world when their chastity was exposed to outsiders. The passion and impulse that brought temporary pleasure would make women fall into extreme anxiety and fear of pregnancy for the next month. Lin Xie wouldn't do such a thing, and he was afraid that explaining the concept of safe period to Liu Yue'er at this time would be useless. He grasped her hand and said: "I also see the situation of the female prisoners on the island; I won't harm you, it's just that I can't leave now to go to Shiliang..."

  The female prisoners detained on the island, eight or nine out of ten were imprisoned for adultery. The former prison guards and bookkeepers forced the female prisoners to sell their bodies in brothels in Quyang Town. In later generations, this was considered a heinous crime that would be despised by all, but at the time it was considered a light offense that could be redeemed with copper cash. Many people even came forward to defend them, including Chen Xiyi, a great scholar of the time, who openly declared that women who committed adultery should be sent to brothels to redeem their sins. This shows the attitude of the people towards women who lost their chastity and committed adultery. In some places in Chongzhou County, local villagers even collectively raised funds to build a "Temple of Righteousness" where widows were concentrated and imprisoned to prevent them from losing their chastity.

  Listening to Lin Xie say that, Liu Yue'er still didn't feel at ease and softly said: "You really can't harm me..." Her face flushing red, she sat down beside Lin Xie, who took advantage of the situation to pull her into his arms. Liu Yue'er's hands were propped against Lin Xie's sturdy chest, but she struggled a bit, only to find herself sitting on something hard and wooden like a root, her powdered face as red as if drunk, instantly quieting down and burying her head in Lin Xie's embrace, no longer struggling or saying anything.

  After the spring night of Jingzhe, the weather was no longer cold, and I had changed into a spring shirt. Holding the beauty in my arms, I could clearly feel the softness and warmth of her body. Lin Xie was still a young man at that time, but he wasn't ignorant of the affairs between men and women. Looking at Liu Yue'er's face, which showed shyness and budding desire, he felt even more enchanted by the beauty in his arms. His face pressed against her smooth hair, he savored the rare tenderness of this deep night, just like a spring stream flowing quietly under the moonlight. The stirring desire was not an uncontrollable beast.

  Liu Yue'er felt a lump in her throat as she sat on Lin Xie's lap, her face burning with shame and her heart racing. But after a while, when the overwhelming emotions subsided, she felt a sweet and soothing comfort that made her put aside her worries about losing her reputation. She lifted her head from Lin Xie's chest and looked into his eyes, saying: "You haven't eaten your tangyuan yet..." She picked up the ceramic bowl and used a spoon to feed Lin Xie the sparkling tangyuan, and he let her eat too, so she ate two of them as well.

  In the second half of the night, the moon in the sky was covered by clouds, but the lamp on the corner tower still hung like a full moon above the treetops, shining through the window. Liu Yu'er sat in Lin Xiu's arms and whispered: "That corner tower lamp is really good, poor families can't afford to burn lamp oil at night for work or reading..."

  Lin Xian thought: One or two lamp oils are equivalent to more than half a catty of rice, which is really not something that ordinary families can afford to use.

  **************

  P.S: Looking for red envelopes.