Qin is surrounded by the sea, edible sea salt, after hundreds of years of development and purification technology has made great progress, and Song Yunhe since the successful firing of activated carbon, the filtration program has changed a lot, even if the whole country has not eaten refined salt, but the palace and princess mansion and even the powerful families in the capital have long begun to use pure salt like snowflakes.

Before Song Yunhe left the Qin Kingdom, he brought a lot of excellent snowflake salt, and the food and drink along the way and the current eating and drinking in the Song Mansion were all self-brought salts, so he had not been able to find the difference with Kyushu.

Chai Yu has not set foot in the Qin State for a year, and the correspondence with Song Yunhe has been cut off for nearly half a year, and the matter of refined salt has not yet been known.

The color is white but not transparent, and the crystal particles are much larger than the sea salt of the Qin Kingdom, and the mouth is rough and bitter. It is very different from Song Yunhe's salt.

"Is this the best salt for the next week?" asked Song Yunhe.

"Hmm. Chai Yu nodded, the next week is mostly mined mountain salt and well salt, and there is still a limit on the amount of bitter salt that the people can buy, and the loose salt is a special supply for the powerful.

"Didn't you feel that the taste was different from yours when you ate with me earlier?" Song Yunhe was puzzled, although her taste was now a little more sensitive, but the taste of the two was so different, and it was impossible not to feel it for a few days on the road, "Is there a problem with your sense of taste?"

"I have no problem with my sense of taste. Chai Yu replied with a smile, he had already discovered that Song Yunhe's food taste was different, delicate and exquisite, but because he was used to her always making things different from the world, he didn't ask or guess where the difference came from.

But now her question pulled him back into his normal thinking, and asked, "So, the flavoring agents used in your meals are all derived from here?"

"Of course!" The oil, salt, sauce and vinegar of the interstellar era is also something that Song Yunhe has only heard of in his life, and he can't buy and can't afford it, and what makes her even more puzzled is, "What are you buying when you have traded with Changzhen in the past few years?"

Chai Yu was a little speechless, not to mention how many taels of silver he had sold the food and arms he needed most in recent years by Song Changzhen, salt has always been an important weapon of the country, and its impact on an era is not at all as heavy as the original popping beads, so it is impossible for Song Changzhen to rush to launch a deal before the Qin State is strong.

Song Yunhe didn't really think of a definite answer, and she also understood that this kind of political transaction would not be just a matter of money and silver, so she asked again: "Can I take this jar of salt home and study it?"

Chai Yu nodded.

So Song Yunhe returned to the Song Mansion early on the first day of entering the palace, dissolved the salt he got back in water and analyzed the composition, and then carried out activated carbon filtration and physical purification, although there will still be some impurities, but compared with the original coarse salt, it is already a world away. However, how this kind of improvement should be combined with the salt-making process in the coming week is obviously not something that Song Yunhe can think of at home.

Chai Yu took her to Yunjing for only ten days, and it was impossible to let her go again.

Song Yunhe thought about it for a few days, so she asked Lingque to add an extra one when she delivered the meal, and she asked Chai Yu to invite Mr. Xun Zhang to eat together.

The old gentleman's eyes lit up at the first bowl of soup, but he quickly finished the rest of the dishes with a calm expression, and left without asking any more questions.

This has been the case for several days, Song Yunhe had to find an opportunity to take the initiative to open his mouth after the officials who went to school left, "Mr. asked me what kind of skills I have a few days ago, but I don't know the same, I'm really ashamed to think about it." So, I've learned some tricks these days, so why don't you bother to take a look?"

Mr. Xun Zhang seemed to be very tired after the lecture, sat at the desk and drank tea, then raised his eyes to look at her and asked, "Why do you want to take out the ugly tricks when you know that it is a small skill?"

Song Yunhe's tongue is knotted, don't all the literati speak so humbly!

Mr. Xun Zhang didn't wait for her to answer, and said: "There are many people in the world who don't understand the ten arts, if they have to find a way to make up for their shortcomings, most of them will starve to death if they don't get tired to death." Do you want this kind of atmosphere after the next week?"

Song Yunhe shook his head.

"Then do you have something to say?" Mr. Xun Zhang lowered his eyes and took another sip of tea.

"Hmm. Song Yunhe responded, his heart was already bright, "The day before yesterday, the students and His Majesty had dinner and found that the salt used was very different from what Qin Guozhi saw. ”

"You can show the old man. ”

The dissolving and filtering things have long been placed in Chai Yu's south study, Chai Yu naturally witnessed the whole process with Mr. Xun Zhang, Song Yunhe explained each step carefully as if teaching the students, both of them are knowledgeable people, and the knowledge of physics is easy to understand.

"As far as the old man knows, the salt production from brine is to lead it into the filter soil, and its meaning should be the same as your move, so the key difference is what you call 'activated carbon', which is easy to obtain?"

"There is a certain degree of difficulty, but fortunately, Qin already has a complete firing technology, which can be replicated and promoted in the future. "Being able to implement charcoal burning technology in the coming week is a great thing for Song Yunhe.

"Is the firing method also from your hand?" asked Mr. Xun Zhang, but his eyes were already determined.

Song Yunhe looked at Chai Yu next to him embarrassedly, and when he saw him smiling back, he nodded and admitted it, but he really didn't want to show off his skills at all.

"That's not like we're stealing. Mr. Xun Zhang nodded and said: "Although this method can purify the salt, the brine mining in the coming week is limited, and I can only sigh with admiration." ”

"Is it difficult to mine brine?" Song Yunhe really didn't know about well salt, it sounded much more difficult than sea salt, and looked at Chai Yu and asked, "Otherwise, I can go to the brine mining site to have a look?"

Chai Yu didn't immediately refuse, but there was disapproval in his eyes, Mr. Xun Zhang didn't interject and found an excuse to leave, Song Yunhe looked back at him and was still eager to try, but Chai Yu stretched out his hand and covered it lightly, and said helplessly: "Ah He, I didn't let you come to me to be a coolie." ”

"But I'm here to help you. Song Yunhe hugged his waist with both hands, his little head rested on his chest, and his words were light and playful, "But you said that you want to get along with me, but you only let you spit bubbles by yourself, how can you?"

Chai Yu looked at the girl in her arms, smiling smartly, her eyes were like the Milky Way flickering, and the seductive people's hearts were numb, she lowered her head and kissed her soft green silk, but she suddenly raised her head, and her delicate warm lips were attached to the corners of his mouth.

Time seems to stand still, but there is a faint fragrance in the air, Chai Yu slightly tilted her head to kiss her petal-like pink lips after the rain, the breath is full of hooked people's indulgent breath, and the blend of lips and teeth seems to be intoxicating confusion.

Song Yunhe's heart seemed to be wrapped in fine silk little by little, gentle and throbbing, the fingers of the hands holding Chai Yu were slightly bent, and the bones seemed to be through microelectricity, crispy and numb, and there was some kind of longing mixed with indescribable.

Chai Yu's movements suddenly became a little heavier, the tip of her tongue hurt from biting, and when she came back to her senses, her chest rose and fell, but her wet eyes were confused.

"But do you still think that foaming at each other is spitting bubbles?" Chai Yu asked with a low chuckle.

"You, you," Song Yunhe opened his mouth, but his brain was as chaotic as a long-term lack of oxygen, and he couldn't find the words to say for a while.

Chai Yu laughed out loud as if she was extremely happy, touched her head to appease, and said softly: "My Royal Highness the princess is now grown up, but she has not yet learned the separation technique." ”

Song Yunhe was inexplicable.

"There is no news about the silver mine yet, how can you go to make salt again? Moreover, there is news from the Li family that Li Zi will arrive in Yunjing in a few days. How about we wait for him to arrive?"

"Is there any news from Li Ziqi, have you written to me?" Song Yunhe was instantly diverted.

"I haven't written to you, it's the head of the Li family who wrote that he has done something amazing, and he will send it to Yunjing to show me in the near future. Chai Yu looked very expectant, "You don't want to see his achievements? ”

"What credit can I have, 'the master leads the door and cultivates in the individual', he was already extremely good in his childhood. Song Yunhe was modest, but his flushed face was abnormally radiant, and he was always willing to make achievements for his students. "I haven't seen him for a year, but I should have seen him first, right? ”

Chai Yu nodded in agreement.

Song Yunhe decided to temporarily suppress the matter of salt mining, and went back early after waiting for Chai Yu to have dinner, if the plum period was really coming, she wanted to arrange for the children outside to go back to the Song Mansion to get together, and she also had to meet to confirm the progress of the prospecting.

How poor this land has been for so long, and nothing of value has been found.

Chai Yu directly took her hand and entered the tunnel and returned to the Song Mansion.

"Don't you have anything to do today?" Song Yunhe was curious, Chai Yu had never returned so early for so long.

"I want to accompany you, lest Her Royal Highness always think of going elsewhere. Chai Yu carefully helped her down the steps, and there was a rare banter in her tone.

Song Yunhe snorted lightly, "We are not married yet, you have to take care of where I go, won't you tie me up in the future?"

"If Her Royal Highness can turn herself into a kitten, I will keep it in the hem of my coat every day. ”

Song Yunhe's hands were inexplicably wet, his face was faintly hot, but he couldn't see the red powder clearly in the authentic pearl light, and pretended to be cold: "If I can turn into a cat, I will definitely turn you into a mouse first." ”

Chai Yu chuckled, holding her hand a little tighter, and Song Yunhe also laughed in a low voice.

The two of them seemed to have never gotten along so comfortably for a long time, and walked slowly for a long time with their hands clasped together before they met Qiang Wu, who drove to pick up people, and then got in the car and went back to Song Mansion together.

Xu is looking at Chai Yu's return, his Royal Highness is bright, the dinner made by the sparrow is a little richer than usual, except for a few dishes that Song Yunhe likes, the others are all according to Chai Yu's heavy tone, although there is not a little left, but they also eat a lot.

The two of them took a walk in the backyard to eat, and then Song Yunhe was extremely sleepy, and Chai Yu fell asleep before she returned to her residence.

There are no white clouds in the blue sky, the moon is bright and the stars are scarce, the white moonlight spreads into half of the attic, Chai Yu sits in front of the bed and looks at the sleeping girl quietly, her face is calm.