In the back yamen, Du Zhongxiao held his son, holding a small wooden stick in his hand, and taught him to blow soap bubbles. A porcelain basin in front of him was filled with blue water and a few pieces of iron pieces were inserted. Han Yueniang next to him held a few pieces of malt sugar that had been made shortly after, blew it gently, and when it was cold, she handed a piece to her son.

For thousands of years, sugar has been a luxury item, and it is small and profitable. Jingxi Road is still too far north to grow sugar cane to squeeze sugar. Du Zhongxiao did not want to miss this way of making money, so he turned his mind to malt sugar.

Malt sugar is a type of malt sugar. It has a long history and is sold on the market. It is bought for a small piece of money for a penny to coax children. The sugar price is not cheap, and it is rarely bought and eaten by adults, which is not common. Moreover, the craftsmanship is not exquisite at this time, either too sticky or too hard, and it relies on a little sweetness to attract children. As for the sugar blowers that can be seen almost everywhere in tourist attractions in later generations, Du Zhongxiao has never seen it.

Such malt sugar will naturally not be very good in nature. Du Zhongxiao made improvements based on his memory in his previous life. He chose the sesame seeds here, stir-fry them in the pot, grind them into powder, and stir evenly with the melted syrup. After cooling, cut them into pieces with a knife, and then they become simple crispy sugar. The sugar made in this way is sweet and fragrant, much more delicate than the malt sugar sold on the market. The most important thing is that after processing, it can be divided for a long time, convenient for long-distance transportation, and convenient for large-scale commercial production.

In recent days, Du Zhongxiao asked Shisanlang to lead a few people and continued to try the production, and finally matured slowly. He made two types of black and white sesame seeds, one small piece after another, wrapped in bamboo paper, and the prototype of the candy in later generations has already been formed.

During the trial production days, Du Zhongxiao's son had big pieces of yam, and he couldn't eat enough of this sweet and delicious crispy candy. This candy is not as sticky as malt sugar, and it is very convenient to bite at a bite.

It is not good for the child to eat candy, but there is no such concept at this time. Du Zhongxiao said it a few times, but Han Yueniang didn't believe it, so her son gave it to him as soon as he asked for it. Du Zhongxiao had no choice but to wait until the child had a toothache and then set rules for him.

Seeing that his son was still eating, Du Zhongxiao said to Han Yueniang: "If you eat too much sugar, your teeth will be decayed by insects, and you will suffer sooner or later. Just eat one or two pieces a day to satisfy your cravings, and you can't eat them all. Moreover, the sesame mixed in the sugar is too oily. If you eat too much, you won't even have to eat, and you will have a stomachache."

The son has eaten a lot of candy these days, but it is true that he doesn’t eat much, so Han Yueniang packed up the remaining candy.

At this moment, the chief clerk Cui came in from the front and bowed, "Official, the new chief Su Song has arrived at the yamen and is waiting outside."

Du Zhongxiao looked at the sky and said, "I won't do anything today. I will hold a banquet in the back of the yamen to welcome him."

After saying that, he handed over his son to Han Yueniang, and Li Cui went to the front office together.

After Su Song left office from Yongcheng, he first went to Hangzhou to see his father, then went upstream along the Yangtze River, walked on the Han River, entered the Tangbai River, and took a boat to the place. He walked thousands of miles and was in a hurry.

Du Zhongxiao came out and both sides greeted each other. Du Zhongxiao said, "Thank you for your hard work in Zirong, and I'll go to the back yamen to rest."

When the two arrived at Houya, Han Yueniang had already brought the child back to her residence, leaving only the porcelain basin there.

Du Zhongxiao said: "I have arranged a residence for you there, and I will take you there. By the way, why didn't Zirong's family come?"

Su Song said: "The deadline is urgent. I will go ahead first. They will not arrive in a few more days."

The term of office of an official is calculated on a daily basis. One term of two years or three years refers to the day from the date of office to the date of departure. If you transfer to several places during this period, then add up the number of days. Only when the date is enough will the full term. If you ask for leave in the middle, you will have to deduct it.

Most officials are unwilling to be officials in remote areas. In addition to the difficult conditions, too much time wasted on the road is also one of the reasons. One round and one trip can be repeated for several months or even nearly a year. If you transfer a few more times in the middle, all time will be wasted on the road. Normally, for three years, the Sichuan, Xia, Guangdong and Guangxi are one and two years, so one year will be left for a year. If you are both an official for ten years, you will have bad luck, and you will have to go on the road and be on the road. The term of office is only four or five years, so the gap with your colleagues will be revealed. In this case, the benefits of being an official in the capital will be revealed.

Su Song and Du Zhongxiao were in the same year. Their starting points were similar, but in six or seven years, their official positions were far behind. It was fine if they arrived in Du Zhongxiao. He would be very anxious to travel all the way, and it would be better to arrive one day earlier.

Arranged a residence for Su Song and assigned entourages. The two of them went to the yard again to wait for the dinner.

When they arrived at the place where they had just sat down, Du Zhongxiao looked at the porcelain basin on the ground, and the iron sheets inside had become much smaller.

Su Song saw it and asked, "What is the blue here? Why is it placed here?"

Du Zhongxiao said: "The water has transformed into the alum, so it is blue. I put some iron sheets in it to see if copper can be produced."

Su Song looked down and looked carefully for a while, and said, "The red one on the iron sheet should be copper powder. Ge Hong's "Baopuzi" says that Zeng Qing painted iron, 'iron red like copper', should refer to this matter. But it's just a thin layer, and the iron inside is still iron."

Du Zhongxiao said: "Yes, copper is just a layer on the outside. If scraping it off, the iron inside is still iron. However, if the copper covers the iron sheet, take it out and scrape off the copper powder, then put the iron sheet in, and accumulate a little into more. Can you use iron to smelify copper? I'm going to try it today. If this method is feasible, it will be much easier to smel copper."

"Iron is cheap and copper is expensive. If this method is really feasible, it is a good way to smelify copper."

This is what wet copper smelting must be discussed in chemistry courses, which is a huge progress in China's copper smelting technology. Su Song is familiar with miscellaneous books and is not unfamiliar with this phenomenon and does not think it is very magical. However, in this era, wet copper smelting has not been used, and no one thinks in this direction.

At this time, the largest copper ore in the world was Dexing County, Raozhou. It was rainy and the ore dissolved in water and became a copper sulfate solution, which was actually a solution of bile alum. Du Zhongxiao used bile alum solution instead, which basically simulated the situation there.

When iron is put into copper sulfate solution, a replacement reaction occurs, and the copper metal can be replaced. Although this method is scrapped iron, it can be carried out at room temperature, which not only saves the fuel of copper smelting by ignition, but also greatly improves the production environment and is much lower in cost.
Chapter completed!