The distribution of the residents of Chang'an City has two major characteristics, one is that the population in the east is relatively large, and the population in the west is small. This is mainly due to the fact that the eastern part of the country is on higher ground, and people like to live on higher ground when building houses. The second characteristic is that the inhabitants of the northeast are relatively affluent, and the southwest is the slum of Chang'an. Because the northeast was the imperial city and the circle of magnates surrounding it, the southwest was inhabited by low-status commoners.

During the Tang Dynasty, the prosperity of the western market was much higher than that of the eastern market, and one of the main reasons was that the shops in the market were small, and the merchants had to rent the houses of the local residents in order to store their goods and live for themselves. The rent in the eastern part of Chang'an is more expensive, and most of the merchants choose the West Market as a nearby house for the sake of convenient transportation and saving expenses, which causes more merchants in the West Market than in the East Market.

Yongyangfang is a square at the top of the southwest corner of Chang'an City, which is a slum of Chang'an standard, and there are few complete single-family houses, and most of the residents live in large courtyards.

That morning, in a dilapidated house, there was a middle-aged man lying on the bed, who looked pale and listless, and closed his eyes there to recuperate.

At this time, the door was pushed open, and a fifteen or sixteen-year-old lady walked in, this little lady's face was gray, and her appearance was very ordinary, she said, "Daddy, I'm back." Are you feeling better? "The sound is like a hollow valley orchid, which makes people feel comfortable and relaxed.

The middle-aged man opened his eyes and said weakly, "Well, it's much better." ”

Xiao Niang put down the basket in her hand, came to the bedside, helped the middle-aged man sit up and leaned against the head of the bed, and put a pillow on his back to make him more comfortable. She went to fetch a basin of water, served the middle-aged man to wash his hands, set up a small square table on the bed, and then took the food out of the basket and served him to eat.

The middle-aged man said, "Ruoyu, you can eat it too." ”

The little lady's name is Gu Ruoyu, and she said: "Daddy, you eat first, I just came back, rest and eat again, and I'll cook some soup in a while." ”

She stepped aside, fetched a basin of water, lowered her head to wash her face, and when she finished washing her face and wiped off the water marks on her face, her appearance changed miraculously. It turned out that she was wearing makeup when she went out.

Her appearance is difficult to describe in specific words, her eyebrows are like distant mountains, her eyes are like stars, light and distant, timeless and hazy, fresh and brilliant, pure as a child. If Li You sees it, he will definitely say that she is very much like the innocent movie star in later generations. Although she was wearing a gray coarse cloth dress, it was difficult to hide her slender figure and the natural feminine charm on her body.

The little lady's name is Gu Ruoyu, and she said: "Daddy, you eat first, I just came back, rest and eat again, and I'll cook some soup in a while." ”

The middle-aged man continued to eat, Gu Ruoyu lit the honeycomb coal stove, boiled the water, and returned to the bed to sit down. She stared at her father, and stopped talking.

The middle-aged man saw his appearance. said: "Ruoyu, is there anything interesting outside today?" He was bored in the house every day, and Ruoyu usually came back to tell him about the things he encountered when he went out.

Gu Ruoyu said cautiously: "Daddy, the imperial court has posted a notice to hold an engraving skills competition, and the main items are woodcarving, tooth carving and copper carving. ”

"What, bronze?" The middle-aged man said in surprise.

"Yes, Daddy." Gu Ruoyu said.

Three years ago, they came to Chang'an from Jinyang to make a living engraving for a bookstore, but because of his disability, the speed of engraving was slow, and he could only carve the cover and title page of the book, barely making ends meet.

Gu Kun's eyes brightened for a moment, and then he regained a gloomy expression, and he asked, "What does the notice say?" ”

Gu Ruoyu said: "This engraving skills competition is presided over by His Royal Highness the King of Qi and Lord Wei Zheng, and the winners of the competition can get rich rewards, and they can also enter the palace of the King of Qi to do things and enjoy the royal court." Daddy, my daughter thinks you can try. ”

Gu Kun quickly shook his head and said, "Forget it, I still won't go." ”

Gu Ruoyu said: "Daddy, your bronze engraving skills should also be revealed, why do you refuse to use it?" ”

Traditional cultural and artistic carving, the general people are familiar with seal carving, bamboo wood carving, pottery carving, tooth carving, brick carving and so on. Only the copper engraving is not well known. As the name suggests, the art of copper engraving is taught in copper, which is an art that integrates calligraphy, painting, seal carving and many other arts. The copper engraving is declining, and the knife is limited to the square inch, and there are many difficulties in delicate operation. It is mainly used for copper handicrafts such as the four treasures of the study, jewelry rings, etc.

Gu Kun often closes the door at home, secretly engraving copper, and the products he carves can be described as unique and beautiful, but he never refuses to take out the carved products for sale. Often, after carving, they were destroyed with their own hands, and then wept silently there.

Gu Ruoyu asked him more than once why, but Gu Yan refused to say it, and asked her to keep it strictly secret.

Seeing her father shaking her head again, Gu Ruoyu stopped asking, filled a bowl of soup, handed it to Gu Kun, and began to eat herself.

Qi Wangfu.

Li You said: "Lord Wei, the anti-counterfeiting technology of banknotes can be engraved and intaglio printing. ”

The printing of soft sister coins is mainly intaglio printing (some are printed with letterpress and offset printing), which is mainly to ensure its seriousness and anti-counterfeiting. Gravure plate is engraved, its pattern line is grooved, lower than the layout of the printing plate, after the ink is printed out of the pattern, the ink is attached to the banknote paper, protruding from the surface of the paper, the graphic lines are fine, the layers are rich, the three-dimensional sense is very strong, and there is an obvious sense of concave and convex when touched by hand. The engraving and gravure printing technology is widely used in the fifth set of renminbi portraits of great people, bank names, denomination numbers, Braille marks, etc. In particular, the head of the great man is hand-engraved intaglio, with its complex process, unique pattern and high investment cost, etc., with strong imitability and anti-counterfeiting performance.

Although Li You had the advanced technology brought by the science and technology library, he lacked the corresponding materials, cutting tools, etc. in the Tang Dynasty, and he originally thought about building cars and airplanes in the future, but he found that in this era, even a screw could not be made.

He originally wanted to make an engraving intaglio printing press, but found that it could not be done with the level of Tang Dynasty craftsmen, so he adopted engraving printing, cross-printing with the stereotypes of multiple craftsmen. Even so, it can still be imitated by Gao Henian and others.

Eventually, he came up with the idea of using copper engraving and gravure printing technology, and the manufacturing department had an all-in-one machine to make different engravings, print different parts, and then combine them with other engravings to print dark and other marks on a seasonal basis. With these means, with the addition of exclusive secrets such as printing paper and special inks, the anti-counterfeiting of banknotes can basically be foolproof.

In order to keep improving, Li You decided to hold an engraving art competition, select engraving masters, and then verify their identities to complete the printing and engraving of banknotes.

On this day, the engraving art competition was officially held in the palace of the king of Qi, and 81 engraving masters from Chang'an and surrounding state capitals participated in the competition.

Soon after the start of the competition, a young lady came to the door of the Qi Palace.