My system is not decent

Chapter 1815 Blessed by the sunshine, the fiber is not damaged

In archaeological excavations, the "co-casting type" is often seen.

That is to say, there are two pottery molds for each mirror. Patterns are engraved on the back of the mirror, and the concave part of the mirror button is engraved in the center, and a short and thin rod-shaped "sand core" is made of clay of the same quality as the mold, and it is embedded in the middle of the mirror mold. .

The mirror surface is engraved into a concave plane, and then the two patterns are combined into one.

When casting the mirror, put the sprue upright and slowly inject the copper solution.

After the solution is cooled, take out the cast mirror and grind it to identify the volume.

During the Spring and Autumn Period and the Warring States Period, delicate and exquisite bronze mirrors with hollow patterns appeared.

This kind of bronze mirror adopts the method of separate casting, casting the mirror surface and mirror back decoration separately, and then clamping them together.

This kind of composite bronze mirror basically disappeared after the Warring States Period.

In the production practice, ancient craftsmen in our country constantly summarized the skills of smelting and casting bronze mirrors.

As early as in "Zhou Li · Kao Gong Ji", the alloy ratio for making bronze mirrors was recorded.

"Half of gold and tin is called the quality of the tunnel." That is, 50% copper and 50% tin are the mixture of casting mirrors.

This valuable document is considered by most scholars to be a work of the Warring States Period.

But it should be said that it also includes a summary of bronze casting experience since the Shang and Zhou dynasties.

After the Warring States period, craftsmen continued to explore and experiment.

According to the chemical analysis of modern scholars, the alloy composition of various bronze mirrors has great differences in the proportion of copper and tin due to the different regions and times of production.

Since the Warring States period, copper mirror alloys generally contain lead.

After lead is added to the alloy, the quality of copper mirror casting has been improved.

Lead makes the alloy solution circulate particularly well in the casting mold;
Lead can make the surface of cast products extremely even;
The characteristic that lead will not shrink when condensed can be used to make the pattern on the back of the cast mirror particularly neat and clear;

Lead can reduce the bubbles that are prone to occur when copper and tin alloys are dissolved, and avoid the occurrence of trachoma and other problems.

In the Han Dynasty, the technology of making bronze mirrors improved again.

In particular, the invention of the light-transmitting bronze mirror in the Han Dynasty is another milestone in the mirror casting process.

The light-transmitting mirror was invented in the Western Han Dynasty, and its shape is the same as that of ordinary mirrors.

But when the light shines on the mirror surface, the wall opposite to the mirror surface will reflect the images of patterns and inscriptions on the back of the mirror, which the ancients called "phantom mirror".

Ancient Chinese scholars have long discovered the light-transmitting effect of light-transmitting mirrors.

"Taiping Guangji" records: The ancient mirror obtained by Wangdu of the Sui Dynasty "under the sunshine, the ink and writing on the back will enter the shadow without damage."

Song Dynasty Zhou Mi's "Clouds and Smoke Passing Eye Records", Shen Kuo's "Mengxi Bi Tan", Jin Dynasty Ma Jiuchou's "Fu Boyu Light-Transmitting Mirror" poem, Ming Dynasty Lang Ying's "Seven Revised Class Drafts", Qing Dynasty Zheng Fuguang's "Mirror Mirror (Bell) Crazy" "Etc., there are records and studies on light-transmitting mirrors.

After liberation, two light-transmitting mirrors were first discovered in the sea, and they were successfully copied after research by Shanghai Jiaotong University, finally uncovering the mystery of the "illusion mirror".

Studies have shown that the light transmission of the copper mirror is caused by the internal stress of the copper mirror during the process of cooling and processing the mirror surface.

When casting a mirror, the thinner part of the mirror is cooled first, and the thicker part is cooled later, and the shrinkage of copper is large, so that various parts of the mirror surface have unevenness and curvature differences corresponding to the images on the back of the mirror.

As a result, although the pictures and texts are on the back, there are some hidden signs on the mirror.

Therefore, once the sun shines, the decoration on the back will be reflected.

This kind of technological improvement reached its peak in the Tang Dynasty.

The bronze mirrors of the Tang Dynasty are even more unique. The Tang mirrors have various shapes and are cleverly used. Most of the bronze mirrors are round, followed by square.

During the Tang and Song dynasties, with the development of casting technology, bronze mirrors broke the traditional round and square system in the past.

In this period, according to the requirements of use and decoration, mirrors with handles and bronze mirrors such as octagonal, diamond-shaped, octagonal, square-shaped, rounded square, sub-shaped, cloud-shaped, and chicken heart-shaped were cast.

As for the Song Dynasty, influenced by the ancient customs, the antique tripod-shaped and antique bell-shaped bronze mirrors were cast, which are more contemporary.

The size of ancient bronze mirrors in my country varies widely, but they can be roughly divided into three categories: large, medium and small.

Small copper mirrors generally range in size from 3 cm to 8 cm. They are small and light, and are tied around the waist with a rope for carrying around.

Medium-sized bronze mirrors range in size from 10 cm to 39.4 cm. They are thick and exquisite. When in use, they are either hung on the wall or placed on the mirror stand.

Gu Kaizhi, a painter of the Jin Dynasty, has a detailed description of the use of bronze mirrors in the famous "Nv Shi Zhen Tu".

A man sits on the left side of the painting, facing a mirror stand, and a woman behind him combs his hair with a comb.

There is another man on the right, with his head slightly raised, facing another mirror, and his face is reflected in the mirror.

The mirror stand in the picture is floor-standing, the pole is inserted into the mirror button, and there is a tray in the middle of the mirror stand.

Beside the characters, there are mirrors and other objects.

In 1986, Jiangsu Province exhibited a Han Dynasty bronze mirror in the exhibition of cultural relics census results.

A copper bracket is inserted in the button, which is the same as the mirror stand in Gu Kaizhi's "Nv Shi Zhen Tu".

Due to the small size of these mirror tables, they are often made of expensive materials.

In the literature from the Three Kingdoms to the Southern and Northern Dynasties, there are records of "sterling silver mirror stands", "tortoise shell fine carved mirror stands", "jade mirror stands" and so on.

There is also a kind of mirror stand for placing on the table case, which is particularly exquisite in craftsmanship, but it is relatively late.

Because after the Song Dynasty, the seats were higher than before, and the furnishings of one table and two chairs were gradually finalized, and furniture such as high mirror tables appeared, similar to modern dressing tables, and the mirrors were fixed on top with frames.

Large bronze mirrors, what we call full-length mirrors, are mostly displayed in palaces and homes of princes and dignitaries.

There are many records about this kind of bronze mirror in ancient history, and the one that reminds us most is the story of Zou Ji satirizing King Wei of Qi and accepting advice in "Warring States Policy Qi Ce".

At the beginning of the article, it said: "Zou Ji has more than eight feet (today's 185cm), and his body is beautiful (sound yi). Looking into the mirror in court clothes..."

Zou Ji put on his clothes and hat, and looked at his appearance in the mirror.

According to records, there used to be a large square mirror in Xianyang Palace in Qin Dynasty, which was 4 feet wide and 5 feet 9 inches high.

From Wei Jin to Sui and Tang Dynasties, extra large bronze mirrors were also cast.

After Jin destroyed Wu, a great writer, Lu Ji, entered Luo from Wu.

In front of the Hall of Renshou, we also saw a large bronze mirror, more than 5 feet high and 3 feet 3 inches wide.

Standing in the courtyard, the whole body can be illuminated very clearly.

Later, there was another Huren Shile who dominated the north. In his palace, there was a large mirror with a diameter of two or three feet, and a pure gold seat decorated with coiled dragons.

When Emperor Yang of the Sui Dynasty was living a dissolute and shameless life in Milou in Yangzhou, a courtier named Wang Shichong was promoted to an important position in Jiangdu Tongshou because he donated a bronze mirror screen to please Emperor Yang.

When Tang Zhongzong Li Xian was the emperor, he also ordered the mirror casting factory in Yangzhou to cast the abbot mirror.

Make another copper pillar, inlay many gold flowers and silver leaves, and place the abbot's mirror upstairs in the palace garden.

Zhongzong rode a steed, facing the mirror, looking at his majestic posture on the horse, very proud.

(End of this chapter)