What do you mean by caisson?

Smallpox is a component covering the top of a building, and the dome-shaped ceiling in the building is called "algae well". Every square in this ceiling is a well, which is decorated with patterns, carvings and colorful paintings, so it is named algae well.

The word "algae well" was first seen in Han Fu. Many algae wells in Qing dynasty were decorated with dragon patterns, so they were also called "Longjing". In addition, Shen Kuo's Meng Qianbi Tan Yong also recorded some aliases of algae wells: "... the ancients called it Qi Jing, also known as algae wells, also known as Gaihai."

Caisson is usually located in the upper part of the room, umbrella-shaped, supported by exquisite arches, symbolizing the sublimity of the sky. Caisson is generally painted with colorful paintings and reliefs. According to "Custom Pass", "This hall is a patio. Well, so is the image of Tokyo. Ling, something in the water. So Tired Ofthe Fire also. "

Cave Sutra, Jingsu, is one of the twenty-eight lodging places. The ancients thought it was the main water. At the top of the halls and pavilions, wells are built and decorated with algae and aquatic plants such as lotus, water chestnut and lotus, all in order to suppress the fire demon and protect the safety of the building.

Caisson is a kind of superimposed cave roof decoration, which is named because it is similar to the roof structure of ancient buildings in China. Dunhuang caisson simplifies the structure of the traditional ancient laminated wooden caisson in China, with the center protruding upward and inclined on all sides, becoming an inverted bucket with a big bottom and a small top. The theme works are in the central square well, and the surrounding patterns are spread out layer by layer. Because the caisson is located at the top of the center of the grottoes, the top of the grottoes has a lofty and profound feeling.

Like ordinary smallpox, algae wells are also a kind of interior decoration, but algae wells can only be used in the most noble buildings, such as the Buddha statue or the top of the emperor's throne. It was clearly stipulated in the Tang Dynasty that caissons should not be re-arched unless they were the residence of the prince.