What is the building of Phoenix quadrangular octagonal algae well?

Caisson is a unique decorative part of indoor ceiling, which is very common in palaces and temples in Han Dynasty. Generally, it is made into a well shape protruding upwards, with a square, polygonal or circular concave surface, and decorated with various flowers, algae, wells, carvings and paintings. Mostly used in palaces, temples, thrones and the most important parts above the Buddhist altar.

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 layered wooden caisson of Han nationality, with its 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.