Chapter 28 Chapter Seven Strange Earth Buildings

There are a large number of earth buildings in Zhangzhou, Nanjing, Longyan, and Yongding in Fujian, and they are square or round.The exterior is a tall earthen wall with a small number of window holes on the wall, much like a fortress.The appearance of this kind of tulou is not accidental, because there are frequent fights among the clans in this area, and even developed into armed conflicts.In order to protect the safety of one's own clan, the families of a family requested to live together, so this kind of large residence that can accommodate dozens of families appeared.Among these two kinds of earth buildings, the most striking one is the circular earth building, referred to as Yuanlou for short.According to most scholars, this kind of round building should have gradually evolved from the square building.This is because round buildings have more advantages than square buildings in terms of use, structure and construction.For example, a round building can be divided into rooms of the same size without dead ends; the roof construction does not have the criss-cross knots of the square building's ridges; the round building has less resistance to wind; the earthquake resistance is stronger than the square building, etc.The outer diameter of the existing circular buildings is as small as 50 to 60 meters, and as large as 80 or 90 meters. Taking the Yongding Chengqi Building built in the middle of the Qing Dynasty as an example (Figure 25), the outer diameter is about 62 meters. The houses are set together, with a total of more than 300 rooms. The outermost ring is four floors high. The bottom floor is the kitchen and utility room. A place for weddings, funerals and other public events.How did such a large round building achieve the purpose of defense?From the perspective of the structure of the round building, first of all, tall and thick walls are used on the periphery.The walls are less than one meter thick and some are as thick as 2.5 meters. They are all built with lime-mixed loess and compacted layer by layer.This kind of gray earth wall becomes stronger as it ages. Some round buildings have not been damaged even after being bombarded by cannons during the war, which shows how solid it is.The underground foundation of the wall is built with large pebbles, and the pebbles are pressed together very tightly, which can prevent attackers from digging tunnels to enter the building.All the rooms have windows facing the courtyard, so there are mostly no windows outside the walls, and only square gun holes are opened on the upper floor for the defenders to shoot and throw stones.There are very few gates in the whole round building, and Chengqi Building with a diameter of 62 meters has only three gates.Each gate is made of stone as the frame, and the door leaf is made of thick wood, covered with iron sheets on the outside, and two horizontal and vertical bolts are used to support the gate inside.In order to prevent the door from being attacked by fire, a water tank is specially designed above the door, which can put water down and form a water curtain outside the door leaf, effectively preventing fire attack.There are water wells dug in the building, and food is specially stored, all of which are set up to adapt to the situation of long-term war.This kind of folk houses produced under special circumstances has now become a famous residential spectacle both at home and abroad.