On this topic, some people jokingly called the Forbidden City a place where birds don't. In fact, the Forbidden City is not only birds do not, the roof does not grow grass. The Forbidden City is so large, the number of houses is so large, why is the most difficult problem for ordinary people to solve the problem of roof being pulled by birds and long grass, the Forbidden City is not worried at all?
In fact, there are two main reasons for the question of why there is no bird feces on the roof of the Forbidden City:
During the feudal period, the imperial palace would have a special cleaning eunuch, regularly repairing the house and cleaning up the garbage. For example, during the Ming Dynasty, the emperor would set up a camp under the Ministry of Works to build and repair the palace, and this department concentrated countless skilled craftsmen across the country.
In the Qing Dynasty, the responsibilities of the Ministry of Works and the Ministry of Internal Affairs intersected, at this time the Ministry of Works was responsible for the temples, official offices and other buildings in the capital, while the Construction and Repair Work of the Forbidden City and the Imperial Garden was managed by the Department of Construction of the Ministry of Internal Affairs.
As for the time of repairing the imperial palace, it is about an opportunity for overall repair in about 3 years, and the eaves and rafters are replaced once every 5 years, and large buildings such as the Taihe Hall are generally renovated once in about 10 years. In addition, the Construction Department also has to conduct regular "physical examinations" of the buildings of the Forbidden City, which is more frequent and will be carried out almost every year.
Taking the Cining Palace as an example, on July 25, 1958, qianlong, the General Administration of Internal Affairs presented a list of new leakages in the Cining Palace and other places and the bursting of oil decoration in the door sill frame roughly recorded the "physical examination report" of the Cining Palace: after verification, it was found that there were many new leakages in the Cining Palace, and there were oil decoration bursts in the door leaf frame.
And the so-called "physical examination", in addition to finding and solving these practical problems, the rest is to clean up these palaces, such as often to the roof to see if there is bird droppings and newly grown weeds, although the roof of the Forbidden City is anti-bird feces and weeds, but also can not stand the accident Ah, in case a bird in the process of flight pulled a bubble fell on the roof, it is no way.
Second, "the warbler does not fall on the top of the wall" and "the golden tiles of the Zhu Wall, the golden nails of the Zhumen Gate" can be said to be the biggest feature of the construction of the Forbidden City. Folk legend has it that the roof of the Forbidden City is made of gold, because every noon, the tiles of the Forbidden City will sparkle like gold. In fact, the roof of the Forbidden City is not made of gold, but made of a special kind of tile "glazed tile".
This kind of tile is different from ordinary tile, after all, the royal thing needs a little attention. Glazed tile firing process is very complex, material selection, design, molding, vegetarian firing, etc. require 36 processes, this tile has a characteristic, it is burned out after the surface is very smooth, just like glass, and in the light when the light is strong will reflect.
In addition to the fact that the surface is very smooth and has a certain inclination, the glazed tile also adopts a design method called "warbler does not fall to the top of the wall". Literally, even the "warbler" doesn't want to fall on it. We see that the style of the tiles of the Forbidden City is very different from the ordinary tiles, the Forbidden City uses "barrel tiles", and from a distance, it is like a "roll" juxtaposed on it.
And the width of this "roll" is basically greater than the toe spacing of all birds, these birds can not stand on the top, the front is also mentioned, the glazed tiles are very smooth, coupled with no foothold, many birds will slide down as soon as they stand up, over time, these birds will not touch the roof of the Forbidden City, since there is no bird naturally there is no bird droppings.
It is precisely because the Forbidden City uses such "technology" as glazed tiles that it scientifically reduces the possibility of birds pooping on the roof, after all, the emperor has to live in the palace, and these craftsmen must prevent birds from pooping on the emperor's head when designing! Even if some birds are accidentally pulled, the craftsmen must also deal with it quickly, if this matter is known to the emperor, those birds have run away, but the unfortunate ones are the craftsmen who repair the palace!
In the same way, the roof of the Forbidden City does not grow grass is the same principle, after all, even the birds can not stand, let alone the seeds, it is estimated that a rain rush down, do not need craftsmen to go up to clean, everything is washed down. As for the founding of the People's Republic of China, there are special staff to do the repair work of the Forbidden City.