It is a popular saying that China is an inland agricultural country with backward ocean shipping and shipbuilding technology since ancient times. This is the fallacy of not understanding history. A large number of archaeological objects prove that ancient Chinese shipbuilding and navigation technology used to lead the world for a long time. The three most famous inventions are the compass, the rudder and the watertight cabin.

The invention and use of the rudder

Ruo is also written in ancient books, such as Tuo, Shi, Pao, etc., whose names began in the Eastern Han Dynasty. Liu Xi's "Shi Ming·Shi Chuan" said: "The tail of the ship is called 柁. 柁, tow, and tow in the back. Moreover, the boat is straight, so that the flow does not make him guilty." This explains the stern of the ship at that time. There is a rudder, which enables the ship to correct its course and not deviate from the course.

Through the archaeologically discovered Han Dynasty wooden ship models and the Han Dynasty ship patterns on the bronzes, we can clearly see that the rudder evolved from an oar. For example, a model of the Western Han wooden boat buried in Jiangling, Hubei Province, was unearthed in 1974. There are five figurines and five oars on the boat. One figurine is on the stern side of the boat, and the other four are rowers. Although they are all paddles, they have different functions. The propeller evolved into a rudder, with three key changes. The first is the shape of the paddle: for ease of handling, the handle of the paddle is lengthened, and the area of the paddle is enlarged in order to increase the force of the water flow. The second is the operating position: moving from the side of the ship to the stern of the ship, and finally placed in the middle of the stern. The third is the operation mode: it is changed from hand-held operation to fixed on the supporting point, which can either rise or fall according to the depth of the water, or it can be flexibly rotated according to the heading.

In 1955, a pottery boat was unearthed from an Eastern Han tomb in Guangzhou, which is naturally also a artifact. There are 6 people on board. Scientists calculated according to the height ratio of the people on board. The ship modeled after this pottery ship is about 20 meters long and 5 meters high. It is a transport ship sailing in the rivers of Guangzhou. There is a real rudder in the middle of the stern of the ship. The rudder surface is an irregular square, with a relatively large area; there is a hole at the top of the rudder stock, which may be used to install the rudder handle; the rudder stock is fixed with a cross-shaped structure and extends into the water obliquely from the stern, the researchers determined This is a device that pivots the rudder. One person standing beside the rudder shall be the steerer.

In 1957, a large rudder stock with a length of 11.07 meters was unearthed in Zhongbao Village, outside Hanzhongmen, Nanjing, with a slightly square cross-section. There are two rectangular perforations at the upper end of the rudder stock, which are used to install the wooden handle for steering the rudder; the lower half has a tongue and groove for the installation of rudder blades. According to the position and size of the tongue and groove, it is inferred that the height of the rudder blade is about 6 meters. The rudder stock is made of iron wood, which is a very hard high-quality wood.

When the rudder rod was transported to the Chinese History Museum for exhibition in 1959, due to site problems, it had to be cut into two pieces. People can really see that although the rudder rod has been buried in the ground for more than five hundred years, it is not decayed. sign. The place where the rudder stock was unearthed was the Bao Shipyard in the early Ming Dynasty, where the large ships Zheng He sailed to the west were built.

In the years before and after the large rudder stock was unearthed, some ancient ship components were also unearthed, the texture of which was also iron wood. Everyone knows that there is a certain proportional relationship between the size of each component of a ship. After calculations, experts believe that this large rudder stock should be installed on a large ship about 150 meters in length.

According to "Xingcha Shenglan", the largest ship in Zheng He's fleet was "forty-four feet and four feet long and 18 feet wide." At that time, 1 foot was 31.1 centimeters today. Based on this calculation, the largest ship of Zheng He's fleet was 138 meters long and 56 meters wide. This size is more compatible with the large rudder stock. Therefore, people think that this rudder stock should have been used and retained by Zheng He's fleet.

The invention and use of the rudder is a major contribution of the Chinese nation to the world's shipbuilding and water transportation. It was introduced to the West along with the compass that began to be widely used in the Song Dynasty and made the 15th century great nautical era.

Watertight cabin

Another major invention of the Chinese nation in shipbuilding is the watertight compartment. This invention has saved the lives of many ships and people.

What is a watertight compartment? Simply put, it is to divide the cabin into multiple compartments that are not connected to each other with wood planks, fillers, etc. When sailing, if one compartment is seriously flooded, it will not be poured into other compartments, which can avoid sinking. Disaster. Regarding the construction of watertight compartments, it has long been considered that "begins in the Song Dynasty". However, the wooden boats of the Tang Dynasty unearthed in Yangzhou and Rugao, Jiangsu Province, have a watertight compartment structure, which has changed the previous understanding.

The Tang ship in Yangzhou was unearthed in 1960, with a remnant length of 18.4 meters, a widest point of 4.3 meters, and a depth of 1.3 meters. It was divided into 5 large cabins, belonging to the late Tang Dynasty. The Rugao Tang Ship was unearthed in 1973, with a remnant length of 17.32 meters, a widest point of 2.58 meters, and a depth of 1.6 meters. It was divided into 9 cabins, belonging to the early Tang Dynasty.

It can be seen that the wooden boats of the Tang Dynasty from the early to the late period adopted a watertight compartment structure. The Song and Yuan Dynasties were the most developed period in ancient my country for overseas transportation and trade, which inevitably led to the development of the shipbuilding industry, especially the marine shipbuilding industry.

Quanzhou was one of the three major centers of foreign trade at that time, and it also had a developed shipbuilding industry. In recent years, shipbuilding sites and sea-going ship debris have been discovered here. Among them, the sea-going ship unearthed in 1974 is written into the history of various places. Textbook, here is a more detailed introduction. The upper part of the hull of the ship has been damaged, and only the part that belongs to the water is well preserved. This is the key part of the ship, which allows people to understand the shape and structural characteristics of the ship. The residual length of this ship is 24.2 meters, the residual width is 9.15 meters, and the residual depth is 1.98 meters. Based on this, it is estimated that its upper part should be about 35 meters long, with a displacement of 400 tons up and down, and a load of about 200 tons. A small sea-going ship in the Song Dynasty. The ship is divided into 13 compartments, and the thickness of the wooden boards of the compartments is 10-12 centimeters. The wooden boards are joined by tenon and tenon joints, and the bulkhead and the hull are first connected by flat iron and hook nails, and then filled with hemp, tung oil, and lime to seal all the gaps. Such materials, connection and sealing technology ensure the firmness and durability of the compartment. Due to the structure of the watertight compartment, the ships of the Song and Yuan dynasties frequently sail to the sea and go back and forth safely. They are admired by all countries and gradually adopted by countries from the 18th century until modern times.

Watertight cabin technology

The watertight cabin technology used in shipbuilding actually appeared as early as the Jin Dynasty. Ships made with this technology had a unique name "Eight Slot Ships" in the Eastern Jin Dynasty.

What is the "Eight Slot Ship"? It is to divide the lower draft of the hull into eight cabins during shipbuilding, so that even if one of the cabins leaks during the voyage, it will not cause the ship to sink.

The earliest application of this technique was the famous pirates Sun En and Lu Xun during the Eastern Jin Dynasty. According to "Annotation to Yixi Life", "Lu Xun's new eight-slot ship nine pieces, with four floors and more than ten feet high." "Song Shu. Wu Di Ji" also recorded "the same day, it will be issued in Baling, and the Dao will be connected with the flag. Next, there are nine ships with eight slots, four stories high and twelve feet high."

In fact, the word "zhou" in the Shang oracle bone inscriptions is a pictogram, but there are three horizontal lines in the word "zhou". Some people think that this symbolizes that shipbuilding already had the technology of compartment separation at that time.

Some Western scholars (Needham) believe that the watertight bulkhead technology originated from the Chinese observation of bamboo, because there is a partition in the middle of each section of bamboo.

American science and technology historian W. Smith said: "The idea of building a ship's bottom tank sealing wall is very natural. The Chinese got this inspiration from observing the structure of bamboo poles. The diaphragm of bamboo pole sections divides the bamboo into many diabolo tubes. Because of Europe There is no bamboo, so Europeans have no inspiration for this."

"This technology has many advantages. One is that after one cabin leaks, it will not affect the use of other cabins. The second is that there are many more support points inside the ship, which increase the strength of the hull. The point is to provide a strong horizontal structure for the hull, so that the mast can be tightly connected with the bulkhead of the hull. This technology later made it possible for shipbuilding to adopt multi-mast and multi-sail."

In other words, it is difficult to build a large ship with multiple masts without multiple dense cabins. This ancient Chinese shipbuilding technology was introduced to Europe and adopted in the 18th century. According to the history of Western ships, the first European application of watertight bulkhead technology was the British naval engineer Samuel Bentham. In 1782, he followed the instructions of the British Secretary of the Navy to design and build the first ship with keel and more. A warship with a bulkhead. This was a very advanced ship in Europe at the time.

At the UNESCO meeting in 2010, China's wooden boat watertight cabin manufacturing technology was included in the list of intangible cultural heritage in urgent need of protection. Author/He Xin, Editor/He Yuting