The Four Great Inventions(四大发明)

During the Song Dynasty, the Chinese people further developed the marking of the compass, paper, gunpowder, and the art of printing. Together, they are called the four great inventions that China contributed to the world.

As early as the Warring States period the magnetic force of magnetite was discovered, and a sort of instrument was made of magnetite to show directions. This was certainly the earliest compass in the world.

During the Han Dynasty, people made a spoon-like compass. A small spoon, made of magnetite, with a very smooth bottom, was placed on a square copper plate. The center of the plate was ground smooth to make it easy for the spoon to move. When the spoon, after it was turned, came to a stop, its handle would point to the south.

This form of compass was further improved during the Song Dynasty. People made iron needles and rubbed them on a piece of magnetite, so that they would become magnetic. Then one such needle was hung with a thin thread, or put on something light that floated on the water in a bowl. The latter was the compass that was first used in navigation.

It was generally believed that paper was first made by a man called Cai Lun in 105 during the Eastern Han Dynasty. However, in recent decades, earlier paper made during the Western Han Dynasty was unearthed in Xinjiang, Shanxi, and Gansu. So it is reasonable to believe that paper was invented in the Western Han and was improved by Cai Lun in the Eastern Han. In later periods, different materials were used for making paper, and its quality became better and better. The famous Xuan paper, produced in Xuanzhou, Anhui Province, first appeared in the Tang Dynasty. Its quality was so good that all calligraphers and painters liked to use it. Even today it is still considered the best kind of paper for calligraphy and traditional Chinese painting.

During the Song Dynasty, bamboo began to be used for making paper, and the output of bamboo paper increased rapidly.

In 751, during the reign of Tang Xuanzong, the Chinese technique of making paper was introduced to the Arab world, and from there to Europe in 1150. In other words, Europe knew how to make paper about a thousand years late than China.

The Chinese invented gunpowder about 1, 100 years ago. Towards the end of the Tang Dynasty, gunpowder was first used in war. In 904, during a battle between local forces, a weapon then called “flying fire” was used. It was a packet of gunpowder tied to the head of an arrow. After the fuse was lighted, the arrow was shot to the enemy side, and the gunpowder would cause damage or kill men.

During the Song Dynasty, the making and use of gunpowder reached a new level. Various kinds of weapons with gunpowder were invented. The Song, Jin and Yuan armies all used these weapons in war.

Gunpowder was introduced to the Arab world during the 13th century. In the following century some European countries began to make gunpowder weapons with methods they had learned from the Arabs.

Before printing was invented, people had to rely on handwriting to reproduce a book. It was very slow and errors easily occurred.

Wood-block printing first appeared in the early Tang Dynasty. It was developed from the use of seals and stone engraving. Words engraved on stones could last very long, and later, in about the 4th century, the method of rubbing a piece of paper on an engraved stone covered with ink was used to make copies. This gave workers the idea of engraving word on a wood-block and print them with the quick development of the economy and culture in the Tang Dynasty, books and other publications like calendars were needed by the public, and this demand promoted wood-block printing. According to records in certain books, block printing was very common in the late Tang Dynasty.

During the Song Dynasty, the technique of block printing was very advanced. Books were beautifully printed. Even today the books printed at that time are valuable and treasured by libraries and book collectors.

Block printing was not very convenient. Every two pages of a book had to be engraved on a wood block, and a big book would require many blocks. Besides, there had to be large places for storing the blocks. To overcome these shortcomings, Bi Sheng invented the movable type during the years between 1041 and 1048. One word was carved on one piece of clay, which was hardened with fire. Then clay characters were set on an iron plate according to the text of a book. Then ink was applied to them and sheets of paper spread over them, and the printing was done.

Bi Sheng’s invention made printing faster and easier than before. Later, movable type of mental and wood was made and widely used. One county magistrate of the Yuan Dynasty had over 30, 000 wood characters carved, with which he printed a book he had written. It was a book of more than 60, 000 words, and he finished printing 600 copies less than a month.

The technique of printing was gradually known to other Asian countries and Europe. It goes without saying that the printing invented by the Chinese has great influence on the advance of civilization.