Four Great Inventions

China is one of the countries with ancient civilizatioins in the world.The ancient China was rather advanced in the fields of science and technology.The book Science and civilization in China written by internationally noted scholar Professor Joseph Needham,Presents and elegant picture of the splendid culture of science and technology in ancient China.The Chinese people,who are industrious and wise,have contributed to the whole wolrd a great number of inventions and creations,of which the most well-known are undoubtedly the four great inventions,i.e.the compass,papermaking,the technique of printing and gunpowder.

COMPASS

Before the compass was invented,most people identified the direction at sea,only depending upon the position of the sun and stars.If it was cloudy or rainy,people would lost direction in this way.It was the compass,invented by the Chinese people,that solved this problem

The compass is the instrument used for indicating direction.As early as the Warring States Period(475 BC-221 BC),the Chinese discovered that a magnet could be applied to indicate the south or the north,and a direction-indicating instrument sinan was made on the basis of this feature.The instrument comprised a smooth magnetic spoon and a copper plate carved with directions;the handle of the spoon pointed south,and the head north. In the Song Dynasty,people combined an artificially magnetized compass with an azimuth plate to creat a proper compass called luopan,which in any cases,could tell silors the accurate direction.

In the northern Song Dynasty(960-1127),the compass was being applied to navigation.In the Souther Song Dynasty,the instrument was introduced to Europe via Arabia,and Arabs at that time called it affectionately “ The Eyes of Sailor”

The invention of the compass had an epoch-making influence on navigation,thereby opening up a new era in the history of international navigation. Zheng He’s fleets made seven voyages across seas to Southeast Asia and around Indian Ocean in the early Ming dynasty,Christopher Columbus discovered the New world and Ferdinand Magellan sailed round the wolrd in the 15^th century,which was the consequence of the application of the compass to the navigation.

Papermaking

Before papermaking technology wa invented,the Chinese caved or wrote characters on tortoise shells,animal bones,bamboo slices,wooden plates,and thin tough silk. Tortoise shells,animal bones and wooden plates were too heavy to use while silk was too expensive. In the early years of the Western Han Dynasty(206BC-25AD),someone used hemp and ramie to produce the paper,which wa very rough and not suitable for writing.

Till the Eastern Han Dynasy(25-220 AD),an offical named Cai Lun improved the papermaking technique after long-term experimentation. He used various kiinds of plant fibers,bark,rags,and torn fishing nets as raw materials. He steamed and cooked all those materials with water,and pounded them into pulp,then rolled the pulp out evenly on a fine screen and dried it into a kind of thin paper. The paper was suitable for writing and was also very cheap so it became very popular. Therefor,Cai Lun’s contribution to the papermaking was great.

After the Eastern Han Dynasty,the papermaking technology had been gradually improved. Gradually,bamboo,straw and sugarcane residue could also be used as the raw materials for making paper. Due to different materials,various types of paper were produced for different uses. For expample,the Xuan paper made in Xuanzhou of Anhui province belongs to the high quality paper exclusively adapted for use in Chinese calligraphy and painting.

The technology was introduced to Korea and Japan in the late Sui(581- 618) and early Tang(618-907) dynasties,and later to Arabia and other countries.
The invention of paper provides a more convenient way for the storage and communication of information,and also has an epoch-making significance on the promtion the development of global civilization.

Printing

Before printing was invented,a scholar had to do the transcription word for word if he wanted to own a new book. In the Sui and Tang dynasties,the technology of block printing ws invented,and therefore the speed of printing was increased. But when a book was to be printed,many wooden blocks had to be engraved so it was rather troublesome. Till the Northern Song Dynasty more than 900 years ago, Bi Sheng invented movable type printing after the repeating experimentations. He engraved the characters on small pieces of clay,and heatd them untill they became hard movable characters. In the course of presswork,the moveable characters were placed into a whole block in accordance with manuscripts to be delivered to the printing.All those moveable characters could be removed from the block after the presswork for the later reuse of them. This technique invented by Bi sheng was both economical and timesaving, thus brought the technique of printing into a new era

China’ movalbe type printing as first introduced eastward to Korea and Japan,and then westward to Persia and Egypt. The invention of the technique of printing greatly sped up the international development of culture and exchanges. It is no doube that the moveable type printing is one of the greatest contributions to the world

Gunpowder

The formula of the gunpowder was initially discovered by Taoistalchemists of ancient China when they attempted to make pills of immortality. Afterward,according to the formula,some people produced black gunpowder using a mixture of niter,sulfur and charcoal in a certain proportion.In the middle years of the Tang Dynasty,some books recorded the method of producing this kind of gunpowder. After its invention, the gunpowder was first used to produce firecrackers and fireworks,and began to be applied to the military affairs till late years of the Tang Dynasty.

In the Northern Song Dynasty,gunpowder had been in the extensive application to the military affairs,and then weapons such as firelock, rocket and cannon already emerged.

In the time between 1225AD- 1248AD,the gunpowder and weapons using gunpowder were introduced to Europe via Arbia. Since niter,the major raw material of the gunpowder, is as white as snow. Arabians called the gunpowder “ Chinese Snow” and Chinese Salt. After the introduction of gunpowder to Europe,the gunpowder was not only extensively applied to weapons industry,but also various projects such as exploding mountains,road constructin,and river excavation. The invention of gunpowder accelerated the advent of the Industrial Revolution.