IX. SCIENCE & TECHNOLOGY. 1. Name four great inventions of China? . Compass, gunpowder, papermaking and printing. 2. Paper is one of greatest inventions in China. When and by whom it was invented? .
2. Paper is one of greatest inventions in China. When and by whom it was invented?
In 105 BCE, CaiLun (蔡倫) invented the composition for paper along with the papermaking process.
3. Why did Bi Sheng’s (畢昇) invention of printing by movable type in 1045 have far less impact on China than Gutenberg’s similar invention four centuries later in Europe?
Because the quantity of Chinese characters, printing in Chinese was much more laborious.
4. Zhang Heng (張衡) was the greatest inventor, mathematician, astronomer and geographer in Chinese history. What field of his work has often been compared to that of Ptolemy (AD 90–168)?
5. Gunpowder was one of the greatest inventions in China. When did the Chinese start using it?
The Chinese discovered gunpowder before 255 BCE, but used it only for fireworks until much later. Isolated instances are given of its use for military purposes, in 767 CE and 1232 CE, but cannon were not used for the defense of the Great Wall until the Ming Dynasty in 1368 CE, about the time they were first used in Europe.
6. Why was the knowledge of medical science in China behind that of the western world?
The Chinese had very little knowledge of medical science and even less of anatomy because of religious convictions against mutilation of a dead body and the drawing of blood. Hence they practiced almost no surgery. They placed great reliance on diagnosis by the pulse. They claimed that by taking the pulse at different places, they could tell the state of health of the different organs, and even determine the sex of an unborn infant.
The Great Wall did not prevent large invasions (the Tartars breached it many times). But such intrusions were made possible by the weakness and/or disloyalty of the defenders rather than by any weakness of the Wall itself. For example, when Genghis Khan (1162 – 1227) invaded China, he bribed his way through a gate in the wall.
The Three Gorges Dam (長江三峽大壩). It is the world's largest power station in terms of installed capacity (20,300 MW) but is second to Itaipu Dam with regard to the generation of electricity annually.
As well as producing electricity, the dam increases the Yangtze River's shipping capacity, and reduces the potential for floods downstream by providing flood storage space. The Chinese government regards the project as a historic engineering, social, and economic success, with the design of state-of-the-art large turbines, and a move toward limiting greenhouse gas emissions. However, the dam flooded archaeological and cultural sites and displaced some 1.3 million people, and is causing significant ecological changes, including an increased risk of landslides. The dam has been a controversial topic both in China and abroad.