火炎焱加冰
Gunpowder 火药Handgun from the Yuan dynasty, circa 1300s.Main article: History of gunpowderThe prevailing academic consensus is that gunpowder was discovered in the 9th century by Chinese alchemists searching for an elixir of immortality. By the time the Song Dynasty treatise, Wujing Zongyao (武经总要), was written by Zeng Gongliang and Yang Weide in AD 1044, the various Chinese formulas for gunpowder held levels of nitrate in the range of 27% to 50%. By the end of the 12th century, Chinese formulas of gunpowder had a level of nitrate capable of bursting through cast iron metal containers, in the form of the earliest hollow, gunpowder-filled grenade bombs.In AD 1280, the bomb store of the large gunpowder arsenal at Weiyang accidentally caught fire, which produced such a massive explosion that a team of Chinese inspectors at the site a week later deduced that some 100 guards had been killed instantly, with wooden beams and pillars blown sky high and landing at a distance of over 10 li (~2 mi. or ~3.2 km) away from the explosion.By the time of Jiao Yu and his Huolongjing in the mid 14th century, the explosive potential of gunpowder was perfected, as the level of nitrate in gunpowder formulas had risen to a range of 12% to 91%, with at least 6 different formulas in use that are considered to have maximum explosive potential for gunpowder. By that time, the Chinese had discovered how to create explosive cannonballs by packing their hollow shells with this nitrate-enhanced gunpowder.
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中国古代的四大发明，英语是： Four Great Inventions of Ancient China.中国是许多伟大发明的发源地，包括中国古代的四大发明：造纸术、指南针、火药、印刷（包括木字和活字印刷）。China has been the source of many significant inventions, including the Four Great Inventions of ancient China: paper, the compass, gunpowder, and printing ( both woodblock and movable type). 重点词汇：invention 英[ɪnˈvenʃn] 美[ɪnˈvɛnʃən] n. 发明; 发明物; 捏造：内心捏造的东西，特指谎言; 发明才能; [例句]It's been a tricky business marketing his new invention宣传他的新发明一直是件棘手的事情。ancient 英[ˈeɪnʃənt] 美[ˈenʃənt] adj. 古代的，已往的; 古老的，过时的; 年老的; 老式的; n. 古代人; 古文明国的国民; 高龄老人; 旗手; [例句]They believed ancient Greece and Rome were vital sources of learning.他们认为古代希腊罗马是知识的重要发源地。
