Four Great Inventions of Ancient China is the world's four great inventions impact. Namely, papermaking, the compass, gunpowder, movable type.
星系名称       四大发明是指中国古代对世界具有很大影响的四种发明。即造纸术、指南针、火药、活字印刷术。
(一)Compass八年级下册数学期中试卷
       Compass is used to determine position of a simple instrument. Formerly known as Sinan. The main components are mounted on a shaft can freely rotate the needle (commonly known as magnet). Needle on the ground magnetic field can be maintained at the tangent magnetic radial direction. Needle points to the geographical North Pole South Pole, take advantage of this performance can be a sense of direction. Commonly used in navigation, geodesy, travel and military and so on.
(一)指南针
    指南针是用以判别方位的一种简单仪器。前身是司南。主要组成部分是一根装在轴上可
以自由转动的磁针(俗称吸铁石)。磁针在地磁场作用下能保持在磁子午线的切线方向上。磁针的北极指向地理的南极，利用这一性能可以辨别方向。常用于航海、大地测量、旅行及军事等方面。
    Compass invented the ancient Chinese practice of long-term understanding of the results of magnetic objects. Ancient Chinese people into contact with magnetite, as he began to understand the nature of magnetism. It cited the first to discover the magnetic properties of iron. Then they discovered that the directivity of the magnet. After many experiments and studies, and finally invented the compass can be useful.
       指南针的发明是中国古人在长期的实践中对物体磁性认识的结果。古代中国人接触了磁铁矿，开始了对磁性质的了解。人们首先发现了磁石引铁的性质。后来又发现了磁石的指向性。经过多方的实验和研究，终于发明了可以实用的指南针。
       
 (二)Gunpowder
       With saltpeter, sulfur and charcoal made from these three kinds of material mixed, but when people have these three kinds of things as the treatment of drug, so the name "gunpowder", meaning "fire medicine."
（一）火药
  用硝石、硫黄和木碳这三种物质混和制成的，而当时人们都把这三种东西作为治病的药物，所以取名“火药”，意思是“着火的药”。
电脑宝贝怎么养
    Since the Qin and Han dynasties, alchemy home sulfur, saltpeter and other items make pills of immortality, from the accidental explosion of the phenomenon of inspiration, and then after repeated practice, and found the powder formula. Wei during the Three Kingdoms state-owned smart technician Ma Jun, the method of gunpowder wrapped in paper made the entertainment of "explosive battle", created a powder application of precedent.
        自秦汉以后，炼丹家用硫黄、硝石等物炼丹，从偶然发生爆炸的现象中得到启示，再
经过多次实践，到了火药的配方。三国时魏国有个聪明的技师马钧，用纸包火药的方法做出了娱乐用的“爆仗”，开创了火药应用的先河。
         In the end of theTang Dynasty, gunpowder began to be applied to the military. People use riprap stone projectile machines, fire kits lit after the projectile out, burn the enemy, this is the most primitive artillery. Later, people will head spherical powder dressing in the shaft near the point of the lead after the shot with bows and arrows to gunpowder to burn the enemy. There is also the gunpowder, poison, coupled with some bitumen, tung oil and so on, stir together with poisoning caused the ball, lit after injection with bows and arrows, anti-enemy was a "million people in the enemy." By the Song dynasty, people will be in the bamboo tube filled with gunpowder, the gunpowder behind the bar there is a small "directional stick", lit on fire tube Huoxiao,
Caused by the rapid combustion of gunpowder inside the barrel, resulting in forward thrust, so that flying bombing enemy positions, it is the world's first gunpowder rockets. And later the invention of firearms and guns, which are made of raw bamboo-tube tubular firearm which was the ancestor of modern guns.
       唐朝末年，火药开始应用到军事上。人们利用抛射石头的抛石机，把火药包点着以后，抛射出去，烧伤敌人，这是最原始的火炮。后来人们将球状火药包扎在箭杆头附近，点着引线以后，用弓箭将火药射出去烧伤敌人。还有把火药、毒药，再加上一些沥清、桐油等，捣在一起做成毒球，点着以后，用弓箭射出，杀伤敌人是后来的“万人敌”。到了宋朝，人们将火药装填在竹筒里，火药背后扎有细小的“定向棒”，点燃火管上的火硝，引起筒里的火药迅速燃烧，产生向前的推力，使之飞向敌阵爆炸，这是世界上第一种火药火箭。以后又发明了火和，这些都是用竹管制成的原始管形火器，是近代炮的老祖宗。
 (三)Papermakingangelababy拍的电影
        Paper-making technology, the invention of the Chinese nation to world civilization, one of the outstanding contributions.
(三)造纸术
李小璐的胸部    造纸技术的发明，是中华民族对世界文明的杰出贡献之一。
In the 2nd century BC, the early Western Han Dynasty have been made of paper. Is the Eastern Han period, the rumor was invented by Cai Lun. However, archaeologists have found the earlier paper.广东2019高考分数线
      公元前2世纪西汉初期已经有了纸。是东汉时期，传言是蔡伦发明。但是考古专家已到更早的纸。 
    Yuan-Xing Han Teijin first year (AD 105), Cai Lun in the manufacture of silk crystal summing up the experience of their predecessors, based on the invention of using bark, broken fishing nets, rag, hemp as a first-class raw materials, manufacturing has become suitable for writing The plant fiber paper, only to make paper become widely used writing material. Known as the "Caihou paper."
  东汉和帝元兴元年(公元105年)，蔡伦在总结前人制造丝织晶的经验的基础上，发明了用树皮、破渔网、破布、麻头等作为原料，制造成了适合书写的植物纤维纸，才使纸成为人们普遍使用的书写材料。被称为“蔡侯纸”。
  Cai Lun only improved the papermaking is improving, he wasn’t the inventor. The world's first paper is an Egyptian papyrus, and the European Middle Ages are commonly used in parchment, these two papers because the materials a single, limited room for improvement was the use of the plural types of materials, replaced by Chinese paper.