中国国四大发明的介绍课件

中国的四大发明

TheFourGreatInventions

ofchina指南针的发明是我国劳动人民，在长期的实践中对物体磁性认识的结果.IntheSongDynasty,ShenKuodescribedthefloatingcompass,suspendedinwater,atechniquewhichminimizedtheeffectofmotionontheinstrument.Thisenabledthecompasstobeusedforseanavigationforthefirsttime.Theinventionofthecompasspromotedmaritimeundertakings,anditsusesoonspreadtotheArabworld,andthencetoEurope

1.指南针是用硝石、硫黄和木炭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”。TheinventionofgunpowderwasnodoubtoneofthemostsignificantachievementsoftheMiddleAgesinChina.Thecorrectprescriptionformakinggunpowderwithnitre,sulphurandcarbonwasprobablydiscoveredintheninthcentury.Infact,inhisbook,GeHonginthethirdcenturyrecordstheproceduresformakingakindofmixturethatcouldbeignited.AftertheTangDynasty(618-907),thingstookamuchfastercourseasgunpowderwasalreadyusedinsimplehand-grenadeswhichwerethrownbyacatapult.In1126,LiGang,alocalofficial,recordedhowheorderedthedefendersofthecityofKaifengto"firecannons"attheinvadingNuzhentribalpeople,inflictingheavycasualtiesontheinvaders.2.火药东汉和帝元兴元年(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、麻头等作原料，制造成了适合书写的植物纤维纸，才使纸成为普遍使用的书写材料。被称为“蔡侯纸”。Chinawasthefirstcountryintheworldtomakeproperpaper.PapermadeduringtheWesternHanDynasty(202BC-16AD)hasbeenfoundinGansuProvince,Xi'anandotherplacesinShaanxiProvinceaswellasXinjiang.AfurtherdevelopmentofpaperiscreditedtoCaiLunoftheEasternHan(25-220).Heusedplantfibersuchastreebark,bitsofrope,ragsandworn-outfishingnetsasrawmaterials.In105,CaipresentedthefirstbatchofpapermadeunderhissupervisiontotheHanemperor,whowassodelightedthathenamedthematerial"MarquisCai'spaper".EasternHanDynastypaperfoundinWuwei,Gansu,in1974carriedwordswhichwerestillclearlydecipherable.Thin,soft,andwithasmoothfinishandtighttexture,thispaperisthemostrefinedandoldestpaperdiscoveredtodate3.造纸术开始于隋朝的雕版印刷，经宋仁宗时的毕升发展、完善，产生了活字印刷，并由蒙古人传至了欧洲，所以后人称毕升为印刷术的始祖。中国的印刷术是人类近代文明的先导，为知识的广泛传播、交流创造了条件。OnthebasisofprintingusingcarvedblocksintheTangDynasty,BiShengoftheNorthernSongDynastyinventedmovabletypeprintinginthe1040s,whichusheredinamajorrevolutioninthehistoryofprinting.

Bi'sprintingconsistedoffourprocesses:makingthetypes,composingthetext,printingandretrievingthemovabletypes.AccordingtoDreamStreamEssays,BiShengcarvedindividualcharactersonsquaresofstickyclay,thenbakedthemmakeclaytypepieces.Whencomposingatext,heputalargeironframeonapieceofironboardandarrangedthewordswithintheframe.Whileoneplatewasbeingprinted,anotherplatecouldbecomposed.Afterprinting,themovabletypesweretakenawayandstoredforfutureuse.Movabletypeprintinghasaveryimportantpositioninthehistoryofprinting,foralllaterprintingmethodssuchaswoodentype,coppertypeandleadtypeprintinginvariablydevelopedo