page_title: Han dynasty
section_title: Metallurgy and agriculture
hierarchical_section_title: Han dynasty / Science and technology / Metallurgy and agriculture
caption_attribution_description: Français&#160;: Boucle de ceinture d'apparat, ornée d'un animal mythique et d'oiseaux.Or martelé et ciselé,époque des Han postérieurs, 1er-2ème siècle. Musée Guimet, Paris. English: Ornemental belt buckle, decorated with a mythical animal and birds. Chiseled and hammered gold, late Han period, first or second century. Guimet Museum, Paris.
context_page_description: The Han dynasty was the second imperial dynasty of China, established by the rebel leader Liu Bang and ruled by the House of Liu. Preceded by the short-lived Qin dynasty and a warring interregnum known as the Chu-Han contention, it was briefly interrupted by the Xin dynasty established by the usurping regent Wang Mang, and was separated into two periods — the Western Han and the Eastern Han, before succeeded by the Three Kingdoms period. Spanning over four centuries, the Han dynasty is considered a golden age in Chinese history, and influenced the identity of the Chinese civilization ever since. To this day, China's majority ethnic group refers to themselves as the "Han Chinese", the Sinitic language is known as "Han language", and the written Chinese is referred to as "Han characters".
  The emperor was at the pinnacle of Han society. He presided over the Han government but shared power with both the nobility and appointed ministers who came largely from the scholarly gentry class. The Han Empire was divided into areas directly controlled by the central government using an innovation inherited from the Qin known as commanderies, and a number of semi-autonomous kingdoms.
context_section_description: Evidence suggests that blast furnaces, that convert raw iron ore into pig iron, which can be remelted in a cupola furnace to produce cast iron by means of a cold blast and hot blast, were operational in China by the late Spring and Autumn period (722–481 BC). The bloomery was nonexistent in ancient China; however, the Han-era Chinese produced wrought iron by injecting excess oxygen into a furnace and causing decarburization. Cast iron and pig iron could be converted into wrought iron and steel using a fining process.
  The Han dynasty Chinese used bronze and iron to make a range of weapons, culinary tools, carpenters' tools and domestic wares. A significant product of these improved iron-smelting techniques was the manufacture of new agricultural tools. The three-legged iron seed drill, invented by the 2nd century BC, enabled farmers to carefully plant crops in rows instead of casting seeds out by hand. The heavy moldboard iron plow, also invented during the Han dynasty, required only one man to control it, two oxen to pull it. It had three plowshares, a seed box for the drills, a tool which turned down the soil and could sow roughly 45,730 m² (11.3 acres) of land in a single day.
  To protect crops from wind and drought, the grain intendant Zhao Guo (趙過) created the alternating fields system (daitianfa 代田法) during Emperor Wu's reign. This system switched the positions of furrows and ridges between growing seasons. Once experiments with this system yielded successful results, the government officially sponsored it and encouraged peasants to use it. Han farmers also used the pit field system (aotian 凹田) for growing crops, which involved heavily fertilized pits that did not require plows or oxen and could be placed on sloping terrain. In southern and small parts of central Han-era China, paddy fields were chiefly used to grow rice, while farmers along the Huai River used transplantation methods of rice production.
caption: Ornemental belt buckle, decorated with Chinese mythical creatures. Chiseled and hammered gold, late Han period.
exif: {"Image ImageDescription": "", "Image Make": "SONY", "Image Model": "DSC-H5", "Image Orientation": "Horizontal (normal)", "Image XResolution": "72", "Image YResolution": "72", "Image ResolutionUnit": "Pixels/Inch", "Image Software": "Adobe Photoshop CS2 Windows", "Image DateTime": "2007:10:29 13:35:35", "Image YCbCrPositioning": "Co-sited", "Image PrintIM": "[80, 114, 105, 110, 116, 73, 77, 0, 48, 51, 48, 48, 0, 0, 2, 0, 2, 0, 1, 0, 0, 0, 1, 1, 1, 0, 0, 0]", "Image ExifOffset": "296", "Thumbnail Compression": "JPEG (old-style)", "Thumbnail XResolution": "72", "Thumbnail YResolution": "72", "Thumbnail ResolutionUnit": "Pixels/Inch", "Thumbnail JPEGInterchangeFormat": "866", "Thumbnail JPEGInterchangeFormatLength": "6821", "EXIF ExposureTime": "1/6", "EXIF FNumber": "7/2", "EXIF ExposureProgram": "Aperture Priority", "EXIF ISOSpeedRatings": "125", "EXIF ExifVersion": "0221", "EXIF DateTimeOriginal": "2007:09:08 16:21:29", "EXIF DateTimeDigitized": "2007:09:08 16:21:29", "EXIF ComponentsConfiguration": "YCbCr", "EXIF CompressedBitsPerPixel": "4", "EXIF ExposureBiasValue": "3/10", "EXIF MaxApertureValue": "3", "EXIF MeteringMode": "Spot", "EXIF LightSource": "Unknown", "EXIF Flash": "Flash did not fire, compulsory flash mode", "EXIF FocalLength": "121/10", "EXIF FlashPixVersion": "0100", "EXIF ColorSpace": "sRGB", "EXIF ExifImageWidth": "1984", "EXIF ExifImageLength": "1417", "Interoperability InteroperabilityIndex": "R98", "Interoperability InteroperabilityVersion": "[48, 49, 48, 48]", "EXIF InteroperabilityOffset": "740", "EXIF FileSource": "Digital Camera", "EXIF SceneType": "Directly Photographed", "EXIF CustomRendered": "Normal", "EXIF ExposureMode": "Manual Exposure", "EXIF WhiteBalance": "Auto", "EXIF SceneCaptureType": "Standard", "EXIF Contrast": "Normal", "EXIF Saturation": "Normal", "EXIF Sharpness": "Normal"}