Metallurgy and Agriculture
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 BCE). 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-era 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 BCE, 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.
Other articles related to "metallurgy":
... of Toronto for outstanding work in Canadian Metallurgy 1928, awarded the James Douglas Medal for Metallurgy by the American Institute of Mining and ... distinguished service to Canada through exceptional achievement in the field of mining, metallurgy, or geology 1961, Blaylock Creek was named in his honour ...
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“In past years, the amount of money that has had to be been spent on armaments, great and small, instead of on productive industry and agriculture and the arts, has been a disgrace to all of us in every part of the world.”
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