Mechanical devices, including tractors and implements, used in farming to save labour. The great variety of farming devices covers a wide range of complexity, from simple hand-held implements used since prehistoric times to the complex harvesters of modern mechanized agriculture. From the early 19th century to the present, the chief source of power in farming has changed from animals to steam power, then to gasoline, and finally to diesel. In developed countries, the number of farmworkers has steadily declined in the 20th century, while farm production has increased because of the use of machinery.
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New Deal program to restore U.S. agricultural prosperity during the Great Depression. Established by an act of Congress in 1933, the AAA sought to curtail farm production of certain staples, in order to raise prices. It also established the Commodity Credit Corp., to make loans to farmers and to purchase and store crops in order to maintain farm prices. The program had limited success before it was declared unconstitutional in 1936.
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