From 1920’ or 1930’ till present,the agricultural production tools in Yanshan County,Hebei Province,has gone through three stages of development within eighty years more.From the traditional animal-power and hand-work to both animal-power and mechanical power use,and then to mechanical power tools as the main part for the gricultural production,significant changes have taken place,and all this became a miniature of gricultural production tools changes in China’s vast rural areas.
