The first significant revolution in Chinese agricultural technology occurred when iron agricultural implements became available to the Chinese peasantry. The earliest iron plow found in northern Henan dates from the Warring States period (475–221 bce) and is a flat V-shaped iron piece that must have been mounted on wooden blades and handles. It was small, and there is no evidence that draft animals were used. Cattle-drawn plows do not appear until the 1st century bce. Several improvements and innovations, such as the three-shared plow, the louli (plow-and-sow) implement, and the harrow, were developed subsequently. By the end of the Song ...(100 of 27369 words)