Zu Chongzhi (429 -500), was a great scientist living between Song and Qi during the Southern Dynasty. His contribution to mathematics was the calculation of the circumference ratio. He figured out seven significant figures after the decimal point, leading the whole world for over a thousand years. In terms of astronomy, Zu Chongzhi created the Daming Calendar and the method of measuring time in winter solstice. In addition, he also invented rice-polishing device using water power, compass chariot, thousand-mile ship, and so on.