Introduction of Compass Car:
It is said that compass car was invented about 5000 years ago. Emperor Hwang created the compass car to indicate the direction and control the army in the heavy fog when fighted with Chi You. Besides, Chou Kung had ever manufactured the compass car 3000 years ago to guide the Yeh Shang's ambassadors home who came to china to send presents in honor of the emperors. According to the history, the compass car was invented by Chang heng in the Hang Dynasty at A.D. 120. Thereafter, Ma Chuen in the Three State which divided China from A.D. 222-265 and Yai Su in the Song Dynasty had made it, too. The method of the manufacturing is recorded totally in the history. Instead of using magnetic components, it applies the principle of different gears to let the wood man point to a fixed direction, and is a pointing device of combination of mechanism.
It sure is a great important ancient invention, and leads to a great succeeding development on the technique of structure and Mechanism.