The Anticothera Mechanism

The anticothera mechanism was able to predict the future movements of heavenly bodies like the sun and the moon. It managed the different time ratios between these these moving objects in the heavens by the use of gear ratios. The earliest evidence for the knowledge of toothed gears probably goes back at least as far as the greek mathematician and inventor archimedes, who lived in the third century b c. But he also cites artifacts from ancient china that may indicate knowledgeof gears even farther a than that.