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In England you can visit Stonehenge, where a mysterious collection of large stones has stood since 1,500 BC. Scientists have never discovered the stones’ purpose. However, by observing the way the sun shines between the stones, many people believe Stonehenge was used to predict the seasons and eclipses (蚀) of the sun and the moon. 
Another early method of computing was a brass calculator, which existed in Spain nearly 1,000 years ago. The machine was shaped like a human head, with numbers instead of teeth. The shape became its undoing; some people were afraid the machine was supernatural, and destroyed it. In early recorded history, calculators that used the sun, or objects in the night sky, were developed to be used on ships to explore the world beyond the Tigris-Euphrates Valley of southwestern Asia. One such device, dating from the first century, worked with a system of gears designed to track the orbits of stars and planets. These orbits became the marked routes for ships.