Identification

• The magnetic needle floats upon an axis, inside a compass apparatus, to easily align with the earth's magnetic pulls.
  
  

History

• The compass was invented in the second century in China. It was first used to align structural and building elements with the environment.
  
  

Time Frame

• It wouldn't be until the 11th century that the compass was used for navigation. The first navigational compass produced by China consisted of a bowl of water with a floating magnetic needle.
  
  

Significance

• In 1282, Al-Ashraf of Persia was the first to be recorded as using a compass for study of astronomy.
  The astronomical compass would be further developed using the earth's magnetic pull and a time-keeping mechanism to calculate the direction of Mecca for the obligatory Islamic prayers. It also acted as a timekeeper that indicated the time of the five daily prayers.
  
  

Function

• Besides navigation, the compass is used in building and construction for marking landmarks and borders, and to measure horizontal lines and vertical lines for maps.
  The compass is a valuable tool used in the U.S. military, as well as in mining to assist in underground navigation.