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Jan 1, 1040
"Iron Fish"
There are some vague descriptions in an ancient Chinese text of an "iron fish" suspended in water that point south. Probably a magnetized metal of some sort. -
Period: Jan 1, 1040 to Jan 1, 1044
Earliest reference to a magnetic direction-finding device for land navigation is recorded in a Song Dynasty book
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Jan 1, 1088
Chinese writing describes the process of magnetizing a needle to point south
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Period: Jan 1, 1187 to Jan 1, 1202
First recorded use of compass In Europe
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Jan 1, 1232
Earliest reference to a compass in Persia
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Jan 1, 1300
Dry compass invented in Europe
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Jan 1, 1492
Christopher Columbus notes odd behavior of his compass during his voyage
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Italian geographers note that the Earth has two magnetic poles
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Edmund Halley shows the variation between magnetic and true north in the Atlantic Ocean.
1701, Edmund Halley produced the world’s first isogonic chart, which shows how the angle between magnetic north and true north varies at different points in the Atlantic Ocean. -
Bearing compass referenced in "Cyclopaedia"
Used for map making -
Liquid-filled Magnetic compass developed
Developed in the early 20th century -
GPS first used by the military
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GPS use made availabe to USA public
