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How Sailors Found Their Way at Sea
A survey of maritime navigation history, from coast-hugging pilots and star paths to the compass, sextant, chronometer, radar and satellite positioning.
Seafaring Life and Navigation
Navigation and Instruments
The tools and methods that let ships cross open water.
Lighthouses and Coastal Beacons
How lighthouse development moved from open fires and ancient towers like the Pharos to Fresnel lenses, rock-built towers and the keepers who tended them.
Lightships and Navigation Buoys
How lightship stations and buoys marked shoals and channels where no tower could stand, from the first English lightvessel in 1731 to modern buoyage.
Mercator and the Making of Sea Charts
How the Mercator projection of 1569, Edward Wright's tables and later surveys changed Mercator sea charts and made course plotting easier for navigators.
Portolan Charts of the Medieval Mediterranean
What portolan charts were, how pilots used their compass lines in the medieval Mediterranean, and why historians still debate where and how they began.
Radar and Electronic Navigation
How marine radar, radio beacons, hyperbolic systems and satellites changed pilotage and position finding at sea from the Second World War onward.
The Longitude Problem and the Marine Chronometer
Why finding longitude at sea was so hard, how the British prize and John Harrison's timekeepers helped, and how the marine chronometer became standard.
The Magnetic Compass at Sea
How the magnetic compass reached ships from China and the Mediterranean, and how makers added the card, gimbals, liquid bowls and iron-ship corrections.
The Mariner Astrolabe and the Quadrant
How the mariner astrolabe and quadrant let 15th and 16th century pilots measure the height of the sun and Pole Star to find latitude on a moving deck.
The Sextant and Celestial Navigation
How the reflecting octant and sextant of the 1700s made marine sextant sights accurate, and how celestial navigation became a routine daily task at sea.
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