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Before satellites, accurate clocks (vital for navigation) and accurate maps of longtitude and latitude early sailors used 3 basic techniques these were:
Dead reckoning or DR - in which one advances a prior position using the ship's course and speed. The new position is called a DR position. It is generally accepted that only course and speed determine the DR position. Correcting the DR position for leeway, current effects, and steering error result in an estimated position or EP
Celestial navigation - involves reducing celestial measurements to lines of position using tables, spherical trigonometry, and almanacs.
Pilotage - involves navigating in restricted waters (in sight of land) with frequent determination of position relative to geographic (the big hill over there) and hydrographic (shallow or deep water) features
See: http://en.wikipedia.org/wiki/Navigation
they are dead I reckon.----lol-lol