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View Full Version : Navigation at sea, the story of longitude



bob10
9th October 2015, 10:14 PM
https://youtu.be/8zyA4qQ7EvI

austastar
11th October 2015, 09:36 AM
Hi,
An excellent story of a battle of a clever individal against the biased buffoonery of the British Naval system.
Well worth watching.

Thanks for posting it.

JDNSW
11th October 2015, 10:10 AM
Not as clear cut as is often implied. Competing with the use of time pieces to find longitude was the use of lunar departures - effectively measuring time by the position of the moon.

This became practical about the same time as Harrison's chronometer, thanks to improved predictions of the moon's position, and the only equipment it needed was the sextant that the navigator probably already had. (James Cook used this on his first voyage, the chronometers only becoming available for his second.)

Chronometers did not become cheap enough to be used by most ships until well into the nineteenth century, and many navigators were still using lunar departures as their primary method or as a backup into the twentieth century.

John

AllTerr
11th October 2015, 12:57 PM
An incorrectly logged longitudinal coordinate is what made Pitcairn Island attractive to the Bounty mutineers, and what kept them from being found for almost 20 years.