how a clockmaker solved longitude

How I got here

Started with

Why was longitude so hard to find at sea?

Ended at

Lunar distance (navigation)

The Trail

1. “longitude problem explained” (google.com)
2. Longitude (en.wikipedia.org)
3. Scilly naval disaster of 1707 (en.wikipedia.org)

   four warships wrecked because they didn't know where they were

4. Board of Longitude (en.wikipedia.org)
5. John Harrison (en.wikipedia.org)
6. Marine chronometer (en.wikipedia.org)
7. Lunar distance (navigation) (en.wikipedia.org)

   the astronomers' competing solution

What I came away with

Latitude you can get from the sun or stars, but longitude needs you to know the time at a reference point. A pendulum clock is useless on a rolling ship, so Harrison spent decades building sea clocks accurate enough. H4 lost only seconds on a voyage to Jamaica.

Keep going

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