John Harrison, his clocks & longitude problem

Here is a 10 minute video segment about one of my heroes -- John Harrison. Harrison was the creator of the marine chronometer which gave sailors the first reliable way to determine their longitude while at sea. People didn't trust watches and clocks as we do now and many scientists of the day sought an astronomical solution to the problem. While possible, this was extremely impractical approach to use on board a tossing ship at sea in all kinds of weather.

Harrison made a total of four marine chronometers (H1, H2, H3 and H4), each more sophisticated that the one before. Prejudice and politics kept him from receiving a large prize for solving this problem. It wasn't until he was an old man and had gotten the attention of the British king that he was officially recognized for his contributions to science, horology, and navigation.

The full story can be found in Dava Sobel's book Longitude: The True Story of a Lone Genius Who Solved the Greatest Scientific Problem of His Time.

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