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Gauging longitude at sea became practical with the invention of the marine chronometer in the 1700s. Aside from having a chronometer appear earlier through the adoption of one of the development attempts is there any other way to have longitude determined at sea more or less reliably before the 16-1700s?

I've read that Galileo and Halley proposed celestial observation to gauge time, but these require telescopes which weren't much chop until the early 1600s and aren't very good on a rolling, pitching ship. What about water clocks or something, or a combination of other methods which would be considerably better than dead reckoning?
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