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by arnarbi 3448 days ago
My favorite is "log", named after logbooks. Logbooks have maritime origins, where the ships speed is recorded. Even today, speedometer on ships are in many languages called "a log" since the original method consists of throwing an actual log overboard with a string attached to it. The string would have knots with regular intervals. To determine the speed, you count how many knots pass through your hand in a certain time.
2 comments

And I suppose that's also the origin of measuring speed in "knots" (?)
Yes

Update: my original answer was short because, well, I'm a sailor. But for more, see: https://en.wikipedia.org/wiki/Knot_(unit)

Yep. For scale: if you count for one minute, a knot every 30m or so on the string will give you your speed in nautical miles per hour (=knots)
> To determine the speed, you count how many knots pass through your hand in a certain time.

But how did they count "a certain time"? (Before stopwatches).

The origins of precise clocks is because ships needed to calculate how far they had travelled in terms of longitude (eastwast/westward. How far you've travel north/south is easy to calculate by how high the sun goes).

The British crown established an award for whoever could come up with a precise clock of this reason, it's a fascinating story, I recommend the book "Longitude: The True Story of a Lone Genius Who Solved the Greatest Scientific Problem of His Time" by Dava Sobel.

Also if you're interested in inventors from the late 17th Century, I highly recommend: "The Man Who Knew Too Much: The inventive life of Robert Hooke"
Sandglasses were around for a long time.
Well, we assume it was a long time but maybe sandglasses were really inaccurate.
I'm not sure if it would matter if they were really inaccurate if the ship used the same sandglass and rope. I've read about the shipping log -> world map work [1] where it details that the speeds/distances for a given group of boats had different errors which the gentlemen developed a technique to resolve.

[1] https://priceonomics.com/a-map-of-the-world-made-from-shippi...

Mechanical pocket watches or ship's clocks. They were expensive but accurate enough.