Posted on Wednesday, November 21, 2012
By Kadri
Image Credit: Kadri Tinn

Longitude by Dava Sobel

Finished reading November 21, 2012

Rating 8/10

Do you know how to find your location on Earth? As far as I'm concerned, I could manage to find my latitude in the northern hemisphere. But this book is concerned with finding the longitude, which was a major issue in the 17th and 18th century while navigating on the sea.

There was a rather fierce competition to find a way how to find the difference in time from one location to the other. There was the option of observing the Moon's movement against the stars or Jupiter's moons. However there was also a mechanical solution - a precise timekeeper, later to be called a chronometer. The first of which was built by John Harrison. And John Harrison is who this book is really all about with some diversions to people he had to deal with - Royal Astronomer Nevil Maskelyne for example.  He seems like a regular antihero, and apparently every book on the history of astronomy depicts him as a really awful guy.

I liked this book, in part because it was short and in small format and also because it's nice to read a bit more on something that's usually just one chapter in the history of astronomy books.

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