Longitude: The True Story of a Lone Genius Who Solved the Greatest Scientific Problem of His Time,   ISBN:9780802715296

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Another great read by Dava Sobel, with complex technical, political, and historical issues boiled down to their essence. Longitude is the story of the common man, self-educated and modest, who succeeded where the giants had failed. Unfortunately Harrison could have used a modern PR man to make his case, as he never did get his due credit, either in the scientific community or in the division of the royal prize money. They say the meak will inherit the earth, but that will only happen if they are not all killed first.

In the 18th century a series of naval mis-haps led the British Crown to set up a huge prize for the one who determined how to know your longitude while at sea. This had been a problem since the first days of sailing, and had gotten to be more of an issue as ships became larger and more laden with valuable export goods and trained sailors. Conventional wisdom, espoused by the likes of Sir Isaac Newtown was that the solution to the problem of the longitudes was found in the heavens. Trained navigators, equipped with telescopes and detailed charts of the stars, planets, and moons of the planets could calculate their longitude. It never really worked with the degree of accuracy that one needed to find a small island in the remote seas. Others had more innovative solutions like networks of reference cannons and lights, or dogs that yelped when stuck with a needle.

Harrison was a self-taught clock maker. He had done a few commissioned clocks, some still running today, and determined that he could build an accurate and durable clock and watch. Eventually he solved all the known issues of sea motion, temperature changes, lubrication, and accuracy to meet the royal requirements. Unfortunately he was slow to promote his ideas, often needing a decade or so to make some minor improvements. His real Achilles heal was politics, as the scientific community viewed him as a mechanic when a visionary was needed.

All in all a great read. I can also recommend Ms. Sobel's book on Galileo, titled Galileo's Daughter, which puts surviving correspondence into a fascinating historical context.

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Someone has finally written the story of Harrison and his chronometer into a nice, readable story. Longitude is a good little book outlining the problem sailors faced in determining their longitude and the mechanical genius behind its resolution. Sobel's telling takes the reader through the nature of the problem, which is probably unfamiliar to most today, and illuminates the innovations achieved by John Harrison, a relatively unschooled but brilliant man gifted in mechanics and engineering. The problems he faced from his competitors and from the Longitude Board, essentially judges for the awarding of the prize to whoever found a workable solution, are very interesting. The tale is full of conflict-of-interest problems, engineering hurdles, and egos. I was fascinated with the longitude problem before reading this book and am now more fascinated in its history. This is a good book that is well written and will wet the appetite for more.

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In 1714, tired of losing ships and sailors by having them smash into shorelines to sink and drown, England passed the Longitude Act, offering a significant reward to the man who could properly determine the exact position of a ship at sea. The Act was a bust. For fifteen years the five member Longitude Board never met simply because it never received a credible idea to consider. But when completely unknown John Harrison collared Board Member Edmund Halley, Halley is so impressed that he forwards Harrison to well known clock maker George Graham. Amazingly, after some serious jawboning, the village carpenter, Harrison, leaves the Fellow of the Royal Society, Graham, with a generous loan to be repaid at no great haste and at no interest.

John Harrison solves the problem of longitude. As with any breakthrough discovery though, there was much resistance and entrenched opposition. The idea that a village carpenter understood time and the earth's rotation better than the most learned minds of his age, that the conundrum called longitude could be solved by mechanics as opposed to celestial mapping, was anathema. Harrison would have to overcome much prejudice just to get to sea trials. But on his first voyage to Lisbon and back Harrison proves a sixty mile error and his journey, detailed in this excellent work by Dava Sobel, begins.

This is an altogether delightful read, one that will make you smile.

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This short book is a fun and interesting read about how John Harrison revolutioninized the timekeeping industry and in the process solved the longitude problem. The longitude problem is the name given to the inadequacy in determining a point's longitudinal coordinate (east-west coordinate). The beginning the book goes a lot into this problem and that was the highlight for me. It turns out determining the latitudinal coordinate is well known. It was surprising to me to find out how difficult it is to know one's position on earth. The stars help but only so much.

Well there were different attempts to determine the longitude. The most widely expressed were those that used celestial bodies. The precision of these methods were not great and depended on such celestial bodies being visible.

The basic problem is that one must somehow measure the distance from some known location. If it's noon in England when I set out west, I can determine my distance from the starting point by comparing the relative time difference in my new noon and England's noon. So if I leave England at noon and travel west and then x hours later it is noon wherever I am, then I can determine how far I have traveled (this is possible because the earth's rotational speed is constant). Now the problem is having a precise enough timekeeping device. John Harrison's contribution was to engineer a much more precise clock than had been developed previously.

I thought the subtitle of the book was misleading. Was the longitude problem really the greatest scientific problem of the day? No new science was devised to solve it. It was simply an engineering feat - an impressive one to be sure but not exactly a new paradigm of science.

The end of the book is not nearly as good as the beginning. A lot of effort is expended on the various versions of the timepiece created by Harrison. Gets a little boring.

Overall an interesting book and especially a good read for someone interested in the history of science, timekeeping, and navigation.

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I read this book on the strength of Tyler Cowen's recommendation. He called it "fascinating," and that was enough of a recommendation for me.

It's nonfiction: the story of how Westerners finally solved the problem of calculating a ship's longitude while at sea. Not knowing how to do this with much precision had been causing countless shipwrecks and delays for hundreds of years.

Dava Sobel begins by discussing the problem and giving examples of the many mishaps ascribable to humanity's ignorance in this area. Then she discusses many of the kooky solutions, some unassailable in theory but impractical for ships at sea. These include wounding dogs, firing cannons, and even calculating longitude based on the regularly recurring eclipses of Jupiter's moon.

Watching humanity trying to solve this problem is inspiring, but a real solution had to wait until the invention of a completely reliable timepiece, the story of whose creation takes over as the subject of the book about halfway through. See, if you know the exact time (based on the sun) on ship at sea, and you know what time it is back home in Greenwich, you can infer how many arcs of distance you have traveled.

Alas! I didn't think the book was as fascinating as Mr. Cowen did. Part of the problem is that unless you're a mariner cum physicist cum astronomer, there's going to be scientific aspects of Sobel's tale that are going to be over your head, as was the case for me. She smugly assumes you're not only familiar with basic astronomy but also are fully conversant with nautical terms. Here's a sample:

"Before the Back-Quadrants were Invented," the pamphlet states, "when the Forestaff was most in use, there was not one Old Master of a Ship amongst twenty, but what Blind in one eye by daily staring at the Sun to find his Way." (p. 43)

And there's a lot of affectation sprinkled throughout the book. Each chapter starts with pretentious and irrelevant snippets of verse, for example.