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

A short but well written book that sheds light on an almost forgotten man who changed the world. Interesting and fun to read, worth checking out.

John Harrison completes his first pendulum clock in 1713 before the age of 20. He made the gears for this out of wood which was radical for such a use, but as a carpenter, perhaps not to him---which is a mark of genius, I'd say; to reach beyond accepted norms in this manner. This he did after borrowing a book on math and the laws of motion; which he copied word for word, making his own copy. He incorporated different varieties of wood into his clock for strength and later invented a bi-metal pendulum to counteract the expansion and compression of various individual metals. He also employed friction-free movements so as to do away with problematic lubricants. When intrigued by the puzzle of time at sea and the issue of longitude he contemplated substituting something not prone to gravity, as a pendulum of course is, to track times passing. In 1737 he creates a cantilevered clock 4 foot square. This the longitude board (which had offered a cash bonus to anyone who could devise a method in which time at sea could be kept) admired. Four years later he returns with an improved model; then starts on a 3rd model, like the previous two, also a fairly large sized clock.But there exists a problem within this book: An artisan freemason by the name of John Jefferys at the Worshipful Company of clockmakers befriends Harrison and then later presents to him a pocket watch in 1753. Then in 1755, while still working on his 3rd model, Harrison says this to the Longitude board: I have..."good reason to think" on the basis of a watch "already executed that such small machines[he's referring to pocket watches] may be of great service with respect to longitude." He then completes version 3 in 1759. His fourth version appears just a year later, however, and is a 5 inch wide pocket watch! The obvious inference made by the author is that after he received the pocket watch from Jeffreys he seemingly put his version #3 on the back burner and soon started on the pocket watch 4th version. The author does not claim Harrison copied anything from the Jeffreys model, but she certainly phrases this section so as to lend one to believe that this may have been the case; that Jefferys had a hand in the masterstroke invention Harrison eventually produced in version #4. This is not true. Harrison commissioned the watch he received from Jeffreys and was based on Harrison's specifications. It seems that Harrison simply asked Jeffreys to test an idea which he himself hadn't the time to attack just then; as he was still working on his 3rd version of a table-top prototype clock. Hence Harrison's above statement to the board in 1755 whence his ideas were validated by Jeffreys. In addition, the author plays up the part of the Astronomer Royal's part in attempting to impede Harrison from convincing the longitude board of the efficacy of a time-piece solution to this problem over a celestial answer to this conundrum. The author also jazzes up the issue of whether Harrison received the prize the board promised to pay for a successful solution herein; even though the board supported him for upwards of 20 years as he pursued this quest. It's as if the author intentionally omitted some facts (that the Jefferys was a Harrison commission), and pumped up others (of a rival/foil on the board trying to impede Harrison and the compensation issue; implying that Harrison was jipped) just to make the story more compelling. John Harrison's story, however, is extremely compelling as it is and didn't need this extra spice served up by the author.Do read this (very short) book on how this Mr. Harrison solved the problem of knowing where one is when at sea; and if you're in London, visit the Old Royal Observatory and the Clockmakers museum (in the Guildhall) where you can see Harrison's wonderful creations in person. Enjoy!

What do Galileo and John Harrison have in common? They both had run-ins with bureaucracies that impeded the acceptance of their breakthrough ideas. And they are both subjects of books by Dava Sobel. Longitude is second book by her that I have read, the other being Galileo's Daughter. As with the latter book, Sobel combines the science of the times with a lot of background on the politics and religion of the age. She weaves these together into a coherent story that is entertaining and informative. I had never even considered that there was a ever a problem in determining longitude, so this book opened my eyes. The book I had purchased contained color illustrations that helped bring the devices that are the subject of this book to life (more can be found at http://www.portcities.org.uk/london/server/show/ConNarrative.132/chapterId/2685/Greenwich-and-the-story-of-time.html). These devices were one inventor's way of solving the problem of determining longitude at sea. Sobel covers her topic with a great deal of sympathy. Indeed, the blatant way in which the establishment hampered Harrison was very frustrating, meaning that the writing was very compelling. Interestingly it speaks to Kuhn's The Structure of Scientific revolutions, which pointed out the great steps forward in science can be accomplished by those newer to the field and that science doesn't really change until the older generation passes. I recommend this book to anyone interested in boating or science or anyone who uses a GPS device to have an appreciation for how difficult travel used to be.

One of the most pressing issues for early sailors was the problem of longitude. Because it was impossible to determine longitude, many ships and sailors died. Also, captains used the same routes as pirates or enemies of the state, which made it easy to lie in wait for your next victim. In 1714, English Parliament passed the Longitude Act which created an award for the first person to accurately determine longitude. Longitude, by Dava Sobel, explores the work of John Harrison, the man credited with accurately determining longitude for ships at sea.

Contents:
Acknowledgements
Foreword, Neil Armstrong
Chapter 1: Imaginary Lines
Chapter 2: The Sea Before Time
Chapter 3: Adrift in a Clockwork Universe
Chapter 4: Time in a Bottle
Chapter 5: Powder of Sympathy
Chapter 6: The Prize
Chapter 7: Cogmaker's Journal
Chapter 8: The Grasshopper Goes to Sea
Chapter 9: Hands on Heaven's Clock
Chapter 10: The Diamond Timekeeper
Chapter 11: Trial by Fire and Water
Chapter 12: A Tale of Two Portraits
Chapter 13: The Second Voyage of John Cook
Chapter 14: The Mass Production of Genius
Chapter 15: In the Meridian Courtyard
Sources
Index

Today, ships have GPS to tell them where they are on the seas. But before John Harrison created his first sea worthy clock, sailors were pretty much lost at sea as soon as they lost sight of land. Watches were not accurate and clocks worked on a pendulum, which didn't help on a rolling sea. Sobel weaves an interesting tale of John Harrison, a carpenter turned clockmaker, who created an extremely accurate clock for determining longitude. But this story isn't solely about Harrison. There are others that are attempting to do the impossible as well, using the heavens to find longitude. Harrison must battle prejudice, and himself, to get his timekeeper judged for the prize (£20,000 is the award). In the end, Harrison developed several chronometers, extremely accurate and able to withstand the seas and weather, that by the 1780's all log books had an entry for longitude readings by timekeeper.

This is a topic that many may not find interesting. But Sobel hasn't written an academic dissertation on the subject, she has created a highly engaging study of a man dedicated to solving one of the greatest issues facing the world at the time. Her writing style makes this an easy book to read, as there are few technical details. However, for those that need more information, she provides a rather detailed source listing. I found the book to be a fascinating look at early sailing and the answer to a problem that plagued those sailors. Also, the background on Harrison adds to the story. While he worked as a carpenter, his knowledge of wood aided him in his quest for an accurate timekeeper. His chronometer was accurate to less than a second, in the 1700's, when other, more learned clockmakers could only be accurate to 15 minutes a day (plus or minus).

This is a very good, enjoyable book on a fascinating subject.

Dava Sobel's Longitude manages to be both entertaining and enlightening. It's hard to imagine a book based on such a taken for granted historical landmark could prove to be such a good read. Personally, I must to confess a preference for historical issues, and John Harrison proved to be an engaging figure if for nothing else than his single mindedness to the task at hand. He spend the larger part of his life trying to solve a single riddle, and in the process, solved many others.