To quote an esteemed LC history professor on the technical difficulties of pre-modern navigational technology: "Nowadays, you'd refer to that as being lost. But they actually thought they could get somewhere." Shortly after people discovered that the world was round and wanted to sail around it, they realized that they had no way of telling how far they'd gone and how close they were to where they wanted to be, as opposed to how close they were to the Bermuda Triangle, for example, or the giant pointy sneak-attack rocks that were about to sink their ship. The kingdoms of Enlightenment Europe were basically racing against each other to find a way to calculate longitude that worked better than eyeballing the north star with a sextant on a pitching deck, which pretty much didn't work at all. Longitude is the story of John Harrison, the man who invented the first clock accurate enough to keep time at sea, allowing navigators to know exactly where they were on an East-West scale. Harrison, and the reader, get sucked into a whirlpool of royal and scientific politics, which can get very dirty. Also has a cameo appearance by everyone's favorite benignly insane monarch, George III.

Audible sale (#22 of 40) 4 hours 20 min. Narrated by Kate Reading (B)

Interesting history of the invention of a clock that would withstand all the vagaries presented aboard sailing ships that would allow navigation by calculation of the longitude of the ship once sight of shore was lost. A Goodreads review led to my discovery of this book.

Se trata de una aventura científica, y de cómo John Harrison, un humilde relojero, peleó durante décadas para resolver el problema de hallar la longitud en el globo para los navegantes. Posteriormente, este desconocido autor se tuvo que enfrentar al establishment científico de la época y reivindicar su invento frente al de otros.

Es una historia brillante, muy ligera y muy bien contado. No hace falta más para recomendar este libro.

Until reading this book, I did not know that a problem existed determining where a ship was situated longitudinally. If the sky was clear, the 'clock of the heavens' helped determine the position. If the sky was overcast, an accurate clock was needed on board. For the longest time, no accurate clock existed.

From the book:
"To learn one’s longitude at sea, one needs to know what time it is aboard ship and also the time at the home port or another place of known longitude—at that very same moment. The two clock times enable the navigator to convert the hour difference into a geographical separation. Since the Earth takes twenty-four hours to complete one full revolution of three hundred sixty degrees, one hour marks one twenty-fourth of a spin, or fifteen degrees. And so each hour’s time difference between the ship and the starting point marks a progress of fifteen degrees of longitude to the east or west. Every day at sea, when the navigator resets his ship’s clock to local noon when the sun reaches its highest point in the sky, and then consults the home-port clock, every hour’s discrepancy between them translates into another fifteen degrees of longitude."

This is the story of John Harrison who spent forty years of his life inventing a clock that could keep accurate time.

There are 15 chapters in the book, aptly named to describe the 'steps' along the way.

Exceedingly readable, this book describes the solution to the thorniest problem of its day- the longitude problem.

5 stars

I take GPS for granted. I don’t use it that much personally, because I don’t tend to go anywhere, but I’m sure all this technology I love to use makes use of GPS. Thanks to GPS, we can forget that calculating longitude without the help of a network of satellites is difficult and requires great mathematical and engineering expertise. GPS might not be great at giving directions, but that doesn’t mean you’re lost.

In the days—centuries—prior to GPS, you could get lost. Really lost. I’m not sure how to describe how lost you could be, out there on the ocean, no longer in sight of shore. Latitude was relatively easy—well, easy enough once you dealt with the pitching deck, the storms, and the scurvy. Latitude corresponds both to the sun’s altitude in the sky (at noon) and to the altitude of certain stars (if you are in the Northern Hemisphere, Polaris is a good choice) at night. So you could figure out how far away from the equator or the poles. But how far away were you from the nearest charted island? And were you to the east of it, or the west?

Longitude, or rather the “starting point” for lines of longitude, is entirely arbitrary. The only way to calculate longitude is to measure the difference in time between two points: the reference point (e.g., 0° longitude) and your current location. That sounds easy enough: just take a watch with you that’s set to London time, and at noon at your current location, check what time the watch reports.

Much like our skill at flinging sophisticated pieces of technology into orbit has advanced, so too has our ability to construct watches. For the longest time, the solution to calculating longitude eluded mariners because no one could construct a clock that was both accurate enough and durable enough. The constant changes in pressure, humidity, and temperature played havoc with the fine mechanisms that allowed clocks to keep time. Without accuracy, a watch is useless as a method to calculate longitude.

This problem consumed great minds for centuries. It eventually came to a head in 1714, when the English Parliament authorized the creation of a Board of Longitude to disperse prizes for new ways of accurately calculating longitude. The grand prize was £20,000—or $12 million in today’s currency. Longitude was a big deal.

I knew the gist of the John Harrison story prior to reading Longitude, but Dava Sobel goes beyond the accomplishments of this single man and charts the course of the problem, and all its proposed solutions. She sets up a context against which the true scope and power of Harrison’s achievement might be measured. As I explained above, the general solution to calculating longitude was long in evidence, but no one could think of a way to effect it. Galileo had some good ideas related to his observations of Jupiter’s moon, but they were hardly practical for marine navigation. Later, Newton and other English scientists were convinced that astronomy held the key to calculating longitude—and the king agreed with them, establishing the Royal Observatory for the purpose of cataloguing the stars. More than a simple puzzle that made academics scratch their heads, the problem of longitude affected society and the economy. It drove scientific inquiry and technological innovation. Watching this unfold through Sobel’s storytelling is breathtaking and inspiring.

Harrison’s origins read like something out of a fairy tale or a superhero book. His father was a carpenter, and he was trained as a carpenter, not as a watchmaker. Yet this craft fascinated him, so he trained himself to build clocks. In fact, he built a clock entirely out of wood, a clock that required no lubrication owing to the way he had constructed it and the type of wood he had used. John Harrison was not just a tinker or dabbler; he was a creative genius. So he decided to solve the longitude problem. And he did. But when he went to London for his reward, he was met with scepticism, animosity, and belligerence. Thanks to the politics of London, the Board of Longitude was populated by representatives from the astronomy camp, and they were none too keen on Harrison’s mechanical marvel. For the rest of his life, Harrison would improve upon his prototype and receive stipends from the Board, but that recognition and prize money lay beyond his reach.

I personally think we tend to put too much stock in the “great individual” approach to history. I can see why it is appealing for stories, and for works of popular history: our ability to turn history into a biography boils away our dislike of dates and dry facts and lets us focus on the relationships and motivations of the characters. The central conflict of Longitude is not the need to calculate longitude but the antagonistic relationship between the Harrisons and the Reverend Maskelyne. Maskelyne championed the “lunar distance” method of calculating longitude. It just so happened, too, that later on in his life he became the Astronomer Royal, and therefore a member of the Board of Longitude. That didn’t go over well for Harrison’s chances at being awarded that prize.

Indeed, echoes of the great rivalries across the ages surface in Longitude, reminding us that science is never as simple nor as objective as we like to think. Invention is partly innovation, partly inspiration, and part imitation. Sobel is careful to stress that Maskelyne was not the villain in this piece, merely the antagonist—like the feud between Newton and Hooke, the feud between Harrison and Maskelyne was a dispute between two men who knew their stuff. But where ego is concerned and establishing primacy is often necessary for the money and prestige that follows a discovery, tempers will flare and harsh words will be exchanged.

So with this centuries-old problem juxtaposed against a feud between a rural carpenter-turned-watchmaker and the Astronomer Royal, Sobel turns Longitude from a history book into an exciting story. The trick to making any historical account interesting lies in exposing the details and connections that a casual reader, like myself, wouldn’t necessarily know. Sobel does this by charting the connections between Harrison and luminary contemporaries, including Isaac Newton, Edmund Halley, and Christopher Wren. She does this even with the considerable handicap of lacking much evidence about Harrison’s early life.

Sobel also goes into the intricate inner workings of Harrison’s successive marine chronometers. The genesis and evolution of the marine chronometer, particularly once it had spread to other watchmakers, gave us not only an accurate way to calculate longitude but other useful horological innovations! As Sobel describes the clever devices he designed to solve the limitations of sea clocks, all I could think was, “I have no idea what she is trying to say. This book could use pictures.” Lo and behold, as I reached the middle of the volume, I stumbled into the glossy inset that includes diagrams of a grasshopper escapement and photos of Harrison’s portrait and the chronometers H–1 through H–4. It’s amazing that these timekeepers (with the exception of H–4) continue to run today.

I wish Longitude were longer, but at the same time I love the size of the book as it is. My edition is a nice little paperback copy with a beautiful, high-quality cover. It is compact and deceptively slim for such an interesting history. Yet it is also definitely just a survey. I’m not sure, given the lack of details, how much longer Sobel could have spun it out. But the episodic nature of the chapters, and the abbreviated way she communicates the stories of the testing of H–3, H–4, etc., by Captain Cook and others, seems to indicate that there is more here to tell. Or is that another story?

Oh well. I really liked Longitude. It has the perfect mix of narrative, character, and scientific explanation to make it a fascinating work of history of science. Dava Sobel weaves a fascinating tale set against a problem centuries in the solving, one that vexed astronomers, clockmakers, and mariners alike but whose solution led to advances in all three fields. I, personally, rely on my GPS devices to find my longitude. But it’s good to know that if the GPS network ever goes down, there is at least one museum I can rob for some high-quality longitude calculation devices.

Now excuse me while I draw up some blueprints….

n  n

Interesting read that details how the Prime Meridian came to be set in England and how a lone clock maker clashed with bureaucracy of the longitude commission.

"For the ocean's silence spoke a single, uniform, terrible message: 'You are lost, you are lost."

In "Longitude: The True Story of a Lone Genius Who Solved the Greatest Scientific Problem of His Time," I was taken on an exhilarating journey through the fascinating world of 18th-century navigation and the brilliant mind of John Harrison. The book, written by Dava Sobel, chronicles the extraordinary life and achievements of this lone genius who tackled the most pressing problem of his era – determining a ship's longitude at sea.

"Harrison never learned to add or multiply. Yet, using little more than sticks, pendulums, and loops of gut, he'd found a way to calculate the new day's noon as soon as the old day's was over. A day's worth of those bits and pieces would eventually add up to the only quantity that meant anything at all to him: time."

A quote that emphasizes that despite Harrison's lack of formal education in mathematics and arithmetic, he possessed an extraordinary talent for using simple tools like sticks, pendulums, and loops of gut to calculate and measure time accurately. This unique skill allowed him to devise innovative solutions that ultimately led to the creation of accurate maritime chronometers.

Sobel vividly transported me back to the Age of Exploration, where maritime trade, conquests, and scientific advancements were shaping the world. Navigational accuracy was paramount, yet the elusive concept of determining longitude plagued sailors and explorers, leading to countless shipwrecks and lost lives. Enter John Harrison, a self-taught clockmaker whose determination and ingenuity led him to create a series of groundbreaking timepieces, known as chronometers.

The narrative expertly weaves between the challenges Harrison faced in developing his accurate chronometers and the political and scientific rivalries of the time. The Royal Observatory in Greenwich played a significant role in the story, as did the scientific establishment's skepticism of Harrison's unconventional methods. As I turned the pages, I marveled at the intricacies of clockmaking and the profound impact Harrison's chronometers had on navigation. The book illuminated the relationship between timekeeping and longitude, a connection that had eluded scholars and astronomers for centuries.

This book is a captivating account of a forgotten hero, an unsung genius whose dedication and brilliance reshaped the course of history. A must read!

4 ☆

Before Britannia could rule the waves, its captains needed to figure out where their ships were going and, just as importantly, how to return home.

Sure, the concept of sectioning off the world by concentric lines of latitude (running east-west) and longitude (aligned by the poles) had existed as early as 300 B.C. The astronomer and cartographer Ptolemy had plotted in 150 C.E. his first world atlas with the Equator as 0° Latitude. Many dedicated astronomers had already witnessed that the sun, moon, and planets passed almost directly overhead at the earth's equator so Ptolemy's decision had been based on scientific observation. But for centuries, where to set 0° longitude was a political selection, so it had bounced around from the Canary Islands (Ptolemy's choice) to Rome to Jerusalem and to many more locations. Finally in 1884, representatives from 26 countries agreed at the International Meridian Conference to make the Greenwich meridian the world's prime meridian.

In Longitude: The True Story of a Lone Genius Who Solved the Greatest Scientific Problem of His Time, Dava Sobel focused on the 18th century when the British and many others (except perhaps the Polynesians - see Sea People: The Puzzle of Polynesia) were beset by maritime misadventures and tragedies. In the early 1700s, determining a ship's position was a highly imprecise and challenging process as the main method of navigation was by dead reckoning, guided only by compass and the direction of the sun's path. Sailors could reasonably determine which latitude the ship occupied but they were literally and figuratively "at sea" when it came to the question of their longitudinal location. [Sextants weren't invented until the 1730s. Even then celestial navigation would require hours of observation, nautical charts, and an accurate timekeeper.]

The continued loss of ships, lives, and cargoes finally motivated London's various shipping interests to unite in their petition to Parliament to solve the "longitude problem" (which was really a navigation problem). The Longitude Act of 1714 established the Board of Longitude as judges to determine the recipient of prize money which ranged from £10,000 to £20,000, depending on the solution's level of accuracy. According to the Bank of England's inflation calculator, the 1714 prizes would be equivalent to £1.5 to £3 million today.

Dava Sobel wrote an interesting narrative about an unlikely hero, John Harrison, who became enmeshed in a David and Goliath battle that lasted decades. Although John Harrison worked as a carpenter, his mind had mechanical inclinations. He taught himself how to make a clock before he turned twenty. Upon learning of the prize from the Longitude Act, he sought to create the perfect timekeeper, despite the ways a moving vessel with its humid atmosphere eventually rendered all contemporaneous clocks erroneous. When navigators simultaneously knew the local time aboard the ship and the time at another location which had a known longitude, then they could could calculate their ship's longitude.

The Board of Longitude consisted of government officials, naval officers, and scientists from both astronomy and mathematics. By the mid-18th century, one Board member -- the astronomer royal Reverend Nevil Maskelyne -- keenly wanted a solution that reflected his scientific discipline. In particular, Maskelyne favored the lunar distancing method. He/the Board adopted unscrupulous methods to thwart Harrison: sabotage, backstabbing, and theft of intellectual property. Maritime navigation is a technical issue, but this tale reeked of jealousy, competitiveness, and political intrigue. Nothing like money and professional glory to elicit all the ugly sides of human nature.

Be still my geeky heart because this little book (4 hours for the audiobook) touched upon maritime history, astronomy, timekeeping, and even cartography. For an esoteric topic, this story was engaging, concise, and clear. The book only lacked images.

This link shows John Harrison's first submission for consideration. Completed in 1735, the H1 weighed 75 pounds and was housed in a 4' x 4' x 4' case.
https://www.rmg.co.uk/collections/obj...

This link is for Harrison's prize-winning H4, finished in 1759. This elegant chronometer with its pretty detailing had been miniaturized down to a diameter of 5 inches.
https://www.rmg.co.uk/collections/obj...

Harrison was an inventor with a perfectionist's streak. He continued to improve his masterpiece. This link is for John Harrison and Son's H5, made in 1770:
https://collection.sciencemuseumgroup...

3.5 stars. RTC

A short popular science book that examines the invention of the chronometer, or ships clock. Not just a clock, but one that remains uneffected by the humidity, heat and cold, atmospheric pressure and of course the passage in a ship on the high seas, being thrown about. Of course, it must keep time accurately enough to be relied on for navigation, as a clock that accurately keeps time in all conditions is the key to determining longitude. The actual key was knowing the time at a known location (home port or the like) and the current location simultaneously, allowing longitude to be calculated accurately.

And so, it is more than the story of a chronometer. This book describes the circumstances in which the clock finally won out as the recognised way to accurately determine longitude. It was a close thing, with astronomers seemingly unable to allow a mechanic to be recognised where astronomy and mathematics should (in their eyes) have been the way of navigation. The lunar distance method - with sextant, tables of figures and hours of calculations and then adjustments to be made was being put forward by the astronomers as the only reliable way. There were others of course, the mystical powder of sympathy being the most quacky of them (in essence, a powder of secret origin that can heal a wound at a distance, but causes some pain in doing so - the theory proposed an injured dog would be taken aboard a ship and at predetermined times the powder would be administered to the bandages in the home port; on the ship the dog would howl, and the local time could be compared to the home port time, and calculations made to measure the longitude. (This method didn't proceed to testing)).

Overseeing the longitude problem, and able to payout the prize money of twenty thousand pounds, was the (British) Board of Longitude, made up of scientists (astronomers and mathematicians featuring heavily), naval officers and government officials. They continued to adjust the rules and the burden of proof to make it ever harder to claim the prize.

So this is the story of John Harrison, self taught clock maker and his life long development of his chronometers, that became known as the Harrison 1 (H-1 for short) in 1737, the H-2 in 1741, the H-3 in 1759, the H-4 in 1760 and the H-5 in 1770.

A good short book, sadly lacking any photographs other than the one inside the cover. I see from other reviews that a newer edition does provide the photographs, which would be a great addition. Great effort to make the very complex relatively simple.

4 stars

The book really made me empathise with the woes that John Harrison was going through in his dealings with the Board of Longitude, especially with Nevil Maskelyne. The history of time keeping in sea as well as the history of the time keeper in land does give a different picture of the 17th and 18th centuries in stark contrast with the 21st century. Yet how far science and technology have took us forward today really made me to contemplate upon the words Newton had once said "If I have seen further it is by standing on the shoulders of gaints". This literally stands true here, as if it was not for the dedicated efforts by men like Harrison & his son, George Graham, Kendell, Mudge, Arnold and a lot of others the world may never have seen such wonderful new instruments. 'Chronometer' earlier had ringed in me the memory of an instrument used in ships but now it truly makes me remember a bygone age where the quest for finding the longitude was the passion that kept a generation of men so avid and awake.

A fun and informative little non fiction book about something I knew nothing about. It's a dramatic tale, filled with neat historical tidbits. It's worth a read, especially if you have no idea about the quest to find longitude at sea!