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

This title is Neil Armstrong's beautiful introductory analogy of what this entire book is about, the true story of longitude, "a fascinating tale of a remarkable achievement in timekeeping and navigation." Latitude, that is, the determination of north-south position, had been simple and reliable for centuries, but a simple and reliable method for finding east-west (longitude) had been difficult, well into the 1700s. The longitude problem persisted, and as empire's growth and security demanded increasingly efficient maritime navigation, the British Crown in 1714 offered a £20,000 prize to the man who could find a method for reliably and reproducibly determining it. An elaborate and complicated system involving lunar observation came about, but was laborious and calculation-intensive. Then came John Harrison, the dedicated genius who devised the first seagoing chronometers (this is origin of the word). He solved the problem, but personal rivalries, scientific steadfastness (more correctly pigheadedness), and the vagaries and idiocy of bureaucracy kept him from his rightful prize and recognition for far too long. This is the story that Sobel tells. It reads very easily, so for any who might be intimidated or fear this book is a nonstop chronicle of lofty scientific jargon and notation, don't be. The story flows well, and Sobel explains those subjects that require it, so no reader will be left behind. As written, this book struck me as being very much like the outstanding old British Connections TV show, shedding light on a specific and apparently finite historical issue, but then showing the myriad fascinating, radiating spokes of the famous and infamous. Isaac Newton touches on this story, as does Darwin, Captain Cook, King George III, Mason and Dixon (of the very famous Line), and even the notorious Captain Bligh. But what exactly is the relevance of telling this story of a fundamental navigational problem that was solved over 200 years ago? In the era of GPS telling us how to drive the SUV three miles to the grocery store, how does this story continue to carry meaning? I wondered this going in, as I picked up this book on the hearty recommendations of colleagues. The answer comes immediately (and I won't spoil it), before Sobel even begins, with Neil Armstrong's surprisingly good introduction. It's hard to picture a man who would take years to build a single clock. The cable channels give us how-it's-made shows showing automated factories cranking out identical products to the tune of 100,000 per day, and it took Harrison five years to craft his first sea clock, just one device. The others, even with his growing experience and expertise, took even longer. This is testament to a man of patience, and a meticulous one at that (one of Sobel's asides is Harrison's writing style, with and an introductory sentence that runs on for 25 pages). Harrison's story also is testament to a world with no electricity, no instant communications, no television or Internet, where literacy remained the domain of the upper classes, and where there was precious little to do with non-work day unless you had a consuming passion. Sobel tells of selfless celestial observers dedicating decades of their lives to chronicling the positions of the sun, moon, and stars; their tedious devotion empowered the Western Hemisphere for rapid colonization, setting the stage for the Industrial Revolution, mass communication, and ironically the global marketplace. I found myself about halfway through the book taking note of what is NOT present in Sobel's book. This book is missing the overdone details and asides, the too common and too-long side- and backstories that many books of this type tend toward, where the main narrative loses its way or is buried in its related stories, as interesting as they may be. This is a good thing. This tale is not just the story of John Harrison, nor is it his biography. It is the story of the longitude problem, and it encompasses many disparate people and issues, but Sobel keeps it on-task, simple, straightforward and easy to follow. If you are looking for over-detailed obsession on every aspect of the story and copious academic notation, this is not the book for you. Sobel does, however, provide an extensive source listing and an index, making this book the perfect starting point for further detailed reading or research on the subject. Bottom line: I've been to London, but there are a number of sights there I have yet to see. This story and Sobel's eloquent, fanciful, even loving descriptions of Harrison's timepieces themselves (complete with color plates showing them) has added the Greenwich Observatory to my bucket list. Sobel's simple and compelling tale of how "time is longitude and longitude time" makes me want to straddle the prime meridian, with feet in both hemispheres, and see the timepieces that changed modern seafaring, literally making possible the world we know today.

I want to prelude my review by saying that this review is what I wrote for a book review assignment in my Maritime History class at UWF. I only got a 76% on the assignment, so don't attempt to copy/paste anything out - it won't do you a whole lot of good. Having said that, I do think what I wrote is likely good enough for a customer review on Amazon. :) Hopefully you find it helpful. The Illustrated Longitude by Dava Sorbel and William Andrews is a detailed book about the development of navigation through the discovery of calculating longitude. It was first published in 1998 by Walker Publishing Company, Inc, based in New York and sells for $32.95 in the United States. This book might be considered a second edition, even though it isn't labeled as such, because the first time it was published it apparently lacked the graphs, maps, charts, etc. that are found in abundance in this edition. Miss Sorbel and Mr. Andrews set out to describe to a presumably collegiate audience how the concept of longitude was developed and how one man, John Harrison, dared to defy the scientifically biased leaders and upper societal echelon of his day by developing a method of calculating longitude based on the mechanics of a watch rather than the passage of the night sky over the horizon. And that purpose is fulfilled in this 216-page text by colorful and captivating language, intriguing ideas, and a plethora of maps, charts, graphs, and pictures. Nearly every page has some sort of illustration on it, which enhances the reading and understanding of the point the authors are trying to make. The illustrations make it relatively easy to get into the mindset of the time. Miss Sorbel did include an appropriate amount of information for college-level study. She not only has good organizational skills, which she displayed by talking about subjects in chronological order as well as categorizing topics, but she did put that extra effort in to include as much detail about the history as she could. Her bibliography is as detailed as the text of the book itself and gives her work credibility. Looking at her bibliography, one can see that she uses contemporary sources as recent as 1996, as well as sources dating back to 1808. Using the newer sources shows that she is building upon the research and ideas of modern knowledge and thinkers; using the older sources gives her information, which is from a closer time period and mindset to when the events described actually took place, more authenticity. It is also refreshing to see her extensive use of maps, charts, graphs, etc. As was mentioned before, they are placed on nearly every page and they absolutely enhance the comprehensibility of the material. Without those images the things being described, whether they be maps or charts, astrolabes or compasses, time pieces or just a portrait of an individual being discussed would be nothing more than an abstract idea with nothing concrete to attach that idea to. Without a doubt, Dava Sorbel and William Andrews created a text worth reading. The Illustrated Longitude is full to the brim with interesting facts and an amazing history on a topic that many might not even realize is interesting until reading this book. But, with a colorful use of the English language, a detailed inclusion of historical data and a topic that inspires the imagination, this text is more than interesting. And, at only $32.95 it is less expensive, by as much as ten times, than the standard college text book.

This is a great read. The book is highly entertaining as well as being very informative. Dava Sobel makes a complex subject, the measurement of longitude, come alive. The story is not only that of a scientific and technical quest, but also of human conflict, told with great skill. It begins with the concept of longitude, why knowing ones longitude was critical and how it was treated prior to the seventeenth century. The key to longitude was time, or rather knowing the time of an event, at your location and at a reference location. The two primary methods to do this are via the use of a very accurate timepiece or through the use of a knowledge of the position of the moon relative to the sun and stars, both of which I discuss this in a bit more detail at the end of this review. The problem of an accurate longitude measurement was so critical that the British Government created a £20,000 prize for the solution to this problem. Most of this discussion is about John Harrison, a carpenter and self taught clockmaker, who developed a timepiece that was accurate enough to be used to measure longitude, and the British Royal Astronomers, primarily Nevil Maskelyne, who favored the method based on the position of the moon. The book discusses Harrison's creation of marine timepieces (chronometers) that were accurate enough to solve this problem and win him the prize, and the astronomers, primarily Maskelyne, who favored the moon position method and thus sought to discredit the clock approach and deny Harrison the prize. My only reservation about the book is that there is very little technical information about exactly how Harrison's chronometers operated. There is one figure showing an escapement mechanism and a very brief discussion of how he solved lubrication and temperature problems, but I did not feel that this was sufficient to really understand how his clocks worked. Thus, I feel that a serious student of clocks would likely to be disappointed in the technical aspects of the book. However, a more general reader like myself could overlook this deficiency and focus of the human aspects of the book. I was able to find enough technical information about the operation of watches from the Internet to satisfy my needs, so the lack of this level of detail did not cause me to downrate the book from 5-stars. THE MEASUREMENT OF LONGITUDE - The simplest event to use to determine longitude is high noon, the time when you sun reached its highest point in the sky. If you had a watch set to 12noon at a reference location you could know your longitude based on the time, on this watch, that you locally observed high noon. For instance, if this watch was set so that it registered noon at Greenwich England (the location of the Royal Observatory), and you saw the sun reach it highest point at 1 o'clock, then you knew that you were one hour west of Greenwich. Since a day (one complete earth rotation) is divided into 24 hours and a circle is divided into 360 degrees, each hour of difference corresponds to 360/24 or 15 degrees of longitude, or about 1000 miles at the equator. Unfortunately, in the early 18th century there was no clock that could operate on a ship that was accurate enough to yield time measurements that could be used to accurately perform this task. If the clock ran to fast or too slow, say by only one minute per day, then in 10 days it would be off by 10 minutes or 1/6 of an hour or 2.5 degrees of longitude. At the equator this corresponds to about 1000/6 or 166.7 miles, which was clearly unacceptable. Even a much more accurate clock, say one that was off by only 10 seconds per day, would be unacceptable for a long voyage. Such a clock would be off by 300 seconds in 30 days or 5 minutes, yielding an error of 1.25 degrees, or about 83 miles at the equator. In practice, two chronometers are used, one set to the reference time and one continually adjusted to 12 O'clock at local high noon. Since the local clock was continually being adjusted it did not have to be as accurate as the reference clock that was not adjusted. Using a locally adjusted clock allowed one to determine the longitude at any time of day, instead of just at high noon. Another approach was to chart the position of the moon relative to specific stars, or the sun. One could then determine the longitude by using an almanac showing the time at Greenwich when the moon was in a particular position and when it occurred locally. The local time was determined by observing high noon. This method also had limitations as it required many laborious calculations, which were subject to error, and it could not be used when the moon could not be observed. A still earlier method used the eclipse of the moons of Jupiter as the reference, but this required a very accurate telescopic measurement that was very difficult to do on a swaying ship.

After reading Sobel's "Galileo's Daughter", I feel so, so eager to read another. Anticipation nips at me to finish the other book on my stand!

This is a competent history of an important technological turning point in human history: the invention of accurate and reliable time keeping devices. What we now call a watch or a chronometer, a reliable indication of the precise time through mechanical means, is something that's taken for granted. In the 18th century, the idea of such a device was considered near the realm of fantasy. Clocks existed, but they were considered to be little more than amusing contraptions. But so what? Why was accurate timekeeping important enough to 18th century British government to offer an exorbitant prize for the creation of an accurate clock, a sort of "X-Prize" of its day? Because a national navy cannot be certain that it's sailing to its intended destination without one. Three hundred years ago, the fortunes of the great european powers were won or lost on the strength of their navies. A ship's latitude can be accurately ascertained by taking sightings of objects in the sky. However, it's longitudinal location cannot be determined by these means without an extraordinary complex series of sightings of the moon, various stars and even the moons of other planets! An accurate clock that can tell you how long you've been sailing since you left a known location solves the problem completely. But not only do you need an accurate clock, you need one that can withstand the rigors of ocean travel with its attendant rolling, pitching, and temperature and humidity extremes. This calls for a mechanical design with construction quality of the highest order, what would have been considered bleeding edge technology in the 1700s. Dava Sobel's "Longitude" is about the man who solved the problem and made accurate sailing more of a science and less of an art. There are two major parts to this story: the tale of John Harrison and his miraculous capacity for clock design and his struggles to receive his just reward from the British Government's Board of Longitude. As with most tales of technological breakthrough, there's a competitor lurking near the Great Inventor who had his own competing solution. In this case, it's the Astronomer Royal who has dedicated his career to proving that the problem of longitude can be solved through a complex and arcane series of astronomical sightings. In retrospect, his idea is obviously doomed to failure, but it took many years for Harrison's chronometers to win the day and the prize, not least because his competitor happened to be a member of the Board of Longitude, a conflict of interest on a grand scale. So while this tale is perfectly interesting and has points of human drama associated with it, it suffers a bit from a lack of detail. i felt that there must be more to the story than Sobel reveals here, but she either felt that additional detail would sink the pace of the book or the historical record simply doesn't contain enough detail to flesh things out further.

An excellent and understandable read of a challenging subject. Thought provoking as well as educational. Recommend to wide range of readers

Well written in the style of a dedicated enthusiast. The history of this process was intriguing-I am interested to know more of the later advances.

This is the story of the problem of longitude and the solving of that problem by comparison of the earth's rotation with time and how it is achieved with accurate clocks. As such, it describes the problem of erroneous, seagoing navigation and loss of lives that resulted and also includes the governmental, scientific, engineering, and social endeavors of many persons in Europe competing in various countries for the final conquest of the problem. However, the book focuses primarily on the work of the Englishman John Harrison, his difficulties and successes in achieving the best and most accurate maritime clocks at the time, the H-3 and H-4. The book ends with the progression and advancement of other innovations and production by other individuals that culminated in a still reliable and much more reasonable maritime clock value for that time. The book does not include in-depth scientific or engineering descriptions of the clocks or of their unique innovations, nor any complete illustrations of the clocks, but does include a number of pictures of the different clocks; insightful illustrations of the H-3 and H-4 clocks and temperature compensation parts for various clocks; as well as an X-ray of wood gears and illustrations of their design. It includes a few pictures of the clocks and replicas of drafted drawings and notes by John Harrison and a much later Lieutenant Commander Rupert T. Gould restoring the clocks in the 1920s through 1930's. This illustrated book also includes many images of painted portraits of persons, photo's of places, maps and images that aid in the overall understanding of the subject. I found all the images helpful to understanding the problem, innovations and final successes of persons on the quest for better maritime time. Although I would have liked to see more complete sets of drawings for both H-3 and H-4 from Harrison or Gould, maybe in the appendix with additional notes on their composition and layers and uniquely designed pieces, the title of the book is accurate in describing its own content and the book has sufficient pictures, illustrations, and description that aid in a general understanding of the clocks, so my rating is for the effort on the book (some technical/editorial errors aside) Two critiques for this 1998 version which regard the typesetting and layout is probably for the publisher: I found the spacing of the text more disruptive to regular reading. The publisher has spaced the text somewhere around 1.5 to double spacing between lines with wide columns of text, which makes the text slower to read. I suspect the spacing is to accommodate the quantity and size of illustrations, but I would prefer closer spacing between lines even if it resulted in more white space on pages. Columns of text that are narrower and also closer between lines would read more easily. Last, the paperback at this size is cumbersome and not for lap reading. At this size it needs to be a hardback. (See complaint below about hardcover listing.) --- Initially I purchased, read, and gave away to a nephew in the last year an un-illustrated hardcover book. Recently, I purchased a used, illustrated paperback via the Amazon hardback listing here on this page. AMAZON appears to have listed this as a HARDCOVER and the ISBN in the beginning of the received paperback book matches the webpage ISBN-10, so I must conclude that either AMAZON has incorrectly listed this item as a hardcover when it is actually a paperback or the publisher has two versions with the same ISBN. There appear to be two versions of the illustrated paperback: one from 1998 [ISBN 1857027140 ISBN-13: 978-1857027143] and the other from 2003 [ISBN: 0802775934 ISBN-13: 9780802775931], while the hardcover is from 1998 and does not have an ISBN on the Amazon website [ASIN: B00450V1G8]. I give 4 demerits to Amazon for probably mixing up the description and listing of the product.

緯度と経度。気にかけないと、どっちがどっちか分からなくなりそうな２つの概念だが、その歴史は大きく異なる。 緯度が分かれば南北の移動を確定することができ、北半球では北極星を起点にすることで測定が可能であり、ギリシャ時代からその方法が知られている。一方の経度は、東西の移動を確定するのに必要だが、長いことその正確な方法が確立できなかった。 長いこととは、実に18世紀の中頃である。東西のどこにいるか、場所が分かるというのは航海には文字通り死活問題であり、イギリス政府は1714年には今日の金額で数億円にも及ぶ報奨金を提示した上で、その解決を図っている。その果実は航海技術を駆使して巨大な植民地を有するに至った大英帝国につながるわけで、その影響は計り知れない。 主人公である寡黙なヨークシャーの職人であるJohn Harrisonは、経度の測定に精密な時計を作ることで解決を目指した。これは技術的な解決である。正確な時計があれば、現地で太陽の最高高度の時間を測り、これでイギリス時間との差異を出す。差異は、角度として経度で表され、これをもとに東西の距離も計算することが出来る。 しかし、イギリスのアカデミアにとって、職人の技術はエレガントではない。科学者にとっては月の動きを観測して、経度を算出するといった理論的な方法が正しい方法であり、Harrisonにすんなりとオッケーは出さない。しかし、彼らの承認なしには、報奨金も国家の認定という栄誉もないのだ。 有名な1760年〜70年のクック船長の航海までも幾度のトライアルが行われ、精密な時計という技術的な解決は最終的には認められることになるが、当初の試作品H-1からはすでに何十年もの年月が過ぎていくのである。 本書の副題には、時代の難問を解決した孤高の天才の実話とあり、この範囲では非常に面白い。ただし、正確な時間の測定と場所の測定という話は、原理は同様のまま今日まで続き、今やGPSにより携帯電話から場所が簡単に把握出来ている。時計は原子時計になり、時間の差異の比較のため、衛星間で異なる時間が流れるのをアインシュタインの相対性理論で調整する。これも一つの魅力的なサイエンスストーリーであり、本題が「経度」とあるとやはりここまで書いてないと物足りない。本書の出版からGPSの大衆化までラグがあるため、後出しジャンケンのようではあるが、今日までの繋がりまでも読みたかったという点で、星4個としたい。

Como leigo no assunto, adorei a leitura e o aprendizado. Li o livro em 3 dias, no original em inglês.

This book is really heart touching historic thriller, a great deal of scientific events happened during ancient times were explained beautifully by the author. I am very thankful to the author for this valuable gift, and this book is must read one.

Spannend und interessant

I enjoy learning more than facts about the main story. It teaches how human passions determine many outcomes of life. In addition, it is a pleasure to learn her rich English vocabulary.