Chapter 1 What’s Longitude by Dava Sobel
“Longitude” is a book by Dava Sobel that tells the fascinating story of the quest to solve the problem of determining a ship’s position at sea. It focuses on the 18th-century clockmaker John Harrison, who invented the marine chronometer, a device that allowed sailors to accurately determine their longitude. Sobel explores the history, science, and human drama behind this important technological breakthrough that revolutionized navigation and changed the course of history.
Chapter 2 Longitude by Dava Sobel Summary
“Longitude” by Dava Sobel tells the true story of the quest to solve one of the greatest scientific puzzles of the age – determining longitude at sea. In the 18th century, sailors navigating the world’s oceans struggled to accurately determine their position, leading to countless ships being lost at sea.
The book chronicles the efforts of clockmaker John Harrison to create a timepiece that could accurately measure longitude, a task that had stumped astronomers and navigators for centuries. Despite facing skepticism and criticism from the scientific community, Harrison spent decades refining his designs and ultimately created a series of groundbreaking clocks that revolutionized navigation.
Through Harrison’s story, Sobel explores the intersection of technology, science, and human ambition, shedding light on the importance of precision in navigation and the impact of innovation on society. “Longitude” is a captivating and informative read that highlights the ingenuity and determination of one man who changed the course of history.

Chapter 3 Longitude Author
Dava Sobel is an American writer who has written several non-fiction books on scientific topics. She released “Longitude: The True Story of a Lone Genius Who Solved the Greatest Scientific Problem of His Time” in 1995. The book tells the story of John Harrison, an English clockmaker who invented the marine chronometer, a device that revolutionized navigation at sea by allowing sailors to accurately determine their longitude.
In addition to “Longitude,” Dava Sobel has written several other books, including “Galileo’s Daughter: A Historical Memoir of Science, Faith, and Love,” “The Glass Universe: How the Ladies of the Harvard Observatory Took the Measure of the Stars,” and “The Planets.”
In terms of editions, “Longitude” has been highly praised and is considered the best of Dava Sobel’s works. The book has been reprinted and translated into multiple languages, and has been adapted into a TV movie and a stage play. It continues to be a popular and influential book in the fields of history, science, and exploration.
Chapter 4 Longitude Meaning & Theme
Longitude Meaning
“Longitude” by Dava Sobel is a non-fiction book that tells the story of the search for a reliable method to determine a ship’s longitude at sea. It explores the history of navigation and the challenges faced by sailors and explorers in accurately determining their position on the ocean.
The book highlights the importance of longitude in navigation and the impact it had on world exploration and trade. It also delves into the scientific and political debates surrounding the issue, as well as the eventual development of the chronometer by John Harrison as a solution.
Overall, “Longitude” sheds light on the history of science, technology, and the pursuit of knowledge, while also telling a captivating story of invention and perseverance.
Longitude Theme
The primary theme of “Longitude” by Dava Sobel is the human quest for knowledge and understanding. The book tells the story of John Harrison, a self-taught clockmaker who revolutionized navigation by inventing a reliable and accurate marine chronometer. Throughout the book, we see how Harrison’s determination, ingenuity, and persistence led to a breakthrough that had a profound impact on maritime history.
Another key theme in the book is the tension between scientific innovation and institutional resistance. Harrison faced skepticism and opposition from the scientific establishment, who were reluctant to accept his new method for determining longitude at sea. Despite these challenges, Harrison remained committed to his work and ultimately proved the effectiveness of his invention.
Additionally, “Longitude” explores the intersection of technology and human experience. The development of the marine chronometer not only improved navigation and led to safer and more efficient sea voyages but also had broader implications for trade, exploration, and global interconnectedness.
Overall, “Longitude” is a story of individual achievement, scientific progress, and the enduring human quest to understand and conquer the challenges of the natural world. It highlights the power of innovation, perseverance, and collaboration in overcoming obstacles and reaching new horizons.

Chapter 5 Quotes of Longitude
Longitude quotes as follows:
1. “The true worth of man is to be measured by the objects he pursues.”
2. “The quest for longitude has been a struggle, an adventure, a drama that took years of stubborn effort and imagination.”
3. “The ocean was the enemy of time, the great barrier to trade and the swift exchange of information.”
4. “The nearest one can come to thinking with longitude is to think with latitude.”
5. “The story of longitude is the story of time, of how one great obstacle to trade and navigation was overcome.”
6. “To have gotten so close to time – at the farthest outposts of it – as to be able to feel how time beats, like a heart.”
7. “They sought longitude, the true value that fetched any price.”
8. “No one who sailed beyond the sight of land could predict his longitude, or position on the earth, with any certainty.”
9. “Longitude is what time is to space, a man’s place upon this earth.”
10. “A present was a gift for the rolls on which it rolled.”
Chapter 6 Similar Books Like Longitude
1. “The Discoverers: A History of Man’s Search to Know His World and Himself” by Daniel J. Boorstin – This book explores the history of human discovery and the individuals who have pushed the boundaries of knowledge throughout time.
2. “Longitude by Wire: Finding North America” by Richard Stachurski – This book follows the development of long-range navigation technology and its impact on the exploration of North America.
3. “Longitude by Satellite: Exploring the Earth with GPS” by Dave Turner – This book delves into the history and technology behind GPS and how it has revolutionized navigation and exploration.
4. “Longitude and Empire: How Captain Cook’s Voyages Changed the World” by Brian W. Richardson – This book examines the impact of Captain Cook’s expeditions on global exploration and the mapping of the world.
5. “Navigating the Stars: How to Find Your Way in the Night Sky” by Dr. Liz Clarke – This book is a beginner’s guide to celestial navigation and stargazing, teaching readers how to find their way using the stars and planets.
YouTube https://www.youtube.com/watch?v=IX6U_Qm60Nc
Amazom https://www.amazon.com/Longitude-Genius-Greatest-Scientific-Problem/dp/080271529X
Goodreads https://www.goodreads.com/book/show/4806.Longitude
