Most of my life, I was continually confused over the definitions of longitude and latitude. As an elementary school student, I thought of the earth as simply being measured by a ruler or yardstick, or straight up and down. Therefore, longitude seemed logically (or illogically in this instance) as measuring the earth’s length, which is, of course, the north-south measurement or latitude, instead.
This confusion followed me for years. (Along with my lifelong dysfunction differentiating my left from my right, I might add. I drive Gerry crazy when I am instructing him in the car. “No, no! My other right!”)
My troubles with longitude and latitude finally ended over a decade ago when I was present when Joan Dash received the Boston-Globe Horn Book Award for non-fiction in 2001 in Boston for her book “The Longitude Prize.” This most-prestigious award is given in the categories of picture books and non-fiction and literature for children and young adults.
Dash’s book was published in 2000, and I hadn’t, as yet, read it. Her acceptance speech was intriguing, and I was impatient to read the story John Harrison and the quest for a method of determining longitude. Although her book was written for older children, or young adults, the subject by nature is technical and thorough. Dash’s book won several other prizes, and it makes a compelling read for anyone, including adults. It includes a glossary and timeline. Most importantly, it explains the problem that had endured for centuries – that of solving timekeeping at sea.
For hundreds of years, ship voyages were harrowing adventures. Ocean travel had opened up the world to adventure and trade, but hundreds of ships had gone down at sea by the beginning of the 1700s. One of the major reasons for these disasters was the fact that there was no way to perfect the determination of longitude, or east-west location at sea.
Since ancient times, accurate latitude (or north-south location) had been found pretty easily by using the North Star or the sun as a starting point. Longitude, on the other hand, required an experienced navigator who would spend hours in the day calculating a position that was at best, an estimate. At worst, it was in error and ended in disaster.
In October 1707, the British Navy suffered an unthinkable loss when six ships hit the shoals off the Isles of Scilly (28 miles off the coast of Cornwall, England). Four of the ships went down and over 1700 sailors were lost. In 1714, the British Parliament made an unusual decision. They promised a prize – the Longitude Prize – to anyone who could come up with an accurate way to determine longitude at sea. The prize was worth 20,000 pounds – a fortune and equal to several million dollars today. Of course, this was a paltry sum compared to the lives – and fortunes – being lost at sea.
After reading Dash’s young adult version, I realized that Dava Sobel had written the adult version of this amazing story in “Longitude: the True Story of a Lone Genius Who Solved the Greatest Scientific Problem of His Time” (1995).
Dava Sobel had long been interested in science – it began in childhood with Galileo, maps, geography and measurement of the earth. After becoming a writer, her scientific curiosities led her to attend The Longitude Symposium at Harvard in 1993 headed by William J. H. Andrewes. (The symposium was organized at Harvard in connection with the 14th Annual Seminar of the National Association of Watch and Clock Collectors.” The papers presented at the 3-day event are published in “The Quest for Longitude” (1996). Scholars from around the world described the problem of longitude in the centuries before the 19th and the struggles of William Harrison to not only make a clock capable of keeping time at sea, but of his struggle to convince the Board of Longitude to award him the prize in 1765 after four decades of work. In the end, Harrison’s mechanical timekeeper, known today as the chronometer, kept perfect time at sea.
“The Quest for Longitude” includes the entire story with lavish illustrations but it can be a heady work with many long and scholarly lectures. Dava Sobel encapsulated the story perfectly in “Longitude.” In 1998, Andrewes and Sobel collaborated and published “The Illustrated Longitude” complete with Sobel’s prose and illustrations from Andrewes studies.
Two wonderful video recordings are based on Sobel’s book. “Longitude," produced by A&E for television in 1999, stars Jeremy Irons and Michael Gambon. This version combines the stories of John Harrison's forty-year obsession with building his perfect timekeeper and naval officer Rupert Gould. In 1976, Gould discovered Harrison's chronometers that had been neglected for many years. He devoted himself to restoring the masterpieces. The second production is “Lost at Sea: the Search for Longitude” (1998). It was produced by NOVA and is narrated by Richard Dreyfuss. Both video recordings include short interviews or introductions with Dava Sobel.
Two books for children explain the quest for longitude and the invention of John Harrison. Katherine Lasky and Kevin Hawkes teamed up on a beautifully written and illustrated picture book, “The Man Who Made Time Travel” in 2003. Louise Borden wrote the poetic (and sometimes too wordy) “Sea Clocks: The Story of Longitude” (2004) illustrated by Erik Blegvad.
Whatever your interest or preference for learning, I urge you to read or watch any of the accounts of John Harrison’s inventions and the world’s quest for longitude. They are all in the Minuteman Library catalog and librarians at the Morrill Memorial Library can help you find the version you prefer.