Dava Sobel’s Longitude: The True Story of a Lone Genius Who Solved the Greatest Scientific Problem of His Time, is, despite the lengthy title, a brief book laying out the story of John Harrison. Harrison, a clock-maker whose precision clocks made the calculation of longitude a much more precise science, was in a race for a royal grant to reward the discoverer of a method for giving precision to ships at sea. Harrison represented those who believed accurate clocks could solve the problem, while others argued that mapping the heavens would give sailors the best chance. Often we forget that loss of life greater than that on the Titanic could occur when ships ran aground, due to lack of knowledge concerning their longitude. Navigating the seas before GPS and before accurate watches, was often a matter of informed guessing with very high stakes. Harrison never did get to claim fully what he’d earned and we’ve all but forgotten how difficult finding the correct time was when our computers remind us, to the second, of precisely when we are.
Prior to science, the keeping of time was a religious function. Sacred calendars marked holidays—often with the ulterior motive of keeping farmers on track for when planting time for various crops, and their harvests, should commence. Telling the change of seasons by when to add or discard a layer of clothing seems eminently practical, but it doesn’t help an agricultural society to plan ahead adequately. The gods would give the time, and all they would require was a cut of the profits. It was, all things considered, a reasonable trade-off. And now holidays have mostly slipped their religious moorings to become times when we simply don’t have to go to work. Speaking of which—look at the time…