Join the Map Men as they tackle the difficult problem of finding longitude. (up / down)
Sailors had long needed an accurate method of determining longitude. Sadly, the practice of dead reckoning sometimes proved true.
For more information, see:
“Longitude: the true story of a lone genius who solved the greatest scientific problem of his time” by Dava Sobel
“Harrison decoded: towards a perfect pendulum clock” edited by Rory McVoy & Jonathan Betts