In the age of the iPhone, even with iOS6 maps, it’s hard to imagine how difficult global positioning and timekeeping used to be. I recently learned the story of John Harrison, one of the many brilliant men who paved the way to portability. In the 18th century, the height of the sun was used to measure north and south, but only the correct time could tell sailors east from west. Unfortunately, time zones made time a relative concept. In fogs, drifting blind into neighboring time zones caused navigation errors, shipwrecks and the loss of thousands of lives. In 1714 the British Government offered £20,000 to the person or persons who could solve the problem of time zones, which caused sailors to lose track of east and west and had cost thousands of lives. The scientists of the day suggested celestial navigation methods that were impossible from a moving ship in changeable weather conditions. Their methods required observatories and controlled conditions which nautical coves could not enjoy...