Before Google Maps sent personalized routes to our phones, people used actual maps to get around. Although those paper documents were fine for traversing continents with notable physical features and landmarks, they weren’t nearly as effective for crossing vast, featureless oceans, especially when navigators had to keep piloting the ship after dark. Sure, a compass could tell you where you were going, but if you lost track of your location, your ship could be lost at sea forever. The risk was so great that in 1714, the British government created the Longitude Act, which offered a reward for anyone who could find a way to determine longitude at sea. In response, tinkerers, clockmakers, astronomers, and naval officers all scrambled to complete the “quest for longitude.” Now, an exhibit at the Folger Shakespeare Library, created by the staff at Greenwich, England’s National Maritime Museum, presents the different solutions they came up with through more than five decades of study and experimentation. Among the exhibited items are clockmaker John Harrison’s H4 marine timekeeper, astronomical tables developed by Nevil Maskelyne, and paintings from Captain James Cook’s Pacific voyages. A working compass is not required to navigate these displays. The exhibition is on view Mondays through Saturdays 10 a.m. to 5 p.m. and Sundays noon to 5 p.m. at the Folger Shakespeare Library, 201 East Capitol St. SE. Free. (202) 544-4600.