Re-order Paragraphs

Put the sentences in the correct order:

1. ▲▼His invention kept reliable time at sea, finally allowing navigators to pinpoint their position with confidence.
2. ▲▼In the 1760s, a self-taught carpenter named John Harrison solved this by building a compact, spring-driven timepiece.
3. ▲▼Early pendulum clocks, however, lost all accuracy on a rolling, swaying ship.
4. ▲▼The problem was that calculating longitude required knowing the exact time at a fixed reference point back home.
5. ▲▼For centuries, sailors crossing the open ocean struggled to determine how far east or west they had travelled.