Ben Franklin and the Gulf Stream

The warm Gulf Stream current that flows eastward across the North Atlantic Ocean is one of the greatest movements of water on Earth. It is driven east by prevailing westerly winds, and is part of a great loop that then recrosses the Atlantic to the Caribbean. The current had been known since 1513, when Spanish explorer Juan Ponce de León found his ship moving back north off Florida despite winds blowing him south. But it was only properly charted in 1770, by US statesman and scientist Benjamin Franklin.

As deputy postmaster of the British American colonies, Franklin was fascinated by why it took British packet ships delivering mail two weeks longer to cross the Atlantic than American merchant ships. Already famous for his invention of the lightning conductor, he asked Nantucket whaling captain Timothy Folger why this might be.

Franklin’s chart was published in 1770 in Britain, but it would be years before British captains learned to use the Gulf Stream to cut sailing times.

Source: The Science Book: Big Ideas Simply Explained (2014) by DK Publishing.