Mapping the Gulf Stream
Cousin Timothy Folger and Uncle Ben Franklin are credited with the publication of the first map of the Gulf Stream. Cousin Timothy Folger, was a Nantucket Merchant ship captain. Franklin was the Postmaster general. Folger was up to speed on transit times that were a fortnight longer sailing to the colonies than the return trip to London. By the way, a fortnight is 14 days. At sea, the Gulf Stream is easy to spots as its waters are an emerald blue-green.
Two copies of the Franklin-Folger 1770 map were discovered in 1980 at the Bibliotheque Nationale in Paris. Franklin and Folger used a navigation chart of the Atlantic Ocean as their base map and added to it the course, the breadth and strength the Gulf Stream.
Franklin-Folger’s map, however, was not the first map of ocean circulation showing the Gulf Stream, Franklin-Folger are pre-dated by A. Kircher (1665) and by Happelius (1685). LINK
R. M. Farquhar and I. R. Fletcher
Science, VOL.207, 8 February 1980
Personal communion with Professor Stan Ulanski of
James Madison University