Benjamin Franklin and the Gulf Stream

At this point in our story, I have some bad news: Benjamin Franklin did not discover the Gulf Stream. In the early 1500s, shortly after Columbus acquainted the European world with the existence of American,  Ponce de Leon spent a good deal of time off the coast of Florida in search of the Fountain of Youth. While he never found the Fountain, he did "discover" Florida and he did take notice of the Florida Current and probably the Gulf Stream.

Now any south Florida schoolboy or schoolgirl knows that if you stand on the beach and look out towards the horizon, you can see what looks like the ripples of a river chugging along headed north about a mile or so offshore (at least in Palm Beach, where the Gulf Stream makes its closest approach to land). So the fact that Ponce noticed, an accomplished sailor, isn't much of a discovery, but hey, at least he noticed.

Was he the first? Truth be told, the Seminole Indians, who lived in Florida long before any European arrived, probably were aware of the Gulf Stream. They probably even had a name for it. If I get a chance, I plan to look into it.

What Ben Franklin did do was help publish one of the early maps of the Gulf Stream and he also spent a good deal of time making temperature measurements of the Gulf Stream. For that, he deserves some credit but I think this is another case where the legend exceeds the man.

The following account comes from NASA:

franklin_cut_sm3.gif (29779 bytes)From 10 August 1753 through 31 January 1774, Benjamin Franklin held the post of deputy postmaster general of North America (Van Doren, 1938). During this time, the American postal ships could make the journey from England to the colonies days, if not weeks, faster than the English merchant ships. The English postal authorities were so amazed that they wrote to Franklin for possible reasons (Cohn, 1998; Richardson, 1980). Franklin consulted his cousin, Timothy Folger, a whaling ship captain from Nantucket, for an answer. Captain Folger told Franklin about the Gulf Stream and created a chart (similar to the one shown below) illustrating its affect on ships (Van Doren). In fact, at this time, most of the American and Spanish ship captains were well aware of the Gulf Stream. They knew to sail in the Gulf Stream while travelling to England and to stay out of it when returning to the colonies. Franklin had Folger's chart printed and presented this information to the British postal authorities. Unfortunately, this new information was ignored by the British (Cohn; Richardson).

Franklin, however, became intrigued by the idea of a "stream" existing in a large body of water such as the Atlantic ocean. Therefore, in 1775 during his return voyage from England to the colonies, Franklin took temperature measurements of the ocean water from two to four times per day (Van Doren). He knew that these measurements would mark the location of the Gulf Stream, because the Gulf Stream carries warm water from the south to the north. Therefore, the Gulf Stream is warmer than the surrounding waters.

In 1776, the American Congress appointed three commissioners to travel to France in order to gain French support in the American Revolution. Franklin was, of course, chosen as one of the commissioners. On 26 October, Franklin left Philadelphia on board the Reprisal. "The indomitable old man, who was almost certain to be hanged for high treason if the Reprisal should be captured, noted the temperature of air and water every day, again studying the Gulf Stream" (Van Doren).

Franklin did not return to America until 1785. On this trip, he again took daily measurements of the water temperature and notes concerning the currents, water color and gulf weed content. He also wrote Maritime Observations on this trip. This work included his notes on the Gulf Stream's causes and uses as well as a multitude of other information about sailing the oceans. (Van Doren). [Oceanography History: Ben Franklin and the Gulf Stream]

So the truth of the matter is that Timothy Folger, the Nantucket whaler, drew the map and Franklin embellished it and published it. Who gets credit? Franklin, mostly, although recent historical accounts now mention Folger's name along with Franklin's. The better part of Franklin's contribution, in my opinion, is the work that Franklin did subsequent to Folger's map. On at least two voyages across the Atlantic, Franklin played oceanographer and published those findings in a set of notes called Maritime Observations. As soon as I get hold of those notes, I'll fill in a few more details here.

Enough of the legends. Let's get down to the interesting part of the story, the part between Ponce de Leon's first observations and Folger's map.

Midshipman Pamela Phillips, of the U.S. Naval Academy (unless she has graduated) and Richard Gasparovic, with the Applied Physics Laboratory of John Hopkins University, have created the most informative and detailed history of the Gulf Stream that I have ever seen. (I admit, though, I haven't looked exhaustively.) On their web site, they supply a very nice series of timelines of this history that I've taken the liberty to duplicate below. Their web site also provides an excellent summary of the general characteristics of the Gulf Stream and though we will study this topic in greater detail later, it wouldn't be a bad idea to check it out and take a peek.

Here, in a series of four figures, are their timelines:

 1500GulfStream.gif (6782 bytes)
1600GulfStream.gif (7412 bytes)
1700GulfStream.gif (12155 bytes)
1900GulfStream.gif (35162 bytes)
Timeline of the Gulf Stream copied without permission from Midshipman Pamela Phillips, of the U.S. Naval Academy (unless she has graduated) and Richard Gasparovic, with the Applied Physics Laboratory of John Hopkins University, who didn't leave their e-mail address on their site. If you see this and know them, please drop me a line. I would like to ask their permission to use it as an educational reference. [For more, go to]

Isn't that a wonderful way to read history? I thought so and that's why I wanted to bring it to you here. One quick note: there seems to be a disparity between the account of Folger's map and Franklin's date of publication of the map. I'll check it out.

There is also one thing missing on this map, an event that occurred near my home town in Florida when I was a young man. Again, I'm afraid my research on this subject isn't quite up to snuff but bear with me. Sometime in the late 60s (as memory serves me), my parents took me to the docks at Riviera Beach Florida (right next to the Florida Power and Light Electrical Station smokestacks) to see the launch of a submersible called (you guessed it) the Ben Franklin. I remember being there that day and I remember they were having some kind of a problem because it took a while longer than it was supposed to (and I was an impatient kid). But they finally got it on board a ship and headed out towards the Gulf Stream where they drifted for several days and taking data and making observations. For me it was just fascinating, like a space voyage. At that time I had already made up my mind that I was going to be an oceanographer and seeing these aquanauts ready their vessel and launch out to see was a trip!

What they found and how far they went, I don't recall and haven't been able to find any reference material on this voyage, but I will. The point is that you never know how something will affect your life and that you should take advantage of any opportunity to pursue your dreams while it exists. Because my parents were kind enough to take me to see this incredible vessel, I can now give you my personal insights into the history of research on the Gulf Stream.

And that is the end of that story, for now.

Ben Franklin: An Enlightened American

Ben Franklin: A Documentary History

Ben Franklin Institute of Global Education

Benjamin Franklin: Glimpses of the man

Quotes and sayings by Ben Franklin

Oceanography History: Ben Franklin and the Gulf Stream 1785

Gulf Stream Journal and Publication Reference from Midshipman Phillip's site:
The Gulf Stream

1. Pillsbury, John Elliott, "The Gulf Stream, Methods of the Investigation and Results of the Research," Appendix No. 10, Report for 1890, United States Coast and Geodetic Survey, Washington, Government Printing Office, 1981.

2. MacLeish, William H., The Gulf Stream, Houghton Mifflin Co., Boston, 1989.

3. De Vorsey, Louis, "Pioneer Charting of the Gulf Stream: The Contributions of Benjamin Franklin and Wiliam Gerard De Brahm," Imago Mundi, vol. 28, pp. 105-120 (1976).

4. Schlee, Susan, The Edge of an Unfamiliar World - A History of Oceanography, E. P. Dutton & Co., Inc.,New York, 1973.

5. Wilkerson, J. C., M. Bratnick, and G. L. Athey, "Aircraft Observations of a Cyclonic Eddy South of the Gulf Stream," Naval Oceanographic Office Report IR No. 69-41, April 1969.

6. Wilkerson, J. C., "Positioning the Gulf Stream with Airborne Radiation Thermometer Data," Naval Oceanographic Office Report IR No. 68-33, May 1968.

7. Gaskell, T. F., The Gulf Stream, Cassell &Co. Ltd., 1972.

8. Porter, D. L., A. R. Robinson, S. M. Glenn, and E. B. Dobson, "The Synthetic Geoid and the Estimation of Mesoscale Absolute Topography from Altimeter Data," Johns Hopkins APL Technical Digest, vol. 10, pp. 369-379 (1989).

9. Warren, Bruce A., and Carl Wunsch (eds.), Evolution of Physicsl Oceanography, MIT Press, Cambridge, MA, 1981.

10. Stommel, Henry, The Gulf Stream, University of California Press, second edition, 1966.

11. Richardson, Philip L., "Benjamin Franklin and Timothy Folger's First Printed Chart of the Gulf Stream," Science, vol. 207, pp. 643-645 (1980).