The Benjamin Franklin and Timothy Folger Charts of the Gulf Stream

Abstract

In September 1978 I found two prints of the first Franklin-Folger chart of the Gulf Stream in the Bibliothèque Nationale in Paris. Although this chart had been mentioned by Franklin in 1786, all copies of it have been “lost” until now.1 The Franklin-Folger chart was not only excellent for its time,2 but it remains today a good summary of the general characteristics of the Gulf Stream. Because of its historical role in our understanding of the Stream and in the development of oceanography, I would like to discuss its depiction of the Gulf Stream relative to later charts and recent measurements.