Benjamin Franklin, Mapmaker: Who First Charted the Gulf Stream

The first person to put the Gulf Stream on a chart was not a navigator or an oceanographer but a statesman: Benjamin Franklin. The current had been known since Ponce de Leon observed it in 1513, yet it went uncharted until Franklin mapped it.

Benjamin Franklin's map of the Gulf Stream. Credit: NOAA.

A statesman's contribution to science

Alexander Agassiz, one of the leading oceanographers of the 19th century, credited Franklin with giving the exploration of the Gulf Stream its first scientific basis. Franklin published his map of this river in the ocean in 1769. Two hundred years later, a submersible named after him drifted beneath the surface to study the same current.

The Coast Survey takes a closer look

In 1843 the United States Coast Survey — the earliest ancestor of NOAA — set out to study the Gulf Stream in far more detail than a map of its path could give. Its surveyors wanted to know:

• how deep the water was
• how warm it was at different depths
• what the ocean bottom was like
• which way the currents ran at different depths, and how fast
• how much plant and animal life it held

Those early observations turned up features no surface chart could show, among them bands of cool and warm water and the "Charleston Bump."

Sources

Based on "Who first charted the Gulf Stream?" from NOAA's National Ocean Service, a work of the United States government in the public domain.