The Benjamin Franklin Tercentenary

A Chart of the Gulf Stream, 1786.

This afternoon we took up several branches of gulf weed; but one of these branches had something peculiar in it…a small yellow berry filled with nothing but wind; besides which it bore a fruit of the animal kind, very surprising to see. It was a small shell-fish like a heart.

—Benjamin Franklin,
Journal of a Voyage, 1726

Never one to waste an opportunity or to pass the time unoccupied, Franklin used his multiple transatlantic journeys—which lasted weeks in each direction—to observe and study the natural phenomena around him. Franklin carefully recorded his observations, keeping journals filled with details documenting the origins of storms, the formation of lightning, and the effects of oil on water. His fascination with maritime weather led him to include meteorological information in his Poor Richard’s Almanack, helping both travelers and colonial farmers prepare for shifting weather patterns.

Franklin also studied the transatlantic path of the Gulf Stream, charting its route with his cousin Timothy Folger, a Nantucket whaling captain. Their surprisingly accurate map has been widely used by seamen of many nations, reducing the lengthy ocean crossing and spurring interest in the mysteries of the Atlantic.

Having since crossed this stream several times in passing between America and Europe, I… know when one is in it; and besides the gulph weed with which it is interspersed, I find that it is always warmer than the sea on each side of it, and that it does not sparkle in the night.

—Benjamin Franklin,
“Maritime Observations,” Transactions
of the American Philosophical Society, 1786

On his transatlantic voyages, Franklin noted changes in water temperature and atmospheric conditions and the presence of whales feeding on plankton in the warm water. He also noticed that similar ships taking different routes across the Atlantic made the crossing at different speeds—and that the shortest course was not necessarily the fastest. This all made sense when his cousin Timothy Folger, a Nantucket sea captain, told him about the Gulf Stream and drew its location on a chart of the Atlantic. The Franklin/Folger chart of the Gulf Stream was amazingly accurate.

“Maritime Observations,” 1786

When I was a boy, I amused myself one day with flying a paper kite while I was swimming

Franklin’s flair for technical ingenuity combined with his youthful love for swimming to produce “a method in which a swimmer may pass to great distances with much facility, by means of a sail.” Predating windsurfing by centuries, Franklin discovered he could harness the power of the wind with his kite and be pulled effortlessly across a mile-wide pond.