Satellites
EARLY SAILING SHIPS
Humans for centuries have been drawn to the sea by its
magnificent power and daunting mystery. With little or no knowledge of the
puzzling currents, eddies, circulation patterns, and seasonal changes, many
early ocean voyagers found themselves at the mercy of the sea. Still, this
did not stop the westward movement across the sea to the New World and beyond.
Benjamin Franklin, Deputy Postmaster General for the American colonies, became
curious about the length of time it took ships traveling from Falmouth, England,
to reach New York compared to the time it took them to reach Rhode Island
when traveling from London, England. The London-Rhode Island route was longer
distance-wise, but took two weeks less travel time. He sought answers from
experienced seamen like his cousin, Nantucket Sea Captain Timothy Folger.
Folger who was familiar with whaling told of a powerful stream in the sea
that flowed from the Florida Gulf and up the New England coastline. Even the
whales avoided this stream and chose to swim at its outer edges. Whaling ships
occasionally met with British ships stuck in the current trying to sail against
it. The Falmouth (British) sea captains refused the advice of the American
seamen/fishermen who had advised them to avoid the stream or to cross it and
get out of it as opposed to "stemming" (sailing against) it.
Franklin's interest in the current never waned (faded). While sailing across
the Atlantic Ocean from London to Philadelphia in 1775, Franklin made his
first scientific examination of the current. During the voyage, he kept a
log of the temperature readings around the Gulf Stream. He later combined
this with Captain Folger's knowledge of the current to produce a chart of
the Gulf Stream and its surroundings as a navigational aid.
Alexander Dallas Bache (1806-1867) was the great-grandson of Benjamin Franklin.
In 1843 he became the second superintendent of the U. S. Coast Survey. Following
in his great-grandfather's footsteps, he focused the efforts of the Survey
on the Gulf Stream. Survey ships, using devices and techniques developed by
scientists and sailors over the past century, crisscrossed the Gulf Stream
taking soundings, bottom samplings and temperature, speed and direction measurements
of the current itself. The Survey became the first governmental agency to
undertake a sustained oceanographic study of the Gulf Stream.
If you're a real history buff and you'd like to know more about early seafarers,
check out CARRY ON, MR. BOWDITCH (listed in our Book
Galley) by J. L. Latham.
Questions that come to mind:
1. What are the advantages of studying the oceans from space (via satellite)?
2. Why are traditional methods (current meters, buoys, water sampling bottles, tide gauges, etc.) of studying the ocean still crucial (necessary)?
3. What significant contribution did Benjamin Franklin make to ocean navigation?
4. What is a "global positioning system?"
To find out the answers to these and other questions you may have, check out our "Helpful Links"!
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