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?"