A warm ocean current flowing north from the Gulf of Mexico, along the east coast of the U.S., to the southeast coast of Newfoundland, where it forms the western edge of the North Atlantic Current. Benjamin Franklin published the first map showing the location of the Gulf Stream in 1770. The current can either help or hinder a ship by 70 miles per day, depending on the direction of travel. Franklin announced his findings in a letter to a French scientist in 1785. He noted that one can tell if a ship is in it by measuring the water temperature; the Gulf Stream is much warmer than the ocean water on either side of it.