Prologue: The History of Oceanography Prologue: Quick Review Questions P.1 The Early Times 1. Subfields of oceanography include geological oceanography (or marine geology), physical oceanography (including marine meteorology), chemical oceanography (or marine chemistry), biological oceanography (or marine biology), and ocean engineering. 2. Early sailors often piloted their way from one landmark to another, traveling along the shore and beaching their boats each night. Later, sailors on extensive open ocean voyages used careful observation and documentation of where prominent stars rise and set on the horizon. 3. The Polynesians used a star compass, divided into thirty-two segments, based on where prominent stars and constellations rise and set on the horizon. This formed the basis for documenting the direction of travel of prominent wave swells. 4. Earth's circumference was first calculated by the Greek geographer Eratosthenes (c.276-195 B.C.) by calculating differences in the angle of the Sun's rays on the surface of Earth with respect to a perpendicular. 5. Ptolemy's atlas improved understanding of world geography by establishing world boundaries for the known continents and oceans, including more than 8000 places listed by latitude and longitude. It produced some confusion later in time because it was based on a value for Earth's circumference of only 29,000 km (18,000 mi), much smaller than the actual value of roughly 40,000 km (25,000 mi). P.2 The Middle Ages 1. Longer ocean voyages were possible during the Middle Ages because of improvements in ship building. 2. During the 10th century the North Atlantic was explored by the Vikings, Arab and Chinese sailors exp