Atlantic Ocean as the mid-19th century. During the Age of Discovery, the Atlantic was also known to English cartographers as the Great Western Ocean. The International Hydrographic Organization (IHO) defined the limits of the oceans and seas in 1953, but some of these definitions have been revised since then and some are not used by various authorities, institutions, and countries, see for example the CIA World Factbook. Correspondingly, the extent and number of oceans and seas varies. The Atlantic Ocean is bounded on the west by North and South America. It connects to the Arctic Ocean through the Denmark Strait, Greenland Sea,
Milky seas effect Verne's "Twenty Thousand Leagues Under the Sea"). In fact, the effect has not been rigorously documented nor thoroughly explained, even in modern times. Between 1915 and 1993, 235 sightings of milky seas were documented, most of which are concentrated in the northwestern Indian Ocean and near Indonesia. The luminescent glow is concentrated on the surface of the ocean and does not mix evenly throughout the water column. In 1985, a research vessel in the Arabian Sea took water samples during milky seas. Their conclusions were that the effect was caused by the bacteria "Vibrio harveyi". Mareel is typically caused by