Ptolemy 's 2nd-century '' Geography '' used the same prime meridian but measured latitude from the Equator instead . After their work was translated into Arabic in the 9th century , Al-Khwārizmī 's '' Book of the Description of the Earth '' corrected Marinus ' and Ptolemy 's errors regarding the length of the Mediterranean Sea , causing medieval Arabic cartography to use a prime meridian around 10 ° east of Ptolemy 's line . Mathematical cartography resumed in Europe following Maximus Planudes ' recovery of Ptolemy 's text a little before 1300 ; the text was translated into Latin at Florence by Jacobus Angelus around 1407 . In 1884 , the United States hosted the International Meridian Conference , attended by representatives from twenty-five nations . Twenty-two of them agreed to adopt the longitude of the Royal Observatory in Greenwich , England as the zero-reference line . The Dominican Republic voted against the motion , while France and Brazil abstained . France adopted Greenwich Mean Time in place of local determinations by the Paris Observatory in 1911
International Meridian Conference
International Meridian Conference
Geographic coordinate system