Marinus of Tyre
Biography and historical context 
Originally from Tyre in the Roman province of Syria. He and his work were a precursor to that of the great Greek geographer Claudius Ptolemy (90 - 168 AD), who used Marinus' work as a source for his Geographia, and acknowledges his great obligations to him. Later, Marinos is also cited by the Arab geographer al-Masudi. Beyond this little is known of his life.
Contribution to geography 
Marinus' geographical treatise is lost and known only from Ptolemy's critical remarks. He introduced improvements to the construction of maps and developed a system of nautical charts. His chief legacy is that he first assigned to each place a proper latitude and longitude; he used a "Meridian of the Isles of the Blessed (Canary Islands or Cape Verde Islands)" as zero meridian, and the parallel of Rhodes for measurements of latitude. Ptolemy mentions several revisions of Marinus' geographical work, which is often dated to AD 114, though he may have been a near-contemporary of Ptolemy. Marinus estimated a length of 180,000 stadia for the equator, corresponding to a circumference of the Earth of 33,300 km, about 17% less than the actual value. (Both numbers depend upon the length assigned to the Greek stade).
He also carefully studied the works of his predecessors and the diaries of travellers. His maps were the first in the Roman Empire to show China. He also invented the equirectangular projection, which is still used in map creation today. A few of Marinus' opinions are reported by Ptolemy. Marinus was of the opinion that the Okeanos was separated into an eastern and a western part by the continents (Europe, Asia and Africa). He thought that the inhabited world stretched in latitude from Thule (Shetland) to Agisymba (Tropic of Capricorn) and in longitude from the Isles of the Blessed to Shera (China). Marinus also coined the term Antarctic, referring to the opposite of the Arctic Circle.
See also 
- Hubert Cancik and Helmuth Schneider (ed.): "Marinus", Brill's New Pauly, Brill, 2010:
M. of Tyre (Μαρῖνος; Marînos), Greek geographer, 2nd cent. AD
- George Sarton (1936). "The Unity and Diversity of the Mediterranean World", Osiris 2, p. 406-463 .
- Chisholm 1911.
- Harley, J. B. (John Brian); Woodward, David. The History of cartography. Humana Press. pp. 178–. ISBN 978-0-226-31633-8. Retrieved 4 June 2010.
- A. Forbiger, Handbuch der alten Geographie, vol. i. (1842);
- E. H. Bunbury, Hist. of Ancient Geography (1879), ii. p. 519;
- E. H. Berger, Geschichte der wissenschaftlichen Erdkunde der Griechen (1903).