American astronomer, naval officer, oceanographer and author Matthew Fontaine Maury, who first served the United States Navy and then the Confederacy States Navy, made significant contributions in oceanography. His book Physical Geography of the Sea is counted among the first comprehensive books on oceanography. Navies and merchant marines across the world adopted his uniform system of recording oceanographic data.
James Rennell was an English historian and geographer. A pioneer of oceanography, Rennell is often referred to as the Father of Oceanography. Rennell, who served as a Surveyor General of Bengal, India, is credited with producing some of the earliest accurate maps of Bengal. James Rennell is also credited with co-founding the Royal Geographical Society in London in 1830.
13 John Murray
Born to Scottish migrants in Canada, John Murray later went back to Scotland to study medicine but quit without graduating. He later studied geology and became one of the pioneers of oceanography. He was also associated with the Challenger Expedition and was knighted for his work as a marine biologist.