Darién Expedition of 1854 (as he also did with William Lewis Herndon's exploration of the Valley of the Amazon ) to the Secretary of the Navy. His nephew, s:Darien Exploring Expedition (1854) Lieutenant John Minor Maury USN, (not to be confused with Lieutenant John Minor Maury USN, M. F. Maury's _brother_ who died of malaria while in the U. S. Navy) had been working at the Naval Observatory with his uncle Matthew and was well prepared with both knowledge and equipment. Lieutenant Maury was appointed by Strain as the expedition's 1st assistant-engineer, as well as assistant-astronomer and secretary. Lieutenant Strain later worked on another project for Commander M F Maury, taking depth soundings of the ocean floor of the Atlantic Ocean that were compiled into sea-floor charts. The U.S. Naval Observatory was also known as the National Observatory. Both terms were used for ten years until an order was finally passed down to use Naval Observatory. This is why many old writings of that time use "National Observatory", the original name given when President John Quincy Adams signed the bill for its creation. Middle name (Grier) source: The New York Times Jan.7, 1859 References s:Darien Exploring Expedition (1854) United States Navy Darien Exploring Expedition of the Isthmus of Panama 1854. https://en.wikisource.org/wiki/Darien_Exploring_Expedition_(1854) Balf, Todd; The Darkest Jungle: The True Story of The Darien Expedition and America's Ill-Fated Race to Connect The Seas, 2003, Crown Publishers, New York, . Crosby, Hon. Nathan; Annual Obituary Notices of Eminent Persons who Have Died in the United States Navy, for 1857, Boston: Phillips, Sampson & Company, 1858, Appendix to v. [1] (p.[408]-432) includes obituary notices for the years 1851 to 1857. Strain, Isaac G.; Cordillera and Pampa, Mountain and Plain: Sketches of a Journey in Chili and The Argentine Provinces in 1849, New York: Horace H. Moore, 1853; Lightning Source, Inc., 2007, ; . 1821 births 1857 deaths American explorers United States Navy officers