Question: When was the American explorer which Andrew Ellicott  served as a teacher in survey methods for born 

Context paragraphs:
Cape Byrd: Cape Byrd ( ) is a low, ice-covered cape forming the northwest extremity of Charcot Island.  It was first seen from the air and roughly mapped by Sir Hubert Wilkins on December 29, 1929, in a flight from the "William Scoresby".  It was named by Wilkins for R. Admiral Richard E. Byrd, U.S. Navy, noted American explorer and leader of five expeditions to Antarctica.  It was remapped from air photos taken by U.S. Navy Operation Highjump in 1947 by Derek J.H. Searle of the Falkland Islands Dependencies Survey in 1960.

Ellicott's Stone: Ellicott’s Stone, also known as the Ellicott Stone, is a boundary marker in northern Mobile County, Alabama.  It was placed on April 10, 1799 by a joint U.S.-Spanish survey party headed by Andrew Ellicott.  It was added to the National Register of Historic Places on 11 April 1973.

Meriwether Lewis: Meriwether Lewis (August 18, 1774 – October 11, 1809) was an American explorer, soldier, politician, and public administrator, best known for his role as the leader of the Lewis and Clark Expedition, also known as the Corps of Discovery, with William Clark.

Ellicott's Rock: In 1811, Andrew Ellicott made a survey for the state of Georgia to resolve the boundary dispute between Georgia and North Carolina, which in 1810 had resulted in a short armed conflict between the two called the Walton War.  He engraved a large rock in the Chattooga River with "N-G", standing for North Carolina - Georgia.  The location had been prescribed in part in 1787 by the Treaty of Beaufort, though the river was not named explicitly, but rather as a then-undiscovered tributary of the Savannah River between Georgia and South Carolina.  The nominal latitude of 35°N was later specified by the U.S. Congress.

Benjamin Banneker: Benjamin Banneker (November 9, 1731October 9, 1806) was a free African American almanac author, surveyor, naturalist, and farmer.  Born in Baltimore County, Maryland, to a free African American woman and a former slave, Banneker had little formal education and was largely self-taught.  He is known for being part of a group led by Major Andrew Ellicott that surveyed the borders of the original District of Columbia, the federal capital district of the United States.

Cape Ellsworth: Cape Ellsworth ( ) is a sheer rock bluff 290 m high forming the north end of Young Island in the Balleny Islands.  It was named by personnel of the "Discovery II" in 1936 for American explorer Lincoln Ellsworth.  The vessel, after picking up Ellsworth at Little America on the Ross Ice Shelf, made a running survey around the northern end of the Balleny Islands on the way back to Australia.

A. E. Douglass: A. E. (Andrew Ellicott) Douglass (July 5, 1867 in Windsor, Vermont – March 20, 1962 in Tucson, Arizona) was an American astronomer.  He discovered a correlation between tree rings and the sunspot cycle, and founded the discipline of dendrochronology, which is a method of dating wood by analyzing the growth ring pattern.  He started his discoveries in this field in 1894 when he was working at the Lowell Observatory.  During this time he was an assistant to Percival Lowell, but fell out with him when his experiments made him doubt the existence of artificial "canals" on Mars and visible cusps on Venus.

James Robertson (explorer): James Robertson (June 28, 1742 – September 1, 1814) was an American explorer, soldier and Indian agent, and one of the founding fathers of the State of Tennessee.  An early companion of explorer Daniel Boone, Robertson helped establish the Watauga Association in the early 1770s, and helped defend Fort Watauga from an attack by the Cherokees in 1776.  In 1779, he cofounded what is now Nashville, and was instrumental in the settlement of Middle Tennessee.  He served as a brigadier general in the Southwest Territory militia in the early 1790s.

Mythology and legacy of Benjamin Banneker: A substantial mythology exaggerating Benjamin Banneker's accomplishments has developed during the two centuries that have elapsed since he lived.  Several such urban legends describe Banneker's alleged activities in the Washington, D.C. area around the time that he assisted Andrew Ellicott in the federal district boundary survey.  Others involve his clock, his almanacs and his journals.  All lack support by historical evidence.  Some are contradicted by such evidence.

Andrew Ellicott: Andrew Ellicott (January 24, 1754 – August 28, 1820) was a U.S. surveyor who helped map many of the territories west of the Appalachians, surveyed the boundaries of the District of Columbia, continued and completed Pierre (Peter) Charles L'Enfant's work on the plan for Washington, D.C., and served as a teacher in survey methods for Meriwether Lewis.

Supporting paragraphs: Andrew Ellicott Meriwether Lewis
Answer: August 18, 1774