Base

The Borden Base Line is a 39,009.73 feet (7.42 miles ) survey line through the State of Massachusetts. The line was the first project of its kind undertaken in America and its establishment was the key element for Massachusetts pioneering mandate to survey the entire state. 

The challenge was to use trigonometrical principles, instead of astronomical observation alone, to provide greater accuracy in surveying large areas.

Established in 1935 as the Valparaiso Bombing and Gunnery Base, the base supported the U.S. Army Air Corps, the predecessor to the U.S. Air Force, as its primary facility for training new pilots in bombing and gunnery tactics. It also served as a test facility for aircraft, aircraft armament, air-delivered munitions and other aircraft systems. The base was renamed Eglin Field in 1937 in honor of Air Corps aviator Lt. Col. Frederick I. Eglin, who trained pilots during World War I, and who had recently died in an aircraft accident. After Congress created the U.S.