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Fourth Principal Extended Meridian
Encyclopedia
The Fourth Principal Extended Meridian continues the Fourth Principal Meridian
through Wisconsin
and northeastern Minnesota
, and, with the south boundary of Wisconsin as its base line, governs all the surveys in the former and those in the latter state lying east of the Mississippi River
, and the third guide meridian west (of the fifth principal meridian system), north of the river.
Fourth Principal Meridian
The Fourth Principal Meridian, set in 1815, is the principal meridian for land surveys in northwestern Illinois and west-central Illinois, and its 1831 extension is the principal meridian for land surveys in Wisconsin and northeastern Minnesota...
through Wisconsin
Wisconsin
Wisconsin is a U.S. state located in the north-central United States and is part of the Midwest. It is bordered by Minnesota to the west, Iowa to the southwest, Illinois to the south, Lake Michigan to the east, Michigan to the northeast, and Lake Superior to the north. Wisconsin's capital is...
and northeastern Minnesota
Minnesota
Minnesota is a U.S. state located in the Midwestern United States. The twelfth largest state of the U.S., it is the twenty-first most populous, with 5.3 million residents. Minnesota was carved out of the eastern half of the Minnesota Territory and admitted to the Union as the thirty-second state...
, and, with the south boundary of Wisconsin as its base line, governs all the surveys in the former and those in the latter state lying east of the Mississippi River
Mississippi River
The Mississippi River is the largest river system in North America. Flowing entirely in the United States, this river rises in western Minnesota and meanders slowly southwards for to the Mississippi River Delta at the Gulf of Mexico. With its many tributaries, the Mississippi's watershed drains...
, and the third guide meridian west (of the fifth principal meridian system), north of the river.